Undue modesty

We must not overhype brain science. But the real risk is that we underestimate it
February 24, 2010
Matter into Imagination 3 by Susan Aldworth, perspex plate on collagraph plate

Two basic dangers face the non-specialist when applying the insights of neuroscience. The first is to imagine that an empirical scientific practice, concerned with neurotransmitters and brain anatomy, will one day provide an explanation for most human experiences. It’s not just excitable dilettantes in the humanities and media who succumb to this fallacy, but also some excitable neuroscientists—who glimpse wider cultural and social potential in their work.

Perhaps the most famous example of this occurred when behavioural neurologist VS Ramachandran described “mirror” neurons—which fire up in monkeys both when they perform an action or observe it being performed—as “empathy” neurons. This was a category error, but was a literary slip rather than a scientific error. Both terms are metaphors, but while the simple metaphor of mirroring may usefully describe a chemical mechanism, “empathy” requires social context, narrative and psychological meaning. Ascribing complex human feeling to simple objects is what literary criticism calls the “pathetic fallacy.” The term is not one of abuse: the effects can be lovely. But in literature one wouldn’t confuse the “secrets of the human heart” with blood cells pumping through an aorta.

If neuroscience can’t explain an emotional phenomenon such as empathy, it certainly won’t be of help in forming social policy. This is why professional sceptics like Steven Rose insist on rigorous adherence to the limits of empirical discourse, and Raymond Tallis, both a medical scientist and a philosopher, delightfully scolds the purveyors of “neurotrash.”

But such scepticism also risks leading the rest of us into a second danger: the conclusion that studying the brain can tell us almost nothing important about human nature; that we could just as well stick to old Freudian models of the unconscious or sociological explanations of behaviour.

Neuroscience has helped identify and refine understanding of brain diseases, such as Parkinson’s or Alzheimer’s. The question is to what extent it has also helped identify conditions of the mind. In contrast to neurological conditions, psychiatric diagnoses such as bipolar disorder and schizophrenia are not strict physiological descriptions, reducible to brain circuitry. They are phenomenological concepts—descriptions of experience—searching for physiological origins. A doctor will talk to a patient about personal history when trying to identify the contributory psychological factors of a condition, and about an underlying neurochemical disorder when prescribing medication. Psychiatry is both doomed and privileged to operate in the middle of the mind-brain problem—it is influenced, but not determined, by what happens in our brains.

Neuroscience does not resolve the dualism inherent to the terms we use to describe mental states. But that does not mean it has nothing to say. Instead, it is providing us with new tools with which to rethink such problems. In 1973, for example, there were only 485 cases of Tourette syndrome diagnosed in the world. Many undiagnosed sufferers were subject to arbitrary psychoanalytic interpretations. In 1985, however, Oliver Sacks published his book The Man Who Mistook His Wife for a Hat, giving currency to the original, neurological interpretation of Tourette’s. Now we know that the basal ganglia, involved with motor control and learning, are implicated in not only this condition, but also perhaps in stammering, which was traditionally reduced to theories of childhood trauma. The neuroscientific tools cannot explain the psychological or social aspects of such conditions, but they certainly do help correct previous fallacies.

It’s hard to believe that Freud, who started life as a neurologist, would have ignored contemporary neuroscience. Instead, he would have investigated what could be learned from it. Neuro-anatomical maps—those which ascribe functions to discrete parts of the brain, viewed as coloured blobs on an MRI scan—are still only maps, riddled with conceptual pitfalls. They can never explain consciousness, if only because the language we use to describe consciousness cannot be cleansed of its often contradictory mind-terms and brain-terms. But even elementary maps serve as guides—and our brain terms are improving. We must not be so modest that we miss the real promise of neuroscience: as a tool to help us change the way we imagine ourselves.