Dr Caroline Leaf and the chemistry of perceptions

Posted on November 16, 2014 by cedwardpitt

On her social media feed just now, Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist, said, “Your perceptions adjust your brain chemistry”.

Hmmm … yes and no.

I’m not really sure what Dr Leaf is trying to suggest with this statement, because it’s so vague. The brain works through the passage of an electrical current travelling along a nerve cell, and being passed to the next nerve cell by the release of a “chemical” neurotransmitter that floats across the space between the nerve cells. If that’s what Dr Leaf is referring when she talks about our brain chemistry, then sure, our perceptions adjust our brain chemistry. But then again, so does everything else that our brain does. In this sense, perception is nothing special.

What I think Dr Leaf was trying to suggest is that our mind influences our brain chemistry, following along with her “mind controls matter” theme. But perception is the process of translating the raw data into a signal that the brain can process, for example, the light coming into your eye is translated into the electrical impulses your brain can utilise. It’s not an explicit process. It has nothing to do with our consciousness or our volition.

Also, our “brain chemistry” as it’s considered in neuroscience is usually referring to the neurotransmitters and their function, which is often determined by our genetics and influences how we perceive and understand our environment [1].

So if anything, it’s not our perception altering our brain chemistry, but rather it’s our brain chemistry that alters our perceptions.

Our mind does not control our brain. Our brain is responsible for the function of our mind.

References

Caspi, A., et al., Genetic sensitivity to the environment: the case of the serotonin transporter gene and its implications for studying complex diseases and traits. Am J Psychiatry, 2010. 167(5): 509-27 doi: 10.1176/appi.ajp.2010.09101452

Dr Caroline Leaf and the tongues trivia tall tales

Posted on November 12, 2014 by cedwardpitt

In every day life, if someone started talking in strings of indecipherable, chaotic syllables, you’d be giving them quite a lot of space, concerned about how much methamphetamine they’d been using.

In the average charismatic church, it’s just another service (the speaking in tongues, not the meth).

I’ve grown up in Pentecostal churches, and was baptised in the Holy Spirit when I was a child, so I forget how freaky it is for those who’ve never seen a whole church start talking or singing in tongues. For the uninitiated, the Bible talks about speaking in other tongues, which is a “New Testament phenomena where a person speaks in a language that is unknown to him. This language is either the language of angels or other earthly languages (1 Cor. 13:1). It occurred in Acts 2 at Pentecost and also in the Corinthian church as is described in 1 Corinthians 14. This New Testament gift was given by the Holy Spirit to the Christian church and is for the purpose of the edification of the Body of Christ as well as for glorifying the Lord.” (http://carm.org/speaking-in-tongues)

In scientific terms, speaking in tongues is referred to as “Glossolalia”, from the Greek, ‘glosso-‘ ~ ‘the tongue’ and ‘-lalia’ ~ ‘to speak, to chat’. Scientists who initially studied it in the 60’s and 70’s drew the conclusion that glossolalia was related to psychopathology (that people who spoke in tongues were crazy) [1, 2], and in later decades, it was thought to be caused by a form of temporal lobe epilepsy [3].

Earlier today, Dr Caroline Leaf, a communication pathologist and self-titled cognitive neuroscientist, declared that, “When we speak in tongues, research shows that the areas involved in discernment in the brain increase in activity, which means we increase in wisdom.”

I was fascinated to find this research for myself. Dr Leaf never references her social media memes, so I started looking through the medical literature on the subject from respected databases like PubMed, and search engines like Google Scholar.

Despite a thorough search, I was only able to find one article that studied the pattern of brain activity during speaking in tongues. The article, “The measurement of regional cerebral blood flow during glossolalia: A preliminary SPECT study” [4] took five healthy women, psychiatrically stable, long term members of their churches, who had all spoken in tongues for many years. They scanned their brain activity after a period of singing to gospel songs in English and compared it to their brain activity after the same amount of time praying in tongues (while listening to the same music as before).

What they found was that the brain was more active in the left superior parietal lobe, while there was a decrease in brain activity in the prefrontal cortices, left caudate nucleus and left temporal pole. There was a trend for an increase in the activity of the right amygdala, but this may have just been chance.

So are any of those brain regions responsible for discernment as Dr Leaf suggested?

Well, that all depends on how you define “discernment”. “Discernment” is not really a common neurobiological term. The standard term in the literature is “judgement”. The brain regions that are associated with evaluation and judgement are the amygdala and ventral portions of the striatum as well as the ventromedial prefrontal cortex (vmPFC), orbitofrontal cortex (OFC), the insula, the dorsal anterior cingulate cortex (dACC), and the periaqueductal gray (PAG) [5].

Are there any parts of the brain that match in the two lists? Only one – the ventromedial prefrontal cortex, or vmPFC for short. The prefrontal cortex is important in reasoning and decision-making, especially if there is uncertainty or novelty, while the vmPFC in particular is involved in the use of goal-relevant information in guiding responses, e.g., assigning value to choice options [6].

According to Dr Leaf, “When we speak in tongues, research shows that the areas involved in discernment in the brain increase in activity”. But that’s certainly not what the research paper said. The actual research is entirely the opposite.

Again, there are really only two reasonable explanations as to why the research contradicts Dr Leaf; either there is another piece of research which supports Dr Leaf’s assertion, or Dr Leaf is simply wrong.

At the risk of repeating myself, Dr Leaf needs to quote her sources when she is writing her little social media memes. Her meme may be perfectly justified by robust scientific evidence, but if she isn’t willing to share her sources, we’ll never know, and the only conclusion remaining is that Dr Leaf can’t interpret simple research.

So as it stands, there really isn’t any evidence that speaking in tongues makes you more discerning. By trying to claim otherwise, Dr Leaf further undermines her own reputation and credibility as an expert.

References

Hine, V.H., Pentecostal glossolalia: towards a functional reinterpretation. Journal for the Scientific Study of Religion, 1969. 8: 212-26
Brende, J.O. and Rinsley, D.B., Borderline disorder, altered states of consciousness, and glossolalia. J Am Acad Psychoanal, 1979. 7(2): 165-88 http://www.ncbi.nlm.nih.gov/pubmed/370074
Persinger, M.A., Striking EEG profiles from single episodes of glossolalia and transcendental meditation. Perceptual and Motor Skills, 1984. 58: 127-33
Newberg, A.B., et al., The measurement of regional cerebral blood flow during glossolalia: a preliminary SPECT study. Psychiatry Res, 2006. 148(1): 67-71 doi: 10.1016/j.pscychresns.2006.07.001
Doré, B.P., et al., Social cognitive neuroscience: A review of core systems, in APA Handbook of Personality and Social Psychology, Mikulincer, M., et al., (Eds). 2014, American Psychological Association: Washington, DC. p. 693-720.
Nicolle, A. and Goel, V., What is the role of ventromedial prefrontal cortex in emotional influences on reason?, in Emotion and Reasoning, Blanchette, I., (Ed). 2013, Psychology Press.

STOP THE PRESSES! Dr Leaf releases a new meme based on my correction, still doesn’t acknowledge source. (13 November 2014)

So, I can’t find fault on what Dr Leaf said here. It fits with the paper I quoted from Newberg et al (2006). Still, it begs the question of why Dr Leaf couldn’t have said this in the first place, and why she still isn’t willing to share her citations?

It also raises the other obvious question, why is it important to know what our brain does in glossolalia? It’s only a study of 5 patients, and I’m sure that not all episodes of speaking in tongues is associated with decreased intentionality. The research, being so small, isn’t a true reflection of the practice of speaking in tongues. Lets hope that the future will bring more funding to better study this central tenet to the charismatic faith.

Dr Caroline Leaf: Putting thought in the right place

Posted on November 8, 2014 by cedwardpitt

Following hard on the heels of her false assumption that our minds control our health, not our genes, and following the same theme, Dr Leaf had this to say today, “Everything is first a thought; the brain is being controlled with EVERY thought you think!”

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. Reading back through my blogs, this “thought controls the brain / mind controls matter” is a recurrent theme of hers. It is repeated multiple times in her books, like when she writes, “Thoughts influence every decision, word, action and physical reaction we make.” [1: p13] and “Our mind is designed to control the body, of which the brain is a part, not the other way around. Matter does not control us; we control matter through our thinking and choosing” [2: p33] just as a couple of examples.

So how does thought relate to the grand scheme of our brain and it’s processing? Does our thought really control our brain, or is it the other way around. Through all of the reading that I have done on neuroscience, I propose a model of the place of thought in relation to the rest of our brains information processing. It is based on the LIDA model, dual systems models, and other neuroscientific principles and processes.

We’ve all heard the phrase, “It’s just the tip of the iceberg.” It comes from the fact that icebergs are made of fresh water, which is nine-tenths less dense than seawater. As a result, ten percent of an iceberg sits above the waters surface with most of it hiding beneath.

The information processing of our brains is much the same. We may be aware of our conscious stream of thought, but there is a lot going on under the surface that makes our thoughts what they are, even though we can’t see the process underneath.

What’s going on under the surface is a complex interplay of our genes and their expression which controls the structure and function of our brains, which effects how we perceive information, how we process that information and combine it into our memories of the past, predictions of the future, and even the further perception of the present [3].

Genes, epigenetics and the environment
We start with the most fundamental level of our biological system, which is genetics. It becomes clear from looking at any textbook of biological sciences that genes are fundamental to who we are. From the simplest bacteria, fungi, protozoans and parasites, through to all plants, all animals and all of human kind – EVERY living thing has DNA. DNA is what defines life in the broadest sense.

Proteins are responsible for the size, shape and operation of the cell. They make each tissue structurally and functionally different, but still work together in a highly precise electrochemical synchrony. But ultimately, it’s our genes that hold all of the instructions to make every one of the proteins within our cells. Without our genes, we would be nothing more than a salty soup of random amino acids.

Epigenetics and the environment contribute to the way genes are expressed. Epigenetics are “tags” on the strand of DNA that act to promote or silence the expression of certain genes (I discuss this in more detail in chapter 12 of my book, https://www.smashwords.com/books/view/466848). Environmental factors (the components that make up the world external to our bodies) can influence genes and epigenetic markers. The environment can cause genetic mutations or new epigenetic marks that change the function of a particular gene, and depending on which cell they effect (a very active embryonic cell or a quiet adult cell) will largely determine the eventual outcome. The environment is more influential to our genetic expression than epigenetics.

Still, on average only about 25% of the expression of a complex trait is related to environmental factors. So while the environment is important, it is still outdone 3:1 by our genome.

Yes, epigenetics and the environment are important, but they influence, not control, the genome.

Perception
We live in a sensory world. The five senses are vital in providing the input we need for our brain to understand the world and meaningfully interact with it.

Different organs are needed to translate the optical, chemical or mechanical signals into electrical signals. Different parts of our brain then interpret these signals and their patterns.

Our genes significantly influence this process. For example, if someone is born with red-green colour blindness then how he or she interprets the world will always be subtly different to someone with normal vision. Or a person born with congenital deafness will always interpret his or her environment in a different way to someone with full hearing. I’ve highlighted these two conditions because they provide stark examples to help demonstrate the point, but there are many unique genetic expressions in each of the five senses that subtly alter the way each of us perceives the world around us.

So while we may all have the same photons of light hitting our retinas, or the same pressure waves of sound reaching our ears or touch on our skin, how our brains receive that information is slightly different for every individual. The information from the outside world is received by our sensory organs, but it is perceived by our brain, and even small differences in perception can have a big impact on the rest of the system.

Personality
Personality is “the combination of characteristics or qualities that form an individual’s distinctive character” [4]. Formally speaking, personality is, “defined as constitutionally based tendencies in thoughts, behaviors, and emotions that surface early in life, are relatively stable and follow intrinsic paths of development basically independent of environmental influences.” [5]

Professor Gregg Henriques explained it well in Psychology Today, “Personality traits are longstanding patterns of thoughts, feelings, and actions which tend to stabilize in adulthood and remain relatively fixed. There are five broad trait domains, one of which is labeled Neuroticism, and it generally corresponds to the sensitivity of the negative affect system, where a person high in Neuroticism is someone who is a worrier, easily upset, often down or irritable, and demonstrates high emotional reactivity to stress.” [6] The other four personality types are Extraversion, Agreeableness, Conscientiousness, and Openness to Experience.

Gene x environment studies suggest that personality is highly heritable, with up to 60% of personality influenced by genetics [7], predominantly through genes involved in the serotonin [8] and dopamine systems [9, 10]. The “non-shared environment” (influences outside of the home environment) contributes heavily to the remainder [11, 12].

Personality is like a filter for a camera lens, shaping the awareness of our emotional state for better or worse, thus influencing the flow on to our feelings (the awareness of our emotions), our thoughts, and our actions.

Physiology
Watkins describes physiology as streams of data that are provided from the different parts of your body, like the heart rate, your breathing rate, the oxygen in your blood, the position of your joints, the movement of your joints, even the filling of your bladder telling you that you need a break soon.

All of these signals are constantly being generated, and collated in different parts of the brain. Some researchers consider them positive and negative depending on the data stream and the signal its providing. They coalesce into emotion [13].

Emotion
According to Watkins, “emotion” is the sum of all the data streams of physiology, or what he described as “E-MOTION … Energy in MOTION.” [13] In this context, think of emotion as a bulls-eye spirit-level of our body systems. The different forces of our physiology change the “level” constantly in different directions. Emotion is the bubble that marks the central point, telling us how far out of balance we are.

In the interest of full disclosure, I should mention that although emotion is a familiar concept, the work of literally thousands of brilliant minds has brought us no closer to a scientifically validated definition of the word “emotion”. Some psychologists and researchers consider it vague and unscientific, and would prefer that it not be used altogether [14].

I’ve retained it because I think it’s a well-recognised word that conceptually describes the balance of physiological forces.

Feelings
“Feelings” are the perception of emotion.

I discussed earlier in the chapter that what we perceive is different to what we “see” because the subtle genetic differences in our eyes and brains causes the information to be processed differently between individuals. The same applies to the perception of our emotion.

As I wrote earlier, personality is largely determined by our genetics with contributions from our environment [11, 12]. The emotional signal is filtered by our personality to give rise to our feelings. Classically, an optimistic personality is going to bias the emotional input in a positive, adaptive way while a pessimist or neurotic is going to bias the emotional signal in a maladaptive way

That’s not to say that an optimist can’t have depressed feelings, or a neurotic can’t have happy feelings. In the same way that a coloured lens will allow a lot of light through but filter certain wavelengths out, most of our emotional state of being will come through the filter of our personality but the feelings will be subtly biased one way or another.

Executive Functions
Executive function of the brain is defined as a complex cognitive process requiring the co-ordination of several sub-processes to achieve a particular goal [15]. These sub-processes can be variable but include working memory, attention, goal setting, maintaining and monitoring of goal directed action and action inhibition. In order to achieve these goals, the brain requires flexibility and coordination of a number of networks and lobes, although mainly the prefrontal cortex, parietal cortex, anterior cingulate and basal ganglia, and the while matter tracts that connect them.

Executive functions process the incoming information and decide on what goals are best given the context, then plan the goals, execute them to the motor cortices, and monitor the action. Research work from Marien et al [16] demonstrates that unconscious/implicit goals can divert resources away from conscious goals especially if it is emotionally salient or otherwise strongly related. They also confirm that conscious awareness is not necessary for executive function but that implicit goals can be formed and executed without conscious involvement.

Thoughts
Thoughts are essentially a stream of data projected into our conscious space. Baars [17, 18] noted that the conscious broadcast comes into working memory which then engages a wider area of the cerebral cortex necessary to most efficiently process the information signal. We perceive thought most commonly as either pictures or sounds in our head (“the inner monologue”), which corresponds to the slave systems of working memory. When you “see” an image in your mind, that’s the visuospatial sketchpad. When you listen to your inner monologue, that’s your phonological loop. When a song gets stuck in your head, that’s your phonological loop as well, but on repeat mode.

There is another slave system that Baddeley included in his model of working memory called the episodic buffer, “which binds together complex information from multiple sources and modalities. Together with the ability to create and manipulate novel representations, it creates a mental modeling space that enables the consideration of possible outcomes, hence providing the basis for planning future action.” [19]

Deep thinking is a projection from your brains executive systems (attention or the default mode network) to the central executive of working memory, which then recalls the relevant information from long-term memory and directs the information through the various parts of the slave systems of working memory to process the complex details involved. For example, visualizing a complex scene of a mountain stream in your mind would involve the executive brain directing the central executive of working memory to recall information about mountains and streams and associated details, and project them into the visuospatial sketchpad and phonological loop and combine them via the episodic buffer. The episodic buffer could also manipulate the scene if required to create plans, or think about the scene in new or unexpected ways (like imagining an elephant riding a bicycle along the riverbank).

Even though the scene appears as one continuous episode, it is actually broken up into multiple cognitive cycles, in the same way that images in a movie appear to be moving, but are really just multiple still frames played in sequence.

Action
Action is the final step in the process, the output, our tangible behaviour

Our behaviour is not the direct result of conscious thought, or our will (as considered in the sense of our conscious will).

We discussed this before when we talked about our choices in chapter 1. There are two main pathways that lead from sensory input to tangible behaviour – various automated pathways that take input from the thalamus, deep in the brain, and sent to motor circuits in the supplementary motor area and motor cortex of the brain. These can be anything from evasive “reflex” actions[1] to rehearsed, habituated motor movements, like driving. Then there is the second pathway, coming from the executive areas of our brain, that plan out options for action, which are reviewed by the pre-supplemental motor area and the default mode network.

This second pathway is amenable to conscious awareness. Like thought, the projection of different options for action into our consciousness helps to engage a wider area of cerebral cortex to process the data. Most of the possible plans for action have already been rejected by the implicit processing of our executive brain before consciousness is brought in to help. Once an option has been selected, the action is sent to the pre-supplementary motor area, the supplementary motor area, the basal ganglia and finally the motor cortex.

According to the model proposed by Bonn [20], the conscious network has some feedback from the control network of our brain, providing real time context to actions about to be executed, and a veto function, stopping some actions at the last minute before they are carried out. This is largely a function of the basal ganglia [21], with some assistance from working memory.

So as you can see, according to the CAP model, conscious thoughts are one link of a longer chain of neurological functions between stimulus and action – simply one cog in the machine. Thoughts are dependent on a number of processes that are both genetically and environmentally determined, beyond our conscious control. It’s simply wrong to assume that thoughts control the brain.

Dr Leaf is welcome to her opinion, but it is in contradiction to the overwhelming majority of neuroscientific knowledge

References

Leaf, C., Who Switched Off My Brain? Controlling toxic thoughts and emotions. 2nd ed. 2009, Inprov, Ltd, Southlake, TX, USA:
Leaf, C.M., Switch On Your Brain : The Key to Peak Happiness, Thinking, and Health. 2013, Baker Books, Grand Rapids, Michigan:
Hao, X., et al., Individual differences in brain structure and resting brain function underlie cognitive styles: evidence from the embedded figures test. PLoS One, 2013. 8(12): e78089 doi: 10.1371/journal.pone.0078089
Oxford Dictionary of English – 3rd Edition, 2010, Oxford University Press: Oxford, UK.
De Pauw, S.S., et al., How temperament and personality contribute to the maladjustment of children with autism. J Autism Dev Disord, 2011. 41(2): 196-212 doi: 10.1007/s10803-010-1043-6
Henriques, G. (When) Are You Neurotic? Theory of Knowledge: Psychology Today; 2012, 23 Nov 2012 [cited 2013 23 Nov 2012]; Available from: http://www.psychologytoday.com/blog/theory-knowledge/201211/when-are-you-neurotic.
Vinkhuyzen, A.A., et al., Common SNPs explain some of the variation in the personality dimensions of neuroticism and extraversion. Transl Psychiatry, 2012. 2: e102 doi: 10.1038/tp.2012.27
Caspi, A., et al., Genetic sensitivity to the environment: the case of the serotonin transporter gene and its implications for studying complex diseases and traits. Am J Psychiatry, 2010. 167(5): 509-27 doi: 10.1176/appi.ajp.2010.09101452
Felten, A., et al., Genetically determined dopamine availability predicts disposition for depression. Brain Behav, 2011. 1(2): 109-18 doi: 10.1002/brb3.20
Chen, C., et al., Contributions of dopamine-related genes and environmental factors to highly sensitive personality: a multi-step neuronal system-level approach. PLoS One, 2011. 6(7): e21636 doi: 10.1371/journal.pone.0021636
Krueger, R.F., et al., The heritability of personality is not always 50%: gene-environment interactions and correlations between personality and parenting. J Pers, 2008. 76(6): 1485-522 doi: 10.1111/j.1467-6494.2008.00529.x
Johnson, W., et al., Beyond Heritability: Twin Studies in Behavioral Research. Curr Dir Psychol Sci, 2010. 18(4): 217-20 doi: 10.1111/j.1467-8721.2009.01639.x
Watkins, A. Being brilliant every single day – Part 1. 2012 [cited 2 March 2012]; Available from: http://www.youtube.com/watch?v=q06YIWCR2Js.
Dixon, T., “Emotion”: The History of a Keyword in Crisis. Emot Rev, 2012. 4(4): 338-44 doi: 10.1177/1754073912445814
Elliott, R., Executive functions and their disorders Imaging in clinical neuroscience. British Medical Bulletin, 2003. 65(1): 49-59
Marien, H., et al., Unconscious goal activation and the hijacking of the executive function. J Pers Soc Psychol, 2012. 103(3): 399-415 doi: 10.1037/a0028955
Baars, B.J. and Franklin, S., How conscious experience and working memory interact. Trends Cogn Sci, 2003. 7(4): 166-72 http://www.ncbi.nlm.nih.gov/pubmed/12691765 ; http://bit.ly/1a3ytQT
Baars, B.J., Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research, 2005. 150: 45-53
Repovs, G. and Baddeley, A., The multi-component model of working memory: explorations in experimental cognitive psychology. Neuroscience, 2006. 139(1): 5-21 doi: 10.1016/j.neuroscience.2005.12.061
Bonn, G.B., Re-conceptualizing free will for the 21st century: acting independently with a limited role for consciousness. Front Psychol, 2013. 4: 920 doi: 10.3389/fpsyg.2013.00920
Beste, C., et al., Response inhibition subprocesses and dopaminergic pathways: basal ganglia disease effects. Neuropsychologia, 2010. 48(2): 366-73 doi: 10.1016/j.neuropsychologia.2009.09.023

[1] We often describe rapid unconscious movements, especially to evade danger or to protect ourselves, as “reflexes”. Medically speaking, a true reflex is a spinal reflex, like the knee-jerk reflex. When a doctor taps the knee with the special hammer, the sudden stretch of the tendon passes a nerve impulse to the spinal cord, which is then passed to the muscle, which makes it contract. A true reflex doesn’t go to the brain at all.

Dr Caroline Leaf and the matter of mind over genes

Posted on November 7, 2014 by cedwardpitt

I think I might have to throw away my genetics textbook.

I was always taught that genes were the main driver behind health and disease, and I always thought it was a pretty good theory.

But not according to Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist, who said on her social media feeds today, “Our health is not controlled by genetics – our health is controlled by our mind.”

Taking her statement at face value, she appears to be saying that genes have nothing to do with our health. Dr Leaf has made some asinine statements in the past, but to suggest that genes are irrelevant to human health seemed so stupid that no one in their right mind would suggest such a thing.

Perhaps I was taking her statement the wrong way? I wanted to make sure I didn’t jump to any rash conclusions about Dr Leaf’s statement, so I pondered it at length. Could she be referring to ‘control’ in the absolute sense? How much control do genes have on our health? What about the mind?

After deliberating for a while, I still came to the conclusion that Dr Leaf’s statement was nonsense.

Unfortunately, Dr Leaf’s statement is, like so many of her previous Facebook memes, so vague as to be misleading. The meaning of ‘health’ and ‘controlled’ could be taken so many ways … which part of our health? How much regulation constitutes ‘control’? What about genetics?

Looking at her statement in more depth, it becomes clear that no matter which way Dr Leaf meant it, it’s still wrong. For example, all of human health is controlled, in part, by genetics. That’s because life itself is controlled by genetics. The human genome provides a blueprint for the construction of all of the proteins in all of the cells in our entire body. The expression of those genes determines exactly how our body will run. If the genes are wrong, if the translation of the gene code into a protein is wrong, or if too much or too little of a protein is made, all determines whether our body is functioning at its optimum level or not.

The stimulus for the expression of our genes is influenced by the environment in which we live. If I go out into the sun a lot, the UV light triggers my skin cells to make the protein melanin, which makes my skin go darker and helps to provide some protection against the damaging effects of the UV light.

While the environment plays a part of the expression of some genes, it’s wrong to say that genetics doesn’t control the process. If I go into the sun too much, I risk developing a melanoma, because the sun damages the genes in some of my skin cells, causing them to grow without control.

Genes are still responsible for the disease itself. Sometimes the trigger is from the environment, sometimes it’s not. There are some people with genes for melanoma who don’t need an environmental trigger, because they develop melanoma on skin that’s exposed to very little UV light, like the genital skin.

So fundamentally, even taking the environment into account, our health is controlled by our genetics.

The other part of Dr Leaf’s meme is also wrong. Our health is not controlled by our mind. Our genes are influenced by “the environment”, which according to the seminal paper by Ottman, “The environmental risk factor can be an exposure, either physical (e.g., radiation, temperature), chemical (e.g., polycyclic aromatic hydrocarbons), or biological (e.g., a virus); a behavior pattern (e.g., late age at first pregnancy); or a “life event” (e.g., job loss, injury). This is not intended as an exhaustive taxonomy of risk factors, but indicates as broad a definition as possible of environmental exposures.” [1]

Even if one considers the mind as part of the sub classification of “a behavior pattern”, it’s still pretty clear that most of the factors that make up our environment are not related to our mind at all but are related to the external world, of which we have minimal or no control over. Sure, we make choices, but our choices aren’t truly free. They’re constrained by the environment in which we find ourselves. In the same way, our mind may have some tiny influence on our health, but only insofar as our environment and our genes will allow.

When it all boils down, this meme of Dr Leaf’s is rested on her foundational presumption that our mind can control matter, a very strong theme throughout her most recent book [2], but which is still preposterous. Our thoughts are simply a function of our brain, which is in turn determined by the function of our nerve cells, which is in turn a function of our genes and their expression.

Our mind doesn’t control matter. Matter controls our mind.

I can keep my genetics textbooks after all.

References

Ottman, R., Gene-environment interaction: definitions and study designs. Prev Med, 1996. 25(6): 764-70 http://www.ncbi.nlm.nih.gov/pubmed/8936580
Leaf, C.M., Switch On Your Brain : The Key to Peak Happiness, Thinking, and Health. 2013, Baker Books, Grand Rapids, Michigan:

Understanding Thought – Part 3

Posted on October 27, 2014 by cedwardpitt

What is thought?

We’re all familiar with thought, to be sure, just like we’re familiar with our own bodies. But just because we know our own bodies doesn’t make us all doctors. In the same way, we might know our own thoughts well, but that doesn’t make us experts in the science of thought.

This series of blogs is taken from my book Hold That Thought: Reappraising the work of Dr Caroline Leaf. We’ve looked at some basic neurobiology and the neurobiology of thought itself. Today we’ll discuss some psychological models of our thought processing, and the common brain states and functions that are usually confused with thought.

Other cognitive frameworks of thought

Dual Systems

A number of models of thought use a dual systems approach, explaining our cognitive process in terms of two systems.

System 1 involves a set of different subsystems that operate in parallel, delivering swift and intuitive judgments and decisions in response to our perceptions. System 1 is unconscious, automatic and guided by principles that are, to a significant extent, innately fixed and universal among humans.

System 2 is the system that involves “thought” as people typically think about it. It is both conscious and reflective in character, and proceeds in a slow, serial manner, according to principles that vary among both individuals and cultures [1]. This system is in harmony with the Global Workspace/LIDA concept of the cognitive cycle.

System 2 is generally held to be subject to intentional control, hence why thoughts can be volitional. System 2 can be guided by normative beliefs about proper reasoning methods. In other words, we can learn ways of thinking about our thoughts to handle them better. And one of the principal roles often attributed to system 2 is to override the unreflective responses that are issued automatically by system 1 in reasoning tasks, when these fall short of appropriate standards of rationality. We can use thought to modulate or suppress our intuitive responses, the concept of “think before you act”.

Neuroscience research confirms the neural networks involved with the dual systems, and have taken the theory further [2]. Not only can stimuli that are emotionally significant activate the lower, emotional parts of our brain, they can do so without us ever being consciously aware they were detected. For example, when test subjects had their visual cortex temporarily stunned by a transcranial magnetic stimulator, they could detect whether a face was happy or sad and even where it was on a grid without consciously sensing that they had “seen” a face [3]. Subconscious emotional stimuli can modulate our attention before we are aware of their perception [4].

Relational Frame Theory / Acceptance And Commitment Therapy

Relational frame theory, and the clinical approach based on it called Acceptance and Commitment Therapy, sees thoughts as contextual. This is interesting, as new neurobiological approaches such as neurocognitive networks are also girded by the developing view of cognition which is that cognition “is marked by both dynamic flexibility and context sensitivity.” [5]

Relational frame theory posits that “the core of human language and cognition is learning to relate events mutually and in combination not simply on the basis of their formal properties (e.g., size, shape) but also on the basis of arbitrary cues.” [6] Basically, we understand things in both concrete and abstract ways. “The gold coin is small” is referring to the tangible properties of the gold coin. “The gold coin is very valuable” is referring to the arbitrary properties of the gold coin, which are values that we define in our minds.

Hayes states, “A key RFT insight of clinical importance is that relational framing is regulated by two distinguishable features: the relational context and the functional context … The relational context determines what you think; the functional context determines the psychological impact of what you think.” [6]

So in terms of thought, what we think isn’t necessarily reliable. It’s contextual, and often abstract and arbitrary. The meanings and values that are placed on our thoughts are related to the context in which they came to us, and the impact is also arbitrary, a function of our minds and our language.

As William Shakespeare wrote, “for there is nothing either good or bad, but thinking makes it so.” [7] Thoughts are just that – thoughts. So while there is a mountain of published literature on “negative” or “positive” thoughts, such distinctions are subjective, arbitrary, and often entirely unhelpful.

We often become fused to the meaning of our thoughts. We begin to take them literally, without noticing the process of thinking itself. When the thoughts become painful, we don’t know how to handle them, and we run from them, or try to suppress them. But in fighting with the thoughts, we actually draw attention to them and make them more powerful. This makes them even more painful, and makes the avoidance worse. We then lose flexible contact with the present moment, as we become more and more consumed with the internal battle with our painful thoughts and subsequent emotions. Rather than looking around us, all we can do is focus on the pain or be anywhere else where difficult events are not occurring. [6]

The key in this battle is not to engage with the “negative” thoughts by pushing them away or trying to change them. Pushing the painful thoughts away makes them go away for a while, but it takes a lot of effort. The thoughts return as we tire, but we have less energy to resist them.

Try holding a fully inflated basketball under water. It’s possible, but the basketball wants to get back to the surface. Holding it down is hard work. You usually can’t do it for long. Fighting our thoughts is the same.

Harris describes the focus of Acceptance and Commitment Therapy, “around two main processes: developing acceptance of unwanted private experiences which are out of personal control, commitment and action towards living a valued life … In ACT, there is no attempt to try to reduce, change, avoid, suppress, or control these private experiences. Instead, clients learn to reduce the impact and influence of unwanted thoughts and feelings, through the effective use of mindfulness.” [8]

The first principle of ACT is to start treating thoughts as what they really are … just thoughts. This is simply done by learning to observe the process of thinking again, to realise that the words going through our minds are just words. They only have the meaning that we give to them. They only have the power that we allow them to have.

The key to overcoming thought patterns we don’t want isn’t to change them, it’s to remove their power. Trying to change them means engaging with them, which only makes them stronger. Disempowering them means seeing them for what they are. They may sound like Rottweiler’s but when you actually look, they’re more like Chihuahua’s with megaphones. When you understand that your thoughts are not in control, you can move forward into the actions that really bring change. If you want to know more about ACT, or you would like to use ACT to help stop fighting your thoughts, there are a number of free resources that are a great starting point = http://www.actmindfully.com.au/free_resources

What is, and is not, a thought?

Thought, therefore, is simply a broadcast of one part of a deeper flow of information. Thought is not a controlling force. It’s not a case of, “I think, therefore, I am”, but, “I am, therefore, I think.”

Thoughts are often described in the peer-reviewed publications as the “stream of thought” or the “stream of consciousness”. According to Baars and Franklin, thoughts arise from the broadcast step of multiple cognitive cycles, but the conscious broadcast of our thought stream is limited to a single cognitive cycle at any given instant. Thus, even though it is considered a “stream”, our awareness of our thought is in a serial, sometimes disparate, sequence of frames [9].

There are some features of our stream of thought that differentiate it from other brain activity. We have a level of voluntary control over our stream of thought, even if it’s not direct [10]. It is also characterized by a metacognitive level – we have “thinking about thinking” [1, 11], and we have “awareness of awareness” [12].

Yet there are still many neurological functions that are confused with thoughts.

Brain activity

“Thoughts” are often confused for any brain activity. The stream of thought is sometimes referred to as the “stream of consciousness” but that’s a misnomer.

Consciousness has varying levels (coma, deep sleep, lucid dreaming, awake, and alert). Only some of these levels of consciousness allow thought. Therefore, it would be fair to say that thoughts are a form of activity of the brain, just like Toyotas are a form of car.

Brain activity is largely subconscious. It carries on in the background without our awareness [2]. There are multiple simultaneous streams of data being perceived all the time – sensation from our ears, skin, eyes and internal organs – that our brain filters out before it reaches our awareness. Background traffic noise, the pressure of your clothes on your skin, joint position, heart rate and breathing, for example. It’s not that these sensations are not present, but you only become aware of them when your attention is drawn to them. Those data streams are not thoughts in and of themselves because we lack awareness of them. They only become part of our thoughts when attention is paid to them. Since thoughts are characterized by metacognition, “awareness of awareness”, then neural activity we aren’t aware of cannot be considered thoughts.

The other problem with defining all brain activity as “thought” is that such as definition would also mean that seizures were thoughts, or brainstem reflexes were thoughts. We intuitively know that’s not the case.

Dreams

So what about dreams? We’re aware of dreams, aren’t we? Could dreams be considered thoughts?

Dreams are awareness of perception and emotion, similar to our state of awareness when we’re awake. But dreams occur in an altered state of consciousness (that is, we are asleep). Dreams also lack self-awareness. When you dream, you don’t realise that you’re dreaming. Secondary consciousness, the level of consciousness that we possess when we are awake, is defined in part as having awareness of awareness. It is more than just having awareness of perception and emotion. It is “self-reflection, insight, judgment or abstract thought that constitute secondary consciousness.” [12]

Memories

As I wrote earlier, memories aren’t just simple recall, but a complex system involving both conscious and unconscious elements. The conscious elements of memory are simply stored representations of events and experiences. They may become part of a thought broadcast, but they are not thoughts per se.

References

Fletcher, L. and Carruthers, P., Metacognition and reasoning. Philos Trans R Soc Lond B Biol Sci, 2012. 367(1594): 1366-78 doi: 10.1098/rstb.2011.0413
Tamietto, M. and de Gelder, B., Neural bases of the non-conscious perception of emotional signals. Nat Rev Neurosci, 2010. 11(10): 697-709 doi: 10.1038/nrn2889
Jolij, J. and Lamme, V.A., Repression of unconscious information by conscious processing: evidence from affective blindsight induced by transcranial magnetic stimulation. Proc Natl Acad Sci U S A, 2005. 102(30): 10747-51 doi: 10.1073/pnas.0500834102
Ohman, A., et al., Emotion drives attention: detecting the snake in the grass. J Exp Psychol Gen, 2001. 130(3): 466-78 http://www.ncbi.nlm.nih.gov/pubmed/11561921
Meehan, T.P. and Bressler, S.L., Neurocognitive networks: findings, models, and theory. Neurosci Biobehav Rev, 2012. 36(10): 2232-47 doi: 10.1016/j.neubiorev.2012.08.002
Hayes, S.C., et al., Acceptance and commitment therapy and contextual behavioral science: examining the progress of a distinctive model of behavioral and cognitive therapy. Behav Ther, 2013. 44(2): 180-98 doi: 10.1016/j.beth.2009.08.002
Shakespeare, W., Hamlet, Act II, Scene 2.
Harris, R., Embracing Your Demons: an Overview of Acceptance and Commitment Therapy. Psychotherapy In Australia, 2006. 12(6): 1-8 http://www.actmindfully.com.au/upimages/Dr_Russ_Harris_-_A_Non-technical_Overview_of_ACT.pdf
Franklin, S., et al., Conceptual Commitments of the LIDA Model of Cognition. Journal of Artificial General Intelligence, 2013. 4(2): 1-22
Bonn, G.B., Re-conceptualizing free will for the 21st century: acting independently with a limited role for consciousness. Front Psychol, 2013. 4: 920 doi: 10.3389/fpsyg.2013.00920
Scott, B.M., Levy, M. G., Metacognition: Examining the components of a fuzzy concept. Educational Research eJournal, 2013. 2(2): 120-31 doi: 10.5838/erej.2013.22.04
Hobson, J.A., REM sleep and dreaming: towards a theory of protoconsciousness. Nat Rev Neurosci, 2009. 10(11): 803-13 doi: 10.1038/nrn2716

Understanding Thought – Part 2, The Neuroscience of Thought

Posted on October 24, 2014 by cedwardpitt

What is thought?

But understanding thought is important. If we don’t know what thoughts are, then it’s very easy to be conned into believing the myriad of myths about thought perpetuated about them by every pop-psychologist and B-grade life coach. This series of blogs is taken from my book Hold That Thought: Reappraising the work of Dr Caroline Leaf.

We’ve looked at some basic neurobiology, and today we’ll look at the neurobiology of thought itself. Later we’ll discuss some psychological models of our thought processing, and finally we’ll discuss the common brain states and functions that are usually confused with thought.

Neuroscience of thought

Global Workspace / Intelligent Distribution Agent Model

Building on Baddeley’s model of working memory, Baars proposed the Global Workspace theory [1], and Baars and Franklin went further by adding the Intelligent Distribution Agent model [2]. Central to this model is the “Cognitive cycle”, a nine-step description of the underlying process from perception through to action. In the model, implicit neural information processing is considered to be a continuing stream of cognitive cycles, overlapping so they act in parallel. The conscious broadcast of our thought stream is limited to a single cognitive cycle at any given instant, so while these thought cycles run in in parallel, our awareness of them is in the serial, sometimes disparate, streams of words or pictures in our minds. Baars and Franklin suggests that as many as ten cycles could be running per second [3], and since working-memory tasks occur on the order of seconds, several cognitive cycles may be needed for any given working memory task, especially if it has conscious components such as mental rehearsal [2].

In recent years, the Global Workspace/Intelligent Distribution Agent hypothesis has been updated to help facilitate the quest to create different forms of artificial intelligence. The LIDA (“Learning Intelligent Distribution Agent”) model incorporates the Global Workspace theory with the concepts of memory formation to create a single, broad, systems-level model of the mind.

Franklin et al summarise the process, “During each cognitive cycle the LIDA agent first makes sense of its current situation as best as it can by updating its representation of its current situation, both external and internal. By a competitive process, as specified by Global Workspace Theory, it then decides what portion of the represented situation is the most salient, the most in need of attention. Broadcasting this portion, the current contents of consciousness, enables the agent to chose an appropriate action and execute it, completing the cycle.” [4] Information within the cognitive cycle is broadcast to our consciousness in order to recruit a wider area of the brain to enhance the processing of that information [2, 5]. It’s the broadcasting of this portion of the information flow that renders it “conscious”.

Thought, therefore, is simply a broadcast of one part of a deeper flow of information. This is very important, as it means that thought is not an instigator or a controlling force. It’s not a case of, “I think, therefore, I am”, but, “I am, therefore, I think.”

Neural networks involved in the neurobiology of thought?

There is good evidence that working memory, and the attention required to select the information streams that fill the global workspace at any one moment, are intrinsically linked to a group of brain regions tagged as the Prefrontal Parietal Network [6]. Disease or damage to the PPN or impairment of the PPN in the lab impairs normal conscious function. Research-level brain imaging studies have strongly implicated the PPN in perceptual transitions, the conscious detection of stimuli in a range of modalities, sustaining percepts, and in metacognitive decisions (awareness of awareness) on those percepts. Finally, a reduction of conscious level when under general anesthesia is associated with a reduced lateral prefrontal activity [6].

Other neural networks have been defined that are also important in the neurophysiology of conscious awareness. When there are no external stimuli, the brain doesn’t just turn off. Some parts of the brain become even more active. The same parts of the brain are active when we daydream (what researchers call “stimulus independent thought”).

We have all experienced this at some point. Our body will be doing something while our brain is off somewhere else. I find this happens to me when I’m driving home from work. Going the same route every day means that I often drift into autopilot as I’m thinking about the events of the day or my stomach reminds me that I’m hungry, and five minutes later I pay attention to my surroundings and realise that I’m nearly home.

There are many other sentinel neurocognitive networks, among them: the default mode network, the central executive network, and the salience network. The central executive network is involved in actively working on an external task, which we think of as attention. The default mode network is involved in autobiographical retrieval and self-monitoring activity, the “stimulus independent thought”, or day-dreaming. The salience network acts as a switch between the two, figuring out which external stimuli need active attention and switching on the central executive network [7]. Whichever one of these networks is active at the time, that network is actively feeding information into the working memory, which is what we perceive as “thought”.

When the brain is engaged in a new or difficult task requiring active attention, the executive parts of the brain overtake the default mode network. But when attention is not actively required such as well-practiced tasks, or if our attention diminishes as with boring tasks, the Default Mode Network becomes dominant again. The switch between attention and the default mode network is strongly related to the neurotransmitter dopamine [8]. These networks heavily overlap with the Prefrontal Parietal Network and the global workspace model.

Recent neurobiological evidence confirms the role the default mode network in thought processing, specifically the part of the brain called the cingulate cortex. This has been confirmed in studies in healthy subjects [9], and in people with formal thought disorders (especially auditory verbal hallucinations) [10]. Specifically, the DMN is often the part of the brain that is the most active in remembering the past, and using similar mechanisms, also the simulations of the future. It is linked to daydreaming and creativity especially when a problem is allowed to “incubate” for a while, while the brain is involved in another task that is more menial, or low stress. It’s theorised that the attentional and implicit networks in the brain are brought into a closer proximity and allowed to interact, which improved the likelihood that a novel solution would be discovered [11].

Research into the topics of thought and consciousness is ever-growing and expanding, and if you want to read more about these topic, they have been very well covered in a two part series from De Sousa, [12] and [13].

References

Baars, B.J., A cognitive theory of consciousness. 1988, Cambridge University Press, Cambridge England ; New York:
Baars, B.J. and Franklin, S., How conscious experience and working memory interact. Trends Cogn Sci, 2003. 7(4): 166-72 http://www.ncbi.nlm.nih.gov/pubmed/12691765 ; http://bit.ly/1a3ytQT
Madl, T., et al., The timing of the cognitive cycle. PLoS One, 2011. 6(4): e14803 doi: 10.1371/journal.pone.0014803
Franklin, S., et al., Conceptual Commitments of the LIDA Model of Cognition. Journal of Artificial General Intelligence, 2013. 4(2): 1-22
Baars, B.J., Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research, 2005. 150: 45-53
Bor, D. and Seth, A.K., Consciousness and the prefrontal parietal network: insights from attention, working memory, and chunking. Front Psychol, 2012. 3: 63 doi: 10.3389/fpsyg.2012.00063
Meehan, T.P. and Bressler, S.L., Neurocognitive networks: findings, models, and theory. Neurosci Biobehav Rev, 2012. 36(10): 2232-47 doi: 10.1016/j.neubiorev.2012.08.002
de Wit, S., et al., Reliance on habits at the expense of goal-directed control following dopamine precursor depletion. Psychopharmacology (Berl), 2012. 219(2): 621-31 doi: 10.1007/s00213-011-2563-2
Shackman, A.J., et al., The integration of negative affect, pain and cognitive control in the cingulate cortex. Nat Rev Neurosci, 2011. 12(3): 154-67 doi: 10.1038/nrn2994
Lutterveld, R.v., et al., Network analysis of auditory hallucinations in nonpsychotic individuals, in Auditory verbal hallucinations and the brain, Lutterveld, R.v., (Ed). 2013, University Medical Center Utrecht: The Netherlands. p. 117-37.
Baird, B., et al., Inspired by distraction: mind wandering facilitates creative incubation. Psychol Sci, 2012. 23(10): 1117-22 doi: 10.1177/0956797612446024
De Sousa, A., Towards an integrative theory of consciousness: part 1 (neurobiological and cognitive models). Mens Sana Monogr, 2013. 11(1): 100-50 doi: 10.4103/0973-1229.109335
De Sousa, A., Towards an integrative theory of consciousness: part 2 (an anthology of various other models). Mens Sana Monogr, 2013. 11(1): 151-209 doi: 10.4103/0973-1229.109341

Dr Caroline Leaf and the mistruth done three ways.

Posted on October 23, 2014 by cedwardpitt

“Every thought you think impacts every one of the 75-100 trillion cells in your body at quantum speeds!” – Dr Caroline Leaf

I was going to stick to my series on thoughts over the next few days, but Dr Leafs social media gem today was so farcical and fanciful, I had to briefly comment on it.

Dr Caroline Leaf is a communication pathologist and self-titled cognitive neuroscientist. She is ‘flexible’ with the truth when she blogs or posts on social media. It’s never really quite clear exactly where the facts end and the generous ‘poetic licence’ begins. Of course, she never references any of her posts, so it’s anyone’s guess as to how she arrived at the statement in the first place.

Today’s offering is a typical example. It’s a breathless melding of some exaggerated statements, impressive sounding numbers, and a brief reference to a science which sounds catchy but that not even physicists fully understand. It is a master class in taking a concept that’s scientifically incorrect and making it sound like a Nobel Prize winning idea.

Lets breaking it down into its different components and analyse their validity separately:
“Every thought you think impacts … every cell in your body …”
“… every one of the 75-100 trillion cells in your body …”
“… at quantum speeds!”

“Every thought you think impacts … every cell in your body …”

This is the core part of Dr Leaf’s statement. Like most of Dr Leaf’s teaching on our thoughts, her definition of thoughts is incorrect, as is the place of thoughts in the neuro-informational processing schema. Our streams of thought are just slivers of information projected from the deeper regions of the brain into to a wider area of our cerebral cortex. The brain uses this process to analyse the information to a higher degree before acting on it or sending it into memory.

Our thoughts are nothing special. They’re just a small cog in a much larger machine. They do not have any influence beyond what the rest of the brain would allow [1].

Thoughts certainly don’t influence every cell in our body. They physically can’t. Cells are not connected to every other cell in the body

Even if they were connected, it doesn’t make sense that our thoughts influence every other cell. The hyperbole verges on the ridiculous. As if a random fibroblast in the tip of my 5th pinkie toe was significantly influenced by the thought that I had when I felt like chicken for dinner. Dr Leaf’s assertion that, “Every thought you think impacts … every cell in your body”, is a nonsense statement.

“… every one of the 75-100 trillion cells in your body …”

How many cells do you really have in your body? I’ve never really tried to count them all myself, but according to the Smithsonian in Washington, USA, there are only 37.2 trillion (http://www.smithsonianmag.com/smart-news/there-are-372-trillion-cells-in-your-body-4941473/?no-ist). The fact that Dr Leaf has so badly estimated, when all she needed to do was a one line Google search, suggests that she just made the number up. Out of respect to Dr Leaf, she really needs to reference her facts or she will continue to lose credibility,

“… at quantum speeds.”

Quantum physics remains largely mysterious even to those physicists who study it. So it’s a brave person who invokes the “quantum” word in any statement.

It appears that most scientists believe that the maximum quantum speed is the speed of light (http://www.wired.com/2012/01/quantum-information-speed/) so Dr Leaf believes that thought works at light speed. Interesting, because any communication between distant cells in the body is done through electrical transmission or signalling via hormones, which is certainly not at light speeds.

So thought doesn’t talk to our 37.2 trillion cells or even significantly impact them. It can’t. Thought doesn’t control our physiology or our actions, and our body does not work at light speed.

Dr Leaf seems to be largely basing her statement on theory that she has derived from a paper called “Local and nonlocal effects of coherent heart frequencies on conformational changes of DNA”, which suggested that deep love meditation changed some DNA’s ability to wind and unwind. They suggest that the same meditation can change DNA from 3 miles away. Except … that study is deeply flawed. (see my blog on the subject )

So ultimately, Dr Leaf has just published a social media post which has no scientific basis whatsoever. I would suggest that her followers deserve something better than some flighty, exaggerated puff-piece.

References

Pitt, C.E., Hold That Thought: Reappraising the work of Dr Caroline Leaf, 2014 Pitt Medical Trust, Brisbane, Australia, URL http://www.smashwords.com/books/view/466848

Understanding Thought – Part 1

Posted on October 23, 2014 by cedwardpitt

WHAT IS THOUGHT?

This series of blogs is taken from my book Hold That Thought: Reappraising the work of Dr Caroline Leaf. We will look at some basic neurobiology first, then look at the neurobiology of thought itself. We’ll discuss some psychological models of our thought processing, and finally we’ll discuss the common brain states and functions that are usually confused with thought.

Neurobiology 101

The nerve cell

At the most fundamental level of our thought process is the nerve cell, also called a neuron. Nerve cells, like all cells in the body, have a nucleus containing the genetic material. The nucleus is surrounded by cytoplasm, a watery chemical soup that contains the functional proteins that make the cell run. A thin lipid layer called the cell membrane envelopes the nucleus and cytoplasm. The cell membrane contains important protein structures such as receptors that help the cell receive signals from other cells, and ion channels, which help the cell regulate its internal chemistry.

Compared to other cells, nerve cells have three unique structures that help them do their job. First are dendrites, which are spiny branches that protrude from the main cell body, which receive the signals from other nerve cells. Leading away from the cell body is a long thin tube called an axon which helps carry electrical signal from the dendrites, down to the some tentacle-like processes that end in little pods. These pods, called the terminal buttons of the axon, and then convey the electrical signal to another nerve cell by directing a burst of chemicals towards the dendrites of the next nerve cell in the chain.

In order for the signal to be successfully passed from the first nerve cell to the second, it must successfully traverse a small space called the synapse.

The synapse

Despite being very close to each other, no nerve cell touches another. Instead, the spray of chemicals that’s released from the terminal button of the axon floats across a space of about 20-40nM (a nanometre is one billionth of a metre).

There are a number of different chemicals that traverse synapses, but each terminal button has its own particular one. The most well known are serotonin, noradrenaline and dopamine.

If the signal from the first nerve is strong enough, then a critical amount of the chemical is released and will make it across the gap to the dendrites of the second nerve cell on the other side. The chemical interacts with specific receptors on the new dendrites, which cause them to open up to certain salts like sodium and potassium. As sodium and potassium move in and out of the cell, a new electrical current if formed in the second nerve cell, passing the signal down the line.

To prevent the chemicals in the synapse from over-stimulating the second nerve cell, enzymes breakdown the chemicals to clear the space before the next signal comes past.

Nerve pathways

Combining nerve cells and synapses together creates a nerve pathway, where the input signal is received by specialised nerve endings and is transmitted down the nerve cell across a synapse to the next nerve cell, across the next synapse to the next nerve cell, and on and on until the signal has reached the destination for the output of that signal.

And that’s it. The entire nervous system is just a combination of nerve cells and the synapses between them.

What gives the nervous system and brain the near-infinite flexibility, and air of mystery, is that there are eighty-six billion nerve cells in the average adult (male) brain. Each nerve cell has hundreds to thousands of synapses. It’s estimated that there are about 0.15 quadrillion (that’s 150,000,000,000,000) synapses throughout the average brain [1]. And that’s not including the nerve cells and synapses in the spinal cord, autonomic nervous system and throughout the body. Each of these cells and synapses connect in multiple directions and levels, and transmit signals through the sum of the exciting or inhibiting influences they receive from, and pass on to, other nerve cells.

Single nerve cells may have the appearances of trees with their axon trunks and dendritic branches. But altogether, the billions of connections would more resemble a box of cobwebs.

Higher order brain structures

But unlike a box of cobwebs, the brain has precise organisation to the myriad of connections. These areas can be defined either by their structure, or by their function.

Structurally, there are areas in the brain that are dominated by nerve cell bodies, formed into a little cluster, called a nucleus (different from the nucleus of each cell). Then there are groups of axons bundled together, called a tract, which behave like a data cable for your computer. Nuclei process multiple sources of signal and refine them. The refined signals are sent into the appropriate tract to be transmitted to either another set of nuclei for further refinement, or to distant structures to carry out their effect. The axons of the nerve cells that make up the tracts are usually covered in a thick white material called myelin. Myelin acts like insulation on a wire, improving the speed and accuracy of the communicated signal. Parts of the brains with lots of myelinated cells are described as “white matter”. The nuclei and the cerebral cortex (the outer covering of the brain) are unmyelinated cells, and are referred to as “grey matter”.

On a functional level, the brain is divided into parts depending on what information is processed, and how it gets processed. For example, the cerebral cortex is divided into primary areas for the senses and for motor functions, secondary areas and tertiary association areas. The primary sensory areas detect specific sensations, whereas the secondary areas make sense out of the signals in the primary areas. Association areas receive and analyze signals simultaneously from multiple regions of both the motor and sensory areas, as well as from the deeper parts of the brain [2]. The frontal lobe, and specifically pre-frontal cortex, is responsible for higher brain functions such as working memory, planning, decision making, executive attention and inhibitory control [3].

Everything our senses detect is essentially deconstructed, processed then reconstructed by our brains. For example, when reading this page, the image is decoded by our retina and sent through a number of pathways to finally reach the primary visual cortex at the back of our brain. The primary visual cortex has 6 layers of nerve cells which simultaneously encode the various aspects of the image (especially colour, intensity and movement of the signals) and this information is sent to the secondary association areas that detect patterns, both basic (lines are straight, curved, angled) and complex (two diagonal intersecting lines form an ‘x’). One part of the secondary association areas in the visual cortex (the Angular Gyrus) processes these patterns further into the patterns of written words. The information on the various patterns that were discerned by the secondary association areas then get sent to the tertiary association area for the senses where those visual patterns are combined with patterns processed from other sensory areas (hearing, touch and internal body sensations) to form a complex pattern of multimodal association [2]. In the case of reading, the tertiary association area allows comprehension of the written words that were previously only recognised as words by the secondary association areas.

In the recent decades, with the widespread adoption of non-invasive methods of studying the active living brain such as PET scanning and fMRI, researchers have discovered that rather than discrete parts of the brain lighting up with a specific task, entire networks involving multiple brain regions are activated. This has lead to the paradigm of neurocognitive networks, in which the brain is made up of multiple interconnected networks that “are dynamic entities that exist and evolve on multiple temporal as well as spatial scales” and “by virtue of both their anatomical and functional architectures, as well as the dynamics manifested through these architectures, large-scale network function underlies all cognitive ability.” [4]

Emotions and feelings

Emotions are a difficult concept to define. Despite being studied as a concept for more than a century, the definition of what constitutes an emotion remains elusive. Some academics and researchers believe that the term is so ambiguous that it’s useless to science and should be discarded [5].

I’ll discuss emotions further in chapter 2, but for now, it’s easiest to think of our emotional state as the sum total of our different physiological systems, and feelings are the awareness, or the perception of our emotional state.

Different parts of the brain are responsible for the awareness of these feelings. The amygdala is often considered the seat of our fears, the anterior insula is responsible for the feeling of disgust, and the orbitofrontal and anterior cingulate cortex are involved in a broad range of different emotions [6].

Different emotional states are linked with different neurotransmitters within the brain. For example, a predisposition to anxiety is often linked to variations in the genes for serotonin transport [7] while positive and negative affect (“joy / sadness”) are linked to the dopaminergic system [8].

Memories

Memories, like thoughts, are something that we’re all familiar with in our own way.

Memory is quite complicated. For a start, there’s more than one form of memory. You’ve probably heard of short term and long term memory. Short term memory is further thought of as sensory memory and working memory. Long term memory is divided into semantic and episodic memory. Memory is also classified as either declarative memory, also called explicit memory, and nondeclarative memory, also called implicit memory.

Squire and Wixted explain, “Nondeclarative memory is neither true nor false. It is dispositional and is expressed through performance rather than recollection. These forms of memory provide for myriad unconscious ways of responding to the world. In no small part, by virtue of the unconscious status of the nondeclarative forms of memory, they create some of the mystery of human experience. Here arise the dispositions, habits, and preferences that are inaccessible to conscious recollection but that nevertheless are shaped by past events, influence our behavior and mental life, and are an important part of who we are.” [9]

On the other hand, declarative memory “is the kind of memory that is referred to when the term memory is used in everyday language. Declarative memory allows remembered material to be compared and contrasted. The stored representations are flexible, accessible to awareness, and can guide performance in a variety of contexts. Declarative memory is representational. It provides a way of modeling the external world, and it is either true or false.” [9]

Working memory is a central part of the memory model. Information from feelings, stored memories and actions all converge in working memory. The model of working memory initially proposed by Baddeley involves a central executive, “a control system of limited attentional capacity that is responsible for the manipulation of information within working memory and for controlling two subsidiary storage systems: a phonological loop and a visuospatial sketchpad.”[10] Baddeley later added a third subsidiary system, the episodic buffer, “a limited capacity store that is capable of multi-dimensional coding, and that allows the binding of information to create integrated episodes.” [10]

Working memory is known to be distinct from other longer term memories that are dependent on part of the brain called the hippocampus, because patients with severe damage to the hippocampus can remember a small amount of information for a short time, but are not able to push that information into longer term memory functions to retain that information. Information in working memory doesn’t last for any more than a few minutes [9].

So, there are many forms of memory that are important to our lives and influence our behaviour that are “inaccessible to conscious recollection”. But even declarative memory, which is accessible to thought, doesn’t actually make up the thought itself. Memories are stored representations.

When memories are formed or retrieved, the information is processed in chunks. As Byrne pointed out, “We like to think that memory is similar to taking a photograph and placing that photograph into a filing cabinet drawer to be withdrawn later (recalled) as the ‘memory’ exactly the way it was placed there originally (stored). But memory is more like taking a picture and tearing it up into small pieces and putting the pieces in different drawers. The memory is then recalled by reconstructing the memory from the individual fragments of the memory.” [11] Recalling the original memory is an inaccurate process, because sometimes these pieces of the memory are lost, faded or mixed up with another [12]. This is why what we perceive and what we recall are often two different things entirely.

Why do we have memory then, if it’s so flawed at recalling information? Because memory is less about recalling the past, and more about imagining and planning the future. As Schacter writes, “The constructive episodic simulation hypothesis states that a critical function of a constructive memory system is to make information available in a flexible manner for simulation of future events. Specifically, the hypothesis holds that past and future events draw on similar information and rely on similar underlying processes, and that the episodic memory system supports the construction of future events by extracting and recombining stored information into a simulation of a novel event. While this adaptive function allows past information to be used flexibly when simulating alternative future scenarios, the flexibility of memory may also result in vulnerability to imagination-induced memory errors, where imaginary events are confused with actual events.” [13]

References

Sukel, K. The Synapse – A Primer. 2013 [cited 2013, 28/06/2013]; Available from: http://www.dana.org/media/detail.aspx?id=31294.
Hall, J.E. and Guyton, A.C., Guyton and Hall textbook of medical physiology. 12th ed. 2011, Saunders/Elsevier, Philadelphia, Pa.:
Stuss, D.T. and Knight, R.T., Principles of frontal lobe function. 2nd ed. 2013, Oxford University Press, Oxford ; New York:
Meehan, T.P. and Bressler, S.L., Neurocognitive networks: findings, models, and theory. Neurosci Biobehav Rev, 2012. 36(10): 2232-47 doi: 10.1016/j.neubiorev.2012.08.002
Dixon, T., “Emotion”: The History of a Keyword in Crisis. Emot Rev, 2012. 4(4): 338-44 doi: 10.1177/1754073912445814
Tamietto, M. and de Gelder, B., Neural bases of the non-conscious perception of emotional signals. Nat Rev Neurosci, 2010. 11(10): 697-709 doi: 10.1038/nrn2889
Caspi, A., et al., Genetic sensitivity to the environment: the case of the serotonin transporter gene and its implications for studying complex diseases and traits. Am J Psychiatry, 2010. 167(5): 509-27 doi: 10.1176/appi.ajp.2010.09101452
Felten, A., et al., Genetically determined dopamine availability predicts disposition for depression. Brain Behav, 2011. 1(2): 109-18 doi: 10.1002/brb3.20
Squire, L.R. and Wixted, J.T., The cognitive neuroscience of human memory since H.M. Annu Rev Neurosci, 2011. 34: 259-88 doi: 10.1146/annurev-neuro-061010-113720
Repovs, G. and Baddeley, A., The multi-component model of working memory: explorations in experimental cognitive psychology. Neuroscience, 2006. 139(1): 5-21 doi: 10.1016/j.neuroscience.2005.12.061
Byrne, J.H. Learning and Memory (Section 4, Chapter 7). Neuroscience Online – an electronic textbook for the neurosciences 2013 [cited 2014, Jan 3]; Available from: http://neuroscience.uth.tmc.edu/s4/chapter07.html.
Bonn, G.B., Re-conceptualizing free will for the 21st century: acting independently with a limited role for consciousness. Front Psychol, 2013. 4: 920 doi: 10.3389/fpsyg.2013.00920
Schacter, D.L., et al., The future of memory: remembering, imagining, and the brain. Neuron, 2012. 76(4): 677-94 doi: 10.1016/j.neuron.2012.11.001

Dr Caroline Leaf and the shotgun approach

Posted on October 20, 2014 by cedwardpitt

“It has been collectively demonstrated by researchers around the world that just about every aspect of our brainpower, intelligence and control – in normal, and psychiatrically and neurologically impaired individuals – can be improved by intense, efficient, organised and appropriately direct mind training … thank you Jesus.”

Sounds impressive doesn’t it.

Unfortunately for Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist, grandstanding does not equate to authority. It’s all very well and good to publish broad, sweeping generalisations, but it’s like firing a shotgun at a cork from thirty paces. Sure, you might hit your target, but the scatter pattern of the ammunition misses more times than it hits.

If Dr Leaf wants her statement to be taken seriously, then she needs to do a couple of small things.
(1) Reference her statement. This should be fairly easy if “researchers around the world” really have demonstrated the power of mind training. To sum it up more effectively, perhaps Dr Leaf could cite a meta-analysis that proves the value of mind training.
(2) Stop confusing the mind with the brain. This is the biggest problem with her statement. The mind does not control the brain. If Dr Leaf produced any references in support of her statement, they would be along the lines of training or retraining the brain, not the mind.

It may seem trivial, because most people think the mind and the brain are the same, but they’re two distinct things. Old psychological therapies were based upon the notion that fixing your thoughts was the key to improving your mental health, but this notion is now outdated, considered part of “Western folk psychology” [1]. By using the concept of “mind” and “brain” interchangeably, Dr Leaf confuses the issue for the average person trying to come to grips with modern science.

I’d be grateful if Dr Leaf could publish some evidence to support her claim, because I’m unfamiliar with research showing that things like intelligence can be improved with brain training. Sure, there’s good evidence for the improvement in the damaged brain with specific physical exercises – it’s one of the primary tools in Rehabilitation Medicine. There is also good evidence for psychological therapies such as ACT, or Acceptance and Commitment Therapy, in improving mood amongst other things [2, 3]. Though I’ve read a recent meta-analysis of multiple studies that suggests “brain training” for working memory offers minimal benefit which is not maintained and not transferable across categories [4], which means there’s no proof that “brain training” improves intelligence.

In future posts, I hope that Dr Leaf provides something more accurate instead of grandiose shotgun statements.

References

Herbert, J.D. and Forman, E.M., The Evolution of Cognitive Behavior Therapy: The Rise of Psychological Acceptance and Mindfulness, in Acceptance and Mindfulness in Cognitive Behavior Therapy. 2011, John Wiley & Sons, Inc. p. 1-25.
Harris, R., Embracing Your Demons: an Overview of Acceptance and Commitment Therapy. Psychotherapy In Australia, 2006. 12(6): 1-8 http://www.actmindfully.com.au/upimages/Dr_Russ_Harris_-_A_Non-technical_Overview_of_ACT.pdf
Harris, R., The happiness trap : how to stop struggling and start living. 2008, Trumpeter, Boston:
Melby-Lervag, M. and Hulme, C., Is working memory training effective? A meta-analytic review. Dev Psychol, 2013. 49(2): 270-91 doi: 10.1037/a0028228

Labels – the good, the bad, and the ugly

Posted on October 19, 2014 by cedwardpitt

Yesterday, I wrote a rebuttal to Dr Caroline Leaf’s social media post, that “Psychiatric labels lock people into mental ill-health.” In my rebuttal, I suggested that psychiatric labels don’t lock anyone into mental ill-health any more than a medical diagnosis locks people into physical ill-health.

In the feedback I received, one intelligent young lady commented that, “I understand your point completely, but I took her words differently. I have often seen people who use their diagnosis as an excuse. For example, a kid gets diagnosed with Autism or ADHD, and suddenly the parents are using that as an excuse for their bad behaviour instead of teaching and helping them to deal with it. Another example, an adult is diagnosed with something mild, but uses it as an excuse to no longer care about trying to get a job or trying to get treatment and make an effort to get better”.

I certainly understand where she’s coming from. I’ve seen it too. A diagnosis is used as an excuse for someone’s avoidance, or a tool to milk every drop of sympathy from another. Giving someone a label seems to hinder some people more than help them.

Thankfully, there’s more than one side to the label story. I wanted to use today’s post to discuss the good, the bad, and the ugly side of diagnostic labels.

First, lets look at the ugly side of a diagnostic label. There will always be emotional and social connotations to every diagnosis that a person receives. Sometimes that’s sympathy, and sometimes that’s stigma. If a young woman told her friends that she had breast cancer, I’m sure that news would be met with an outpouring of care and support. If the same young woman told the same friends that she had chlamydia or genital herpes, I’d bet that most of the responses would be blaming or shaming, which is one reason why no one tells other people they’ve got chlamydia or herpes.

The same goes for mental health. The media often portrays people with mental illness as either homicidal or weak [1]. So the general response to mental health diagnoses is either fear or contempt. Even those who are neutral towards mental health often don’t understand it, so it’s difficult for those with mental health issues to receive true empathy for their plight.

Then, there is the bad side of a label. Labels can be misused, intentionally or unintentionally, for all sorts of reasons. They can also be wrongly applied. It might be that someone uses their diagnosis to draw sympathy from people, or money, or help when they don’t really need it. They might use their label as an excuse to avoid certain things they don’t like. There are innumerable ways that people can milk secondary gain from their problems.

However, appropriate diagnosis can bring many benefits. For example, correct labelling brings with it understanding and empowerment.

A diagnosis can help us understand more about ourselves, or the person with the diagnosis. That child with ADHD isn’t just being naughty, but has difficulty regulating their behaviour. That person with Asperger’s isn’t being intentionally rude, but has trouble with social cues, understanding body language, and communicating in an empathic way. A correct diagnosis also helps us understand our own strengths and weaknesses. They help us recognise what it is about ourselves that we can’t change, what we can change, and what we need to change.

Once you understand what it is you can change and what you can’t change, it empowers you to change what you can for the better, and accept and adapt to what you can’t change. You stop wasting precious strength and time fighting what you can’t change. Instead, all of the effort that would have been needlessly spent on the unchangeable can be effectively spent on improving what needs to be, and can be, changed.

In fairness, I should point out that a diagnosis isn’t always needed to make positive change. Acceptance and Commitment Therapy is a form of psychological therapy that encourages flexibility to accept those parts of our lives that are uncomfortable, whether they have a label or not, and allow our values to shape our life direction. Sometimes we can spend so much energy looking for a diagnosis that we stagnate, forgoing the forward momentum of what we value to focus on having a label for the symptoms.

But where a diagnosis can be made without undue effort, it can provide clarity to what often seems to be a jumbled mess of dysfunctional traits.

So, sure, sometimes labels can be used for the wrong things. That doesn’t mean they’re not useful or we should stop using them. There may be a stigma to a diagnosis of herpes or depression, but there are also good treatments available. The diagnosis may provide a way of changing a life of ongoing suffering to a life fulfilled.

More often than not, a good diagnosis helps bring clarity to a situation, enabling understanding, acceptance and empowerment. Rather than locking people in, a correct label usually unlocks a person’s potential to grow despite the problems they face.

References

Corrigan, P.W. and Watson, A.C., Understanding the impact of stigma on people with mental illness. World Psychiatry, 2002. 1(1): 16-20 http://www.ncbi.nlm.nih.gov/pubmed/16946807

Dr C. Edward Pitt

Faith, Hope, Love, Science.

Category Archives: Caroline Leaf

Dr Caroline Leaf and the chemistry of perceptions

Dr Caroline Leaf and the tongues trivia tall tales

Dr Caroline Leaf: Putting thought in the right place

Dr Caroline Leaf and the matter of mind over genes

Understanding Thought – Part 3

Other cognitive frameworks of thought

Dual Systems

Relational Frame Theory / Acceptance And Commitment Therapy

What is, and is not, a thought?

Brain activity

Dreams

Memories

Understanding Thought – Part 2, The Neuroscience of Thought

Neuroscience of thought

Global Workspace / Intelligent Distribution Agent Model

Neural networks involved in the neurobiology of thought?

Understanding Thought – Part 1

Dr Caroline Leaf and the shotgun approach

Labels – the good, the bad, and the ugly