Tag Archives: Global Workspace

Dr Caroline Leaf – Thoughts are real. So what?

Posted on by
4

Screen Shot 2015-10-05 at 12.53.02 pm

Today’s meme from Dr Leaf is one of her favourite, often repeated phrases:

“Thoughts are real and occupy mental real estate.”

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. Her entire preaching empire rests on her assumption that our thinking is the driving force of not just our mental health but also our physical health, and even physical matter!

No one’s denying that thoughts are real. The key issue is not whether thoughts are real, but what thoughts really are.

Professor Bernard J. Baars is an Affiliate Fellow at The Neurosciences Institute in La Jolla, California. He is a real cognitive neuroscientist. In the late 1980’s, Professor Baars built on Baddeley’s model of working memory by proposed the Global Workspace theory [1]. Together with Professor Stan Franklin, also a real cognitive neuroscientist (and a mathematician and computer scientist) at the University of Memphis, they took the Global Workspace theory further with 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 about ten cycles could be running per second, 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.” [3]

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, 4]. It’s the broadcasting of this portion of the information flow that renders it “conscious”.

So thought is nothing more than a broadcast of one part of a deeper flow of information. In the same way that a projection on a movie screen is a real series of images of a historical or fictional event, but not the actual event, so thoughts are a real but are just a projection of the deeper information stream within the brain.

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.

So Dr Leaf is right, thoughts are real. So what? Thoughts are just a projection, a function of the brain. They are not independent of the brain and they do not control the brain. And they definitely don’t control physical matter.

In posting things like todays meme, Dr Leaf is proving just how far her assumptions are from the work of real cognitive neuroscientists, while misdirecting her audience, duping them into believing that her tenuous speculation is scientific fact.

References

[1]        Baars BJ. A cognitive theory of consciousness. Cambridge England ; New York: Cambridge University Press, 1988.
[2]        Baars BJ, Franklin S. How conscious experience and working memory interact. Trends in cognitive sciences 2003 Apr;7(4):166-72.
[3]        Franklin S, Strain S, McCall R, Baars B. Conceptual Commitments of the LIDA Model of Cognition. Journal of Artificial General Intelligence 2013;4(2):1-22.
[4]        Baars BJ. Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research 2005;150:45-53.

Dr Caroline Leaf: Putting thought in the right place

Posted on by
4

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].

CAP v2.1.2
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

  1. Leaf, C., Who Switched Off My Brain? Controlling toxic thoughts and emotions. 2nd ed. 2009, Inprov, Ltd, Southlake, TX, USA:
  2. Leaf, C.M., Switch On Your Brain : The Key to Peak Happiness, Thinking, and Health. 2013, Baker Books, Grand Rapids, Michigan:
  3. 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
  4. Oxford Dictionary of English – 3rd Edition, 2010, Oxford University Press: Oxford, UK.
  5. 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
  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.
  7. 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
  8. 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
  9. Felten, A., et al., Genetically determined dopamine availability predicts disposition for depression. Brain Behav, 2011. 1(2): 109-18 doi: 10.1002/brb3.20
  10. 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
  11. 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
  12. 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
  13. Watkins, A. Being brilliant every single day – Part 1. 2012 [cited 2 March 2012]; Available from: http://www.youtube.com/watch?v=q06YIWCR2Js.
  14. Dixon, T., “Emotion”: The History of a Keyword in Crisis. Emot Rev, 2012. 4(4): 338-44 doi: 10.1177/1754073912445814
  15. Elliott, R., Executive functions and their disorders Imaging in clinical neuroscience. British Medical Bulletin, 2003. 65(1): 49-59
  16. 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
  17. 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
  18. Baars, B.J., Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research, 2005. 150: 45-53
  19. 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
  20. 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
  21. 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.

Understanding Thought – Part 3

Posted on by
Reply

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

Posted on by
1

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