Monthly Archives: October 2014

Understanding Thought – Part 3

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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.

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 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

  1. 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
  2. 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
  3. 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
  4. 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
  5. 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
  6. 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
  7. Shakespeare, W., Hamlet, Act II, Scene 2.
  8. 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
  9. Franklin, S., et al., Conceptual Commitments of the LIDA Model of Cognition. Journal of Artificial General Intelligence, 2013. 4(2): 1-22
  10. 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
  11. 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
  12. 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

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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.

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

  1. Baars, B.J., A cognitive theory of consciousness. 1988, Cambridge University Press, Cambridge England ; New York:
  2. 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
  3. Madl, T., et al., The timing of the cognitive cycle. PLoS One, 2011. 6(4): e14803 doi: 10.1371/journal.pone.0014803
  4. Franklin, S., et al., Conceptual Commitments of the LIDA Model of Cognition. Journal of Artificial General Intelligence, 2013. 4(2): 1-22
  5. Baars, B.J., Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research, 2005. 150: 45-53
  6. 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
  7. 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
  8. 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
  9. 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
  10. 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.
  11. Baird, B., et al., Inspired by distraction: mind wandering facilitates creative incubation. Psychol Sci, 2012. 23(10): 1117-22 doi: 10.1177/0956797612446024
  12. 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
  13. 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.

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“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!”

  1. “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.

  1. “… 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,

  1. “… 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

  1. 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

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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.

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 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

  1. Sukel, K. The Synapse – A Primer. 2013 [cited 2013, 28/06/2013]; Available from: http://www.dana.org/media/detail.aspx?id=31294.
  2. Hall, J.E. and Guyton, A.C., Guyton and Hall textbook of medical physiology. 12th ed. 2011, Saunders/Elsevier, Philadelphia, Pa.:
  3. Stuss, D.T. and Knight, R.T., Principles of frontal lobe function. 2nd ed. 2013, Oxford University Press, Oxford ; New York:
  4. 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
  5. Dixon, T., “Emotion”: The History of a Keyword in Crisis. Emot Rev, 2012. 4(4): 338-44 doi: 10.1177/1754073912445814
  6. 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
  7. 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
  8. Felten, A., et al., Genetically determined dopamine availability predicts disposition for depression. Brain Behav, 2011. 1(2): 109-18 doi: 10.1002/brb3.20
  9. 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
  10. 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
  11. 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.
  12. 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
  13. 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

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“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

  1. 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.
  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
  3. Harris, R., The happiness trap : how to stop struggling and start living. 2008, Trumpeter, Boston:
  4. 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

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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

  1. 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 Caroline Leaf – Exacerbating the Stigma of Mental Illness

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It was late in the afternoon, you know, that time when the caffeine level has hit critical and the only way you can concentrate on the rest of the day is the promise you’ll be going home soon.

The person sitting in front of me was a new patient, a professional young woman in her late 20’s, of Pakistani descent. She wasn’t keen to discuss her problems, but she didn’t know what else to do. After talking to her for a few minutes, it was fairly obvious that she was suffering from Generalised Anxiety Disorder, and I literally mean suffering. She was always fearful but without any reason to be so. She couldn’t eat, she couldn’t sleep, her heart raced all the time.

I was actually really worried for her. She let me do some basic tests to rule out any physical cause that was contributing to her symptoms, but that was as far as she let me help her. Despite talking at length about her diagnosis, she could not accept the fact that she had a psychiatric condition, and did not accept any treatment for it. She chose not to follow up with me either. I only saw her twice.

Perhaps it was fear for her job, social isolation, or a cultural factor. Perhaps it was the anxiety itself. Whatever the reason, despite having severe ongoing symptoms, she could not accept that she was mentally ill. She was a victim twice over, suffering from both mental illness, and its stigma.

Unfortunately, this young lady is not an isolated case. Stigma follows mental illness like a shadow, an extra layer of unnecessary suffering, delaying proper diagnosis and treatment of diseases that respond best to early intervention.

What contributes to the stigma of mental illness? Fundamentally, the stigma of mental illness is based on ignorance. Ignorance breeds stereotypes, stereotypes give rise to prejudice, and prejudice results in discrimination. This ignorance usually takes three main forms; people with mental illness are homicidal maniacs who need to be feared; they have childlike perceptions of the world that should be marveled; or they are responsible for their illness because they have weak character [1].

Poor information from people who claim to be experts doesn’t help either. For example, on her social media feed today, Dr Caroline Leaf said, “Psychiatric labels lock people into mental ill-health; recognizing the mind can lead us into trouble and that our mind is powerful enough to lead us out frees us! 2 Timothy1:7 Teaching on mental health @TrinaEJenkins 1st Baptist Glenardin.”

Dr Caroline Leaf is a communication pathologist and self-titled cognitive neuroscientist. It’s disturbing enough that Dr Leaf, who did not train in cognitive neuroscience, medicine or psychology, can stand up in front of people and lecture as an “expert” in mental health. It’s even more disturbing when her views on mental health are antiquated and inane.

Today’s post, for example. Suggesting that psychiatric labels lock people in to mental ill-health is like saying that a medical diagnosis locks them into physical ill-health. It’s a nonsense. Does diagnosing someone with cancer lock them into cancer? It’s the opposite, isn’t it? Once the correct diagnosis is made, a person with cancer can receive the correct treatment. Failing to label the symptoms correctly simply allows the disease to continue unabated.

Mental illness is no different. A correct label opens the door to the correct treatment. Avoiding a label only results in an untreated illness, and more unnecessary suffering.

Dr Leaf’s suggestion that psychiatric labels lock people in to their illness is born out of a misguided belief about the power of words over our thoughts and our health in general, an echo of the pseudo-science of neuro-linguistic programming.

The second part of her post, that “recognizing the mind can lead us into trouble and that our mind is powerful enough to lead us out frees us” is also baseless. Her assumptions, that thought is the main driving force that controls our lives, and that fixing our thought patterns fixes our physical and psychological health, are fundamental to all of her teaching. I won’t go into it again here, but further information on how Dr Leaf’s theory of toxic thinking contradicts basic neuroscience can be found in a number of my blogs, and in the second half of my book [2].

I’ve also written on 2 Timothy 1:7 before, another of Dr Leaf’s favourite scriptures, a verse whose meaning has nothing to do with mental health, but seized upon by Dr Leaf because one English translation of the original Greek uses the words “a sound mind”.

So Dr Leaf believes that labelling someone as having a mental illness will lock them into that illness, an outdated, unscientific and purely illogical notion that is only going to increase the stigma of mental illness. If I were @TrinaEJenkins and the good parishioners of 1st Baptist Glenardin, I would be asking for my money back.

With due respect, and in all seriousness, the stigma of mental illness is already disproportionate. Mental illness can cause insurmountable suffering, and sometimes death, to those who are afflicted by it. The Christian church does not need misinformation compounding the suffering for those affected by poor mental health. Dr Leaf should not be lecturing anyone on mental health until she has been properly credentialed.

References

  1. 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
  2. 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

Dr Caroline Leaf and the myth of the myth of multitasking

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Can you successfully multitask?

According to Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist, multi-tasking is a myth.

Actually, Dr Leaf isn’t completely wrong. Her factoid is so vague that there may be some truth in it somewhere. The problem with teaching via vague factoid is that no one can apply anything from it. If we were to take Dr Leaf’s statement as a specific teaching or advice, then we would be misled.

Why? Because it all comes down to how you define ‘multi-tasking’.

I have a couple of patients in a nursing home, two old ladies who sit on a balcony in the sun, knitting and talking at the same time. Isn’t that multi-tasking? Think of what you do every day. How often are you doing something menial while doing something requiring a bit more attention? How often do you have a conversation with your passenger while your driving? Isn’t that multi-tasking? When you get up in the morning and you are able to make a cup of tea and some breakfast at the same time, read some of the paper or your e-mails while you’re eating your breakfast at the same time, etc. Isn’t that multi-tasking?

We multi-task all the time. If we had to do everything in a linear, sequential fashion, we would never get anything done. We are able to multi-task because routine tasks have become largely habitualised by our brains and don’t need lots of processing power to complete. Hence why we can do something as complex a driving a car while still talking to our passenger or listening to music. Certain occupations, such as air-traffic control, involve high levels of multi-tasking [1].

When a task is new and/or complicated, our brains need to utilise our resources of attention to properly process the information required by the task. There is only so much that our working memory can handle. Our working memory uses tricks to handle larger amounts of information through a process called “chunking” [2] but there is still a finite limit. Performing two or more cognitively demanding tasks at the same time is difficult, and the brain can often cope by shifting tasks, although there is always a price to pay for this [3].

So it is true that there are some tasks that require more of the cognitive capacity of the brain to process. The higher the cognitive load, the more capacity needed, and the less likely that the brain will be able to multi-task with it. Thus, it’s reasonable to suggest that we can’t multi-task all of the time with every task we have to perform (although the more we do a task, the more habitual it becomes, thus reducing the cognitive load of the task, and increasing our ability to multi-task it).

However it’s misleading to say that we can’t multi-task at all. It’s a myth that multi-tasking is a myth. Dr Leaf’s comment that, “Paying attention to one task at a time is the correct way”, isn’t a summary of the neuroscience of attention, but a subjective statement based on her grandiose pretension. There is no objective evidence that “one task at a time” offers generally applicable benefit.

So don’t be afraid of multi-tasking. Just know your limits.

References

  1. Nelson, J.T., et al., Enhancing vigilance in operators with prefrontal cortex transcranial direct current stimulation (tDCS). Neuroimage, 2014. 85 Pt 3: 909-17 doi: 10.1016/j.neuroimage.2012.11.061
  2. 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
  3. Monsell, S., Task switching. Trends in cognitive sciences, 2003. 7(3): 134-40

Dr Caroline Leaf and the cart-before-the-horse conundrum

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A chaotic mind filled with thoughts of anxiety, worry, etc. sends out the wrong signal right down to the level of our DNA

So says Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist.

Her Facebook factoids have varied in their quality lately, ranging from the almost reasonable, down to the outright ridiculous. Today’s contribution rates an 8.5 out of 10 on the pseudoscience scale.

The reason why it rates so high is for the same reason why many of her factoids, and indeed nearly all her teaching, rates the same: Dr Leaf has the relationship between the brain and the mind back to front.  Dr Leaf squarely puts the proverbial cart before the horse.

One would think if you were going to claim to be a cognitive neuroscientist, you would at least get the basic facts right. But Dr Leaf’s teaching, from her first book through to her last, is based on this idea that it’s the mind that is in control of the brain, hence why she thinks that thoughts can be so toxic.

Dr Leaf’s entire teaching heavily rests on her fallacious assumption that the mind is in control of the brain. Thoughts are only important if the mind controls the brain. Toxic thoughts can only affect our health if the mind controls the body. Controlling toxic thoughts is only worthwhile if our mind can influence our brain and body in positive or negative ways.

The problem for Dr Leaf is that there is no credible scientific evidence that the mind controls the brain. The only evidence she does tend to proffer is based on the work of other pseudoscientists, or she misinterprets or misquotes real scientific data to fit her erroneous working theory. For example, Dr Leaf refers to a paper titled, “Local and nonlocal effects of coherent heart frequencies on conformational changes of DNA” [1]. She says that this paper is, “An ingenuous experiment set up by the HeartMath Foundation (which) determined that genuine positive emotion, as reflected by a measure called ‘heart rate variability’, directed with intentionality towards someone actually changed the way the double helix DNA strand coils and uncoils. And this goes for both positive and negative emotions and intentions.” [2: p111] Actually, the experiment was based on faulty assumptions, and so full of flaws in their methodology and analysis, that it could show nothing at all [3]. All it could prove was that Dr Leaf was so desperate to grasp hold of anything that seemed to support her theory that she was willing to use a twenty-year-old study from a group of pseudoscientists that also believe in occult practices like ESP and telekinesis (http://psychotronics.org).

The concept that we have a soul that’s separate to, and controls our brain, is called dualism. Modern science gave up on dualism a long time ago. While psychological sciences have been slower to give up on the idea of our thoughts as influential, no credible scientist still holds on to the idea that we have an ethereal force that controls our biology. Dualism is untenable both scientifically and philosophically [4].

The reality is the exact opposite to what Dr Leaf teaches. Our brain is responsible for all of the functions that are traditionally associated with the mind/soul/spirit. For more in depth information, please see my essay: Dr Caroline Leaf, Dualism, and the Triune Being Hypothesis. Therefore, a “chaotic mind filled with thoughts of anxiety, worry, etc” doesn’t send signals down to our DNA. It’s our DNA and the many steps in it’s expression, and the interaction of our biology and our environment, that then causes our minds to be worried, anxious, chaotic etc.

Dr Leaf is welcome to hold any view she likes, but she cannot claim to be a cognitive neuroscientist while holding a view that is directly contradicted by actual cognitive neuroscience. Nor should she be welcome to speak as an expert when she clearly is not one.

For the sake of her audiences and the Christian church as a whole, Dr Leaf needs to revise her teaching and bring it into line with the facts established by real cognitive neuroscientists.

References

  1. Rein, G. and McCraty, R. Local and nonlocal effects of coherent heart frequencies on conformational changes of DNA. in Proc. Joint USPA/IAPR Psychotronics Conf., Milwaukee, WI. 1993.
  2. Leaf, C.M., Switch On Your Brain : The Key to Peak Happiness, Thinking, and Health. 2013, Baker Books, Grand Rapids, Michigan:
  3. 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
  4. Bunge, M., The Mind-Body Problem, in Matter and Mind. 2010, Springer Netherlands. p. 143-57.

Dr Caroline Leaf and the Two Rights Principle

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They say that two wrongs don’t make a right. And as it turns out, two rights don’t always make a right either.

Dr Caroline Leaf is a communication pathologist and a self-titled neuroscientist. Her last social media post declared, “The power of renewing the mind! Romans 12:2 We have the power to restrengthen, recover, and renormalize our brain even when it has suffered major trauma.”

Each part of her post is technically correct, with a few qualifications.

As Christians, we always accept that scripture is infallible, the inspired word of God. The interpretation of that scripture is not so infallible. Dr Leaf often quotes Romans 12:2, “And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.”

When Paul wrote this scripture, what did he mean when he used the word for mind? Well, I guess I can’t speak for the Apostle Paul, but I can say that the Greek word that’s translated “mind” in this verse is “nous”. In modern times we would use this word for ‘brain’ or ‘head’, especially those with a British influence in their upbringing (“use your nous” = “use your brain”). The Greek word means,
“I. the mind, comprising alike the faculties of perceiving and understanding and those of feeling, judging, determining
a. the intellectual faculty, the understanding
b. reason in the narrower sense, as the capacity for spiritual truth, the higher powers of the soul, the faculty of perceiving divine things, of recognising goodness and of hating evil
c. the power of considering and judging soberly, calmly and impartially
d. a particular mode of thinking and judging, i.e. thoughts, feelings, purposes, desires.”
(https://www.blueletterbible.org/lang/lexicon/lexicon.cfm?Strongs=G3563&t=KJV)

Hmmm … which one did Paul really mean? Did he mean just our thoughts, all of our mental faculties, or specifically to the perception of the divine? Dr Leaf never really says, although there’s a big difference between perceiving and understanding in general, and the specific capacity for spiritual truth. So Dr Leaf’s interpretation of Romans 12:2 might be correct, depending.

The other half of her post is also true, but in the most vague sense. “We have the power to restrengthen, recover, and renormalize our brain even when it has suffered major trauma” is technically true … the brain can recover from significant trauma. It does this through neuroplasticity, broadly defined as “the ability of the nervous system to modify its structural and functional organization.” (http://emedicine.medscape.com/article/324386-overview#aw2aab6b4) Neuroplasticity is a property inherent to the nervous system of every animal that has a nervous system; humans are not unique in this regard. Given the massive scale of the human nervous system (0.15 quadrillion, or 150,000,000,000,000 synapses throughout the average brain [1]), then there is massive scope for neuroplasticity-mediated regeneration, though it’s not unlimited. Neuroscience is only just starting to unlock the incredible depth of the science of our neural synapses [2], the foundation of neuroplasticity.

However, just because her two statements are separately correct in some vague sense, does not make the combination of the two more correct. If anything, combining them results in a non-sequitur type of false argument – the two separate statements don’t support each other in a logical way. A bit like saying, “My cat has four legs. A cow has four legs, therefore a cow is a cat”. Our ability to “restrengthen, recover, and renormalize our brain” is a capacity built into our nervous system that has nothing to do with “renewing our minds” in the scriptural sense. They only seem similar in the fuzziest of ways because they share a single common element, but otherwise, they really aren’t the same process.

Dr Leaf may appear to be unlocking the hidden mysteries of scripture and science, but just because her statements are vaguely true or vaguely similar doesn’t mean they explain anything … something to be aware of when reviewing Dr Leaf’s teaching.

References

  1. Sukel, K. The Synapse – A Primer. 2013 [cited 2013, 28/06/2013]; Available from: http://www.dana.org/media/detail.aspx?id=31294.
  2. Bliss, T.V., et al., Synaptic plasticity in health and disease: introduction and overview. Philos Trans R Soc Lond B Biol Sci, 2014. 369(1633): 20130129 doi: 10.1098/rstb.2013.0129