Cognition and Emotion are not Separate

This review by Luiz Pessoa in Nature Neuroscience Reviews has to be the most intelligent things I have read in a long time. He argues that the notion that cognition and emotion are separable modules -- a notion that permeates the popular impression of the brain in our society (and more than a few scientific discussion) -- is fundamentally wrong:

In this Perspective I will make a case for the notion, based on current knowledge of brain function and connectivity, that parcelling the brain into cognitive and affective regions is inherently problematic, and ultimately untenable for at least three reasons: first, brain regions viewed as 'affective' are also involved in cognition; second, brain regions viewed as 'cognitive' are also involved in emotion; and critically, third, cognition and emotion are integrated in the brain. In the past two decades, several researchers have emphasized that emotion and cognition systems interact in important ways. Here, I will argue that there are no truly separate systems for emotion and cognition because complex cognitive-emotional behaviour emerges from the rich, dynamic interactions between brain networks. Indeed, I propose that emotion and cognition not only strongly interact in the brain, but that they are often integrated so that they jointly contribute to behaviour. Moreover, I propose that emotion and cognition are only minimally decomposable in the brain, and that the neural basis of emotion and cognition should be viewed as strongly non-modular. (Citations removed. Emphasis mine.)

Here are some choice facts he brings up to convince you that cognitive and emotional systems are not separate:

  • Emotion has usually been associated with the subcortical limbic system -- the amygdala, ventral striatum and hypothalamus -- but affective processing of reward also takes places outside the limbic system such as in the orbitofrontal cortex. Likewise parts of the limbic system such as the hippocampus are not thought to deal with affective processing.
  • The area most associated with emotion -- the amygdala -- also modulates sensory information by focusing attention on affect-laden stimuli. It also mediates some types of associative learning such as fear conditioning.
  • The activity in the amygdala closely mirrors that of cortical structures associated with cognition: "amygdala responses appear to be closely linked to perception, and are not simply predicted by the physical characteristics of the stimulus."
  • Cognitive and affective information are integrated at the level of the prefrontal cortex -- the region most associated with cognitive and executive functions. Prefrontal dysfunction has been noted in many affective disorders such as depression.
  • Anatomy has been used to dissociate cognitive and emotional processing, but a thorough examination of brain connectivity suggests that nearly all regions in the brain are highly interconnected. In addition, comparison the pattern of connectivity between the amygdala and the prefrontal cortex -- highly interconnected and distant from the sensory periphery -- shows high similarity.

He goes on to argue that the notion that there are affective and cognitive areas in the brain misunderstands brain organization. The brain is not organized in regions; it is organized in systems that perform sets of calculations. Each region may perform a different set of calculations in different contexts. He puts this more elegantly that I can:

The above considerations suggest that, in the vast majority of cases, the one-to-one mapping framework, and simple extensions thereof, describe the underlying structure very poorly. In fact, both degeneracy (many-to-one mappings, that is, multiple areas are capable of performing the same function) and pluripotentiality (one-to-many mappings) occur. In particular, degeneracy has recently received much attention as understanding this issue is central to the interpretation of the impact of focal brain damage on brain function. Having said that, it is important to note that lesions of specific brain regions, even highly connected ones, appear at times to lead to relatively specific behavioural deficits. For instance, lesions of the lateral/basolateral amygdala have been suggested to be necessary for the acquisition and expression of conditioned fear.

...

We end this section by recasting our discussion in terms of 'decomposable' and 'nondecomposable' systems. On the one hand, a decomposable system is one in which each subsystem operates according to its own intrinsic principles, independently of the others (that is, it is highly modular). On the other hand, a nondecomposable system is one in which the connectivity and inter-relatedness of the components is such that they are no longer clearly separable. I here advance the working hypothesis that emotion and cognition are only minimally decomposable. In other words, the neural basis of emotion and cognition should be viewed as governed less by properties that are intrinsic to specific sites and more by interactions among multiple brain regions. (Emphasis mine. Citations removed.)

In this view as I understand it, the function of emotion is to assign value and salience to stimuli and responses -- in essence, to guide cognition by incorporating goals and reward. As a consequence, cognition cannot take place in the absence of affective processing. To what end would such processing be directed?

Thus, Pascal's dichotomy between the heart and the reason -- "The heart has its reasons of which reason knows nothing." -- doesn't follow from what we know about the brain.

If you have access to this review, I highly recommend it. I think Pessoa is spot-on.

More like this

Although much progress has been made since neurologist Richard Restack called the brain one of science's last frontiers, the functions of some brain areas remain mysterious. Foremost among these is prefrontal cortex (PFC), a region that is much reduced in size in most other primates, is among the…
What is the deal with the stories showing brain lesions that end addiction? First, there was this one. Then, today in Nature there was another one: Strokes often change a person's character, depending on where the damage hits. Some may become more impulsive, others depressed. Now researchers have…
As described in yesterday's post, many theories have been proposed on the possible functional organization of prefrontal cortex (PFC). Although it's clear that this region plays a large role in human intelligence, it is unclear exactly "how" it does so. Nonetheless at least some general…
When I started this blog back in '06, new hypotheses were appearing on a possible functional architecture of the lateral prefrontal cortex - a recently-evolved brain area implicated in high-level cognitive functions like planning, analogical reasoning, and cognitive control. Since then, these…

It's more complex than that. Cortical and subcortical activation are mutually opposed, and people who are emotionally aroused have a great deal of difficulty thinking rationally.

The frontal lobes act as mediators between our most basic responses and our abstract concepts; damaging them can lead to profound impairments in our ability to respond to complex stimuli.

But you're lumping all sorts of divergent things together under the label "emotion", and that is simply unjustifiable. Our neurons function on a simple stimulus-response level, but that doesn't mean that our reflexes are always compatible with directed action.

By Caledonian (not verified) on 24 Jan 2008 #permalink

Cortical and subcortical activation are mutually opposed, and people who are emotionally aroused have a great deal of difficulty thinking rationally.

The first part of that statement isn't accurate. In some cases they are "opposed" in other cases they aren't. For example, striatal function is permissive for cortically initiated motion signals, but it also is involved in movement selection.

A more accurate statement would be to say that they are linked in the same system -- which is one of the arguments he makes.

The second statement is prove of what I was saying. If arousal modifies your ability to think, then that suggests that arousal is part of the system for thinking.

The frontal lobes act as mediators between our most basic responses and our abstract concepts; damaging them can lead to profound impairments in our ability to respond to complex stimuli.

The first part is essentially correct, but it is limited in scope. What you are referencing, I think, is the impulse inhibition theory of prefrontal function. However, we know now that the prefrontal cortex does considerably more than just behavioral inhibition.

This is highlighted by the complex presentation of prefrontal lesions. It is true that people with prefrontal lesions have problems with behavioral inhibition but they also have elaborate and various changes in their ability to make decisions and -- important in this case -- regulate their emotions.

But you're lumping all sorts of divergent things together under the label "emotion", and that is simply unjustifiable. Our neurons function on a simple stimulus-response level, but that doesn't mean that our reflexes are always compatible with directed action.

I am using a neuroscientific definition of emotion which I admit is a bit fuzzy. We don't tend to define emotion in terms of "sad" and "happy." We define it in terms of the way it modifies behavior. The animal desires the food because he is hungry. He acts accordingly. This is not to suggest that neuroscientists deny internal states; that isn't true. However, we don't view them in terms of abstractions.

The second sentence, I don't think I understand what you are saying. One, not all neurons are unidirectional in the snese that you are implying, and two neural networks in higher organisms are organized to have more complex responses than just reflexes. What do you mean by directed action?

From my perspective (did my thesis on the Amygdala-Orbitofrontal system) he's basically kicking in open doors here. Emotion is part of cognition, that is trivially true, just like perception is part of cognition, or like any other subset of functionality is part of cognition. But of course - as with perception - just because it is tightly coupled to other systems doesn't mean we can't fruitfully study that subsystem separately as well.

One thing that people seem to do (like Caledonian, above) is mistakenly conflate "emotion" with "feelings". Amygdala and other neural substrates are about emotion - affective evaluation - and they may indirectly give rise to feelings in humans and perhaps some other mammals. But they aren't feelings and should never be viewed as such.

I think that is a fair comment, Janne. More generally, I think that most people in this field abandoned the concept of assigning function to regions long ago.

However, I wanted to post this, though, because the lay public hasn't it seems absorbed this notion. So even if he is beating a dead horse, I think it is still a good review.

What you are referencing, I think, is the impulse inhibition theory of prefrontal function.

No. We've known for decades that the prefrontal lobes are also associated with linking abstract states with motivational drives.

If arousal modifies your ability to think, then that suggests that arousal is part of the system for thinking.

No. Arousal impairs the capacity for higher-order thought. It exists in tension with the system for thought. By your reasoning, pouring water into your computer suggests that water is part of the electronic system for data processing.

By Caledonian (not verified) on 25 Jan 2008 #permalink

Hi Jake, Lay public here. Aside from the spatial organization questions which I leave to others, I believe that emotion controls all behavior at the most fundamental level. To risk a circular argument, we (and all animals) only do what we want to do at that moment. Wanting, is an emotion.

I've been reading LeDoux and Damasio (and a few others) as carefully as I could for the last few years and have sort of come to a similar place (to the author). Similar in that I also see a far more fundamental role for emotion in behavior control.

I'd go as far as to say that direct cognitive control of behavior is a myth. Here are a few reasons.

Most animals have little or no cognitive ability. (There are different definitions for cognition.) But they do just fine choosing and executing behaviors from their repertoires.

As for humans, infants exhibit all kinds of behavior well before the have any cognitive abilities - even some before mylenation. This indicates a supportive role for cognition, not administrative like most assume. Certainly it would seem problematic to explain how the behavior control system that has evolved for hundreds of millions of years in all higher animals - would at some point in human development, give way and turn its behavior control function over to this newly evolved cognitive system.

Animal behavior is too complex for cognitive control. Cognition is sequential, one thought at a time. Even the simplest animals must multi task continuously just to survive. Even something as simple as jogging requires constant adjustments to balance, avoiding obstacles in the path, shorter strides on the uphill, etc. - all things we do simultaneously and effortlessly without thinking. Adult humans spend relatively little of their cognitive resources on behavior control. Driving down the freeway you can control your speed, location in the lane, dim your lights etc. - all while your cognitive brain is carrying on a conversation with your passenger or otherwise occupied.

Many human behaviors are actually degraded by too much cognition. As a musician I know my playing suffers when I try to think about what I'm doing. The best way to perform well is to listen to my output and try to feel the effect - and then try to guide it by tuning for the feeling I want. I can't describe it because it's not cognitive but if I start thinking about what my fingers are doing - the music disappears.

I think cognition (reason) is a support system that is called into action by emotional signals noting an exception or novel problem - like, red lights ahead, think I'll move toward the next exit. And when it provides some advice like that - it is tagged with an emotion (Damasio) that allows it to compete or augment the many other emotion signals from various emotion producing systems that are constantly arising from our filtered perceptions. These are then integrated - probably in multiple passes - to produce behavior output.

And that really makes sense. Reason can be spectacularly helpful - but that's the exception. Our thinking often produces wrong results, it is very subject to emotional bias and sometimes there just isn't enough data. Our ego may like to think it is in control of our behavior - but it's just along for the ride. Or cognition is most often called on to justify our behavior (which feels good) - not direct it. And that's how most of us use our brains - at least for any important problems (problems that we emotionally sense could affect our survival). For unimportant problems, like doing a crossword puzzle or typing this comment - the intellect pretty much gets free reign - because there are few opposing emotions present.

So, cognition is just a support system, that all animals have a tiny bit of and we have a lot of. But I propose that it is called into action by emotion signals - and it delivers it's advice in the form of a "confidence / appropriateness" tag (an emotion signal) that will compete with other emotion signals (tags from other behavior candidates) to determine if we will follow that advice.

Anyway, I've been lurking a while and thought I'd throw some of my ideas into the hopper. Thanks for doing this blog. I learn a lot from reading yours and many of the other Science Blogs.

Caledonian: "No. Arousal impairs the capacity for higher-order thought. It exists in tension with the system for thought."

I'd say it exists not in tension, but as the controlling agent over the system for thought. When we face a serious survival challenge we often do not have time to sort out the logic. We need to act instinctively and immediately. Sometimes that can be fatal - but overall I think evolution has determined that fast instinctive reactions are more effective on average than reasoning in those situations that arouse us the most - and has designed our brains accordingly.

I'd say it exists not in tension, but as the controlling agent over the system for thought.

That isn't an unreasonable hypothesis. However, we know that it's a two-way relationship: the 'higher' cortical functions inhibit the subcortical and vice versa.

Our ability to reason is a relatively recent development, and is easily overwhelmed by the much older and more powerful sets of priorities we call emotions or moods. These are distinct from our motivations and preferences, which are even more primitive, and thus do not directly compete with the higher functions for dominance.

By Caledonian (not verified) on 26 Jan 2008 #permalink

Caledonia, Thanks for getting back. I've been busy.

Let me ask you this: You say, "That isn't an unreasonable hypothesis. However, we know that it's a two-way relationship: the 'higher' cortical functions inhibit the subcortical and vice versa."

From my reading I am aware of brain scans that show increased blood flow to both cortical and sub-cortical regions during various behavior related events - such as amygdala / hypothalamus transactions during states of danger or aggression.

How could you know the difference between a two way (equal) relationship as you suggest - and a back and forth mediated by the sub-cortical regions - as I suggest?

BTW - I use "emotion" to cover all behavior associated processing that is not cognitive processing. The distinctions between motivations, preferences, moods, dispositions, predispositions, etc. I find to have ambiguous and contradictory definitions depending on which text you consult. I believe those all can and do provide emotion signals to the behavior choice mechanism in the brain - that are used to select behavior.

I also believe that similar signals come from other areas like our pre-frontal areas where social emotions originate, from our instincts, from emotion tags associated with memories of past events and beliefs, etc.

For my purposes, I classify those all as instances of what I call emotion - which I define as any non-cognitive (affective) neural process that (hypothetically) causes behavior choice and execution.

Thanks

BTW - I use "emotion" to cover all behavior associated processing that is not cognitive processing.

Yes. I believe this is the crux of our disagreement - I strongly suspect that lumping everything together into a single concept is a mistake, and that there are meaningful distinctions to be made between the passions and the preferences.

Rationality requires a relative inner calm to exist. Perturbations of the passions disrupt the delicate balance necessary for clear thought.

By Caledonian (not verified) on 27 Jan 2008 #permalink

Caledonian: "Rationality requires a relative inner calm to exist. Perturbations of the passions disrupt the delicate balance necessary for clear thought."

So, when the passions are not disrupting the balance, then rationality takes control of the behavior choice mechanism? But when passions are running strong, the passions take control of it?

If I have that right, do you think this a unique design for humans?

Without passion, rationality can function. But it doesn't necessarily do so. Otherwise, yes.

do you think this a unique design for humans?

It's not clear that any other creatures on Earth are capable of rational thought even to the degree that humans are. They *might*, and if so, I expect they would show similar patterns.

By Caledonian (not verified) on 27 Jan 2008 #permalink

However, I wanted to post this, though, because the lay public hasn't it seems absorbed this notion. So even if he is beating a dead horse, I think it is still a good review

oktay usta

It is a good site for healt (best food cooking)
I advice everybody

By oktay usta (not verified) on 07 Jul 2008 #permalink

That isn't an unreasonable hypothesis. However, we know that it's a two-way relationship: the 'higher' cortical functions inhibit the subcortical and vice versa.

Our ability to reason is a relatively recent development, and is easily overwhelmed by the much older and more powerful sets of priorities we call emotions or moods. These are distinct from our motivations and preferences, which are even more primitive, and thus do not directly compete with the higher functions for dominance..

I think that is a fair comment, Janne. More generally, I think that most people in this field abandoned the concept of assigning function to regions long ago.

However, I wanted to post this, though, because the lay public hasn't it seems absorbed this notion. So even if he is beating a dead horse, I think it is still a good review.

However, I wanted to post this, though, because the lay public hasn't it seems absorbed this notion. So even if he is beating a dead horse, I think it is still a good review

My blog has opened so many doors for me and has helped me land quite a few jobs. By being immersed in writing and showing initiative, having a blog has been a great platform and portfolio. And I would recommend to anyone looking to start or build a portfolio to have a blog.

Links building stuff are the most effective eCommerce method. I claim that submit rss feeds service can really aid your site and your contents. Your web traffic will become well optimized.