Rene Descartes held that the human mind was separate from bodily processes.  Dr. Antonio R. Damasio disagreed, as set forth in Descartes’ Error: Emotion, Reason and the Human Brain (1994). In this book, Damasio introduced the cases of Phineas Gage (long dead) and “Elliot” (a living patient), who both suffered brain damage to the ventromedial prefrontal area of their brains. 

Gage’s brain damage occurred when a metal tamping rod was accidentally shot through his brain during a blasting operation (he recovered and lived many years).  Elliot’s damage occurred as a result of a brain tumor. They were both left with high level intellectual functioning but little ability to experience emotion. 

[Gage] seemed to be like a child, with no stable sense of what was important and what was not. He was fitful, intemperate, obscene. It was as if he didn’t care about one thing more than another. He seemed bizarrely detached from the reality of his conduct. So he could not make good choices, and he could not sustain good relationships . .

Elliot had been a good role model, husband and father before his tumor.  After the tumor, he was

weirdly cool, detached, and ironic, indifferent even to intrusive discussion of personal matters- as if such remarks were not really about him. He had not previously been this way; he had been an affectionate husband and father. He retained lots of cognitive functions: he could perform calculations, had a fine memory for dates and names, and the ability to discuss abstract topics and world affairs.” After surgery, “he was even less able to care about things or to rank priorities. He could stick obsessively to a task and perform it well; but on a whim he might shift attention and do something completely different. Intelligence testing showed him to be a superior intellect.  His emotions were askew, though.  He could no longer set priorities or make decisions. He had no sense of the relative importance of any situation. 

Elliot could think but he couldn’t judge value.  “[T]the cold-bloodedness of Elliot’s reasoning prevented him from assigning different values to different options, and made his decision-making landscape hopelessly flat.”

Gage and Elliot each became like “Spock.” Many people would think of this as a potentially good thing, because they believe that emotions inevitably lead to “irrational” behavior.  The conventional wisdom is that people lacking emotions would be more clear-headed and therefore capable. What happened, though, is that both Gage and Elliot suffered severe impairments of judgment. Though they both appeared intelligent, they were completely incapable of making sensible personal and business decisions in the absence of emotions.

Damasio also studied other patients and found that people with flat affect were incapable of making decisions.   He found that pure rationality is helpless to make decisions.  Rational thought, devoid of emotion, paralyzes us.  He found that emotions are a necessary condition to allow rational decisions to be made, even purely “logical” decisions.  “Rationality” describes the way brain-damaged people make decisions.   Even “our most refined thoughts . . . use the body as a yardstick.”  He was convinced that the traditional views on the nature of rationality were therefore incorrect:

I had been advised early in life that sounds decisions came from a cool head … I had grown up accustomed to thinking that the mechanisms of reason existed in a separate province of the mind, where emotion should not be allowed to intrude, and when I thought of the brain behind that mind, I envisioned separate neural systems for reason and emotion … But now I had before my eyes the coolest, least emotional, intelligent human being one might imagine, and yet his practical reason was so impaired that it produced, in the wanderings of daily life, a succession of mistakes, a perpetual violation of what would be considered socially appropriate and personally advantageous.

Damasio was convinced that reason was “not be as pure as most of us think it is or wish it were, that emotion and feelings may not be intruders in the bastion of reason at all: they may be enmeshed in its networks, for worse and for better.”  He found that a reduction in emotion correlates with irrational behavior.  This “counterintuitive connection between absent emotion and warped behavior may tell us something about the biological machinery of reason.” The bottom line: pure reason is not sufficient for meaningful decision-making.

It is not only the separation between the mind and brain that is mythical: the separation between mind and body is probably just as fictional. The mind is embodied, in the full sense of the term, not just embrained.

The mind is actually about the body: the neural processes that are experienced as the mind concern the representation of the body in the brain.  Our minds critically depend on our human bodily existences.

“Somatic markers” comprise the emotional learning that we have acquired throughout our lives and that we then use for our daily decisions.  These markers record emotional reactions to situations.  Somatic markers work as emotionally-weighted indicators, steering us away from or toward choices, based on past experience.  It’s not that we can necessarily recall the specific past experiences that formed our system of markers, but we feel them and they allow us evaluate some options over others.  These emotion-laden markers help us to rank our options.

The brain does not merely record advance in the world but “also records how the body explores the world and reacts to it.”  Even though these neurological processes may occur in various portions of the brain, people experience and act on them in a unified coherent: the records that bind together all these fragmented activities . . . are embodied in ensembles of neurons.”  Damasio refers to these zones as “convergence zones,” where

The axons of feedforward projecting neurons from one part of the brain converge and join with reciprocally divergent feedback projections from other regions.  When a reactivation within the convergence zones stimulates the feedback projections, many anatomically separate and widely distributed neuron ensembles fire simultaneously and reconstruct previous patterns of mental activity. 

“Brain and Language,” Scientific American, 89-91 (September 1992).

Far from being a limitation or distraction, then, emotion is an integral part of cognition.  Emotion constructs and maintains the somatic markers that allow us to evaluate the desirability of our actions.

Spock would have struggled for hours to decide simple matters, such as what to eat.  That’s what pure rationality really gets you.

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