Dr Justin Marley

A Brief Overview of The Cannon-Bard Thalamic Theory of Emotions: Building a Model of the Insular Cortex – Part 8

CannonBardThalamicTheoryofEmotions

In Part 7 of the series, I looked briefly at the James-Lange Theory of Emotional Regulation which states that emotions occur secondary to the physiological response to a stimulus. A contrasting theory of emotions is the Cannon-Bard theory which states that our emotional and physiological responses to a stimulus occur simultaneously. One specific variation of this theory is the Cannon-Bard Thalamic Theory of Emotions. In this theory it is assumed that the Thalamus is inhibited from sending activating signals to the Autonomic Nervous System by inhibitory signals from the Cerebral Cortex. The Theory states that an appropriate stimulus can activate the Cerebral Cortex and remove the inhibitory control on the Thalamus. Subsequently there is both cortical activity and autonomic activity – emotional and physiological responses to the stimulus. A schematic for this theory is shown in the diagram above.

There is some experimental data to support this theory which I won’t cover here. If we consider this theory it helps us to think about emotions differently. If we start to look at the Thalamus as an area which regulates emotional responses then we can examine relevant data to further explore this. For instance this small case series looks at the treatment of Tourette’s Syndrome using Deep Brain Thalamic Stimulation. In one case the researchers report a decrease in Depression but an increase in aggression. The caveat is that case series are generally good at posing hypotheses for further exploration. A case of pathological laughter subsequent to a gamma knife Thalamotomy was treated with Sertraline in this paper. By generating explicit neuroanatomical models of emotional regulation we can begin to examine the literature in a more systematic way. Even if we start off with an innaccurate model, we may after many iterations arrive at a better understanding of these phenomenon.

Insular Cortex Resources on this Site

Developing a Model of the Insular Cortex and Emotional Regulation: Part 1

Building a Model of the Insular Cortex – Part 2

Building a Model of the Insular Cortex – Part 3

Building a Model of the Insular Cortex – Part 4

Building a Model of the Insular Cortex – Part 5

Building a Model of the Insular Cortex – Part 6

Building a Model of the Insular Cortex – Part 7

What does the Insular Cortex Do Again?

Insular Cortex Infarction in Acute Middle Cerebral Artery Territory Stroke

The Insular Cortex and Neuropsychiatric Disorders

The Relationship of Blood Pressure to Subcortical Lesions

Pathobiology of Visceral Pain

Interoception and the Insular Cortex

A Case of Neurogenic T-Wave Inversion

Video Presentations on a Model of the Insular Cortex

MR Visualisations of the Insula

The Subjective Experience of Pain

How Do You Feel? Interoception: The Sense of the Physiological Condition of the Body

How Do You Feel – Now? The Anterior Insula and Human Awareness

Role of the Insular Cortex in the Modulation of Pain

The Insular Cortex and Frontotemporal Dementia

A Case of Infarct Connecting the Insular Cortex and the Heart

The Insular Cortex: Part of the Brain that Connects Smell and Taste?

Stuttered Swallowing and the Insular Cortex

YouTubing the Insular Cortex (Brodmann Areas 13, 14 and 52)

New Version of Video on Insular Cortex Uploaded

Index: There are indices for the TAWOP site here and here Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.

20 comments

  2. OK, here’s another problem. It appears that behavior is triggered, well below the cortex, in 150 ms. There is simply no time for emotional stuff, which happens in seconds, to have any influence. It looks like “higher order concepts” like emotions, choice, consciousness, decsion making etc are merely correlated and not causal with behavior.

    If emotions or any of these HOC were important to brain >behavior processes, we would find them across the animal kingdom.

    Look at LeDoux’s latest paper in Cell “Rethinking the Emotional Brain.”

    Bottom line, it look like subjective experiences are epiphenomenal – as animal ethology would suggest.

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  3. Response to first reply : The stimuli would be detected by the sensory system – visual/auditory apparatus etc. Although the ANS has a small sensory component it is for interoception. The diagram is a schematic.
    There are multiple pathways passing through the Thalamus including Basal Ganglia motor inhibitory/excitatory pathways.
    The cortex would inhibit ANS responses to Thalamic input in this model. The ANS is therefore a second order connection. The cortex played a role in the original experiments supporting this theory to the best of my understanding.

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  4. Response to second reply: Excellent – this is the whole point of the post – to stimulate debate – after all this is an open model. We can have a very quick emotional response – sudden fear for instance. I think your point is a good one though – it seems unlikely that all emotional experiences will be matched by a simultaneous physiological response.
    This is just a model – another position – which contrasts with the James-Lange theory as well as other theories of emotions. Once you start challenging it though, new insights emerge – a variation on the Hegelian Dialectic.

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  5. The timing problem seems to set the boundaries. My desktop is a ms schematic of two neurons competing to drive action. Man! It is fast!! Where there is time for any HOC’s I just don’t see it. Of course, that challenges all our naive realistic beliefs.

    Have no use for philosophy. What has philosophy ever predicted? But yes, research suggests principled argument is best way to sounds ideas. I did hear a debunking of James-Lange, can’t remember where. My sense is that LeDoux now is consistent with the most findings. DeMasio, etc. – not so much.

    The main obstacles seems to be ideological campaigns to top-down fit subjective experiences into the human brain physiology, eg a spot for empathy (an actual failed attempt.). Of course, animal brains are ignored. That’s just bad medicine/science. But predictable.

    Was at good neuroscience conf in Chicago with very smart grad students. They are walking away from cognitive, psychological, behavioral models and imaging and returning to basic physiological processes prior to anything happening “up there.”

    Another insight from a guy named Paul Cisek is that the processes is continuous and ecological — again as animal ethology tells us.

    So how may this inform clinical, practical work. Well, “Information is expensive” and what is easiest to perceive and discuss, subjective experience, probably doesn’t carry much information value.

    My read is that spending time on emotions is as much a waste of time as on “personality,” “thinking” or other natural language HOCs. Time to move back to basic physiology.

    But think of it this way. All the thousands of years of opinions, ideas, speculations, etc on brain > behavior are now obsolete. Any college kid knows more about this then the greatest minds in human history – more than Socrates, Plato, Kant, Wittgenstein, Einstein, etc.! Pretty radical.

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  6. Here’s a good example – we scan this stuff all day…

    “We conclude that oxytocin shifts the individual’s focus from self to group-serving cognition and decision-making, and that these tendencies are stronger for males with high rather than low fetal testosterone vs. estradiol exposure, and high rather than low empathic concern. Implications and avenues for future research are discussed.”

    We have no idea about “cognition and decision making” those are higher order concepts that need to be proven exist and how they work at a neuronal level, not to assume them. This contains mere ideological/belief assumptions. All we really have is behavior we label as such. Physiology is all we have — biological entities, neurons, muscles, etc acting/moving – in measurable ways.

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  7. Response to third reply: Philosophy has been essential in generating the infrastructure for science disciplines. Thomas Kuhn (https://theamazingworldofpsychiatry.wordpress.com/2012/01/19/a-review-of-the-structure-of-scientific-revolutions/) writes about the development of science not as a linear progression but rather as a paradigm shift within scientific communities. College textbooks provide a distillation of the accumulated knowledge but there is another aspect of the living science which is not captured in a distillation.

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  8. Response to fourth reply: While a higher degree of precision can be afforded when referring to basic physiological processes this does not negate conscious experience. Simply discounting our inner experiences removes an absolutely essential aspect of our lives – meaning making – without which science wouldn’t exist. The real challenge is not to discount this but to move towards a valid integration of mind/brain models https://theamazingworldofpsychiatry.wordpress.com/2013/01/17/integration-in-neuroscience-a-core-problem-part-7-three-structure-model/

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