Even if this premise were true — and many would consider it reductionist and simplistic — an undertaking as ambitious as unraveling the function of the brain would most likely take many years. Moreover, a complete understanding of neurobiology is unlikely to elucidate the complex interactions between genes and the environment that lie at the heart of many mental disorders. Anyone who thinks otherwise should remember the Decade of the Brain, which ended 15 years ago without yielding a significant clue about the underlying causes of psychiatric illnesses.

Sure, we now have astounding new techniques for studying the brain, like optogenetics, in which neurons can be controlled by light, allowing researchers to understand how neurons work alone and in networks. But no one thinks breakthrough biological treatments are just around the corner.

More fundamentally, the fact that all feelings, thoughts and behavior require brain activity to happen does not mean that the only or best way to change — or understand — them is with medicine. We know, for instance, that not all psychiatric disorders can be adequately treated with biological therapy. Personality disorders, like borderline and narcissistic personality disorders, which are common and can cause impairment and suffering comparable to that of severe depression, are generally poorly responsive to psychotropic drugs, but are very treatable with various types of psychotherapy.

There is often no substitute for the self-understanding that comes with therapy. Sure, as a psychiatrist, I can quell a patient’s anxiety, improve mood and clear psychosis with the right medication. But there is no pill — and probably never will be — for any number of painful and disruptive emotional problems we are heir to, like narcissistic rage and paralyzing ambivalence, to name just two.

Anyone who doubts the need for psychotherapy research should consider the case of post-traumatic stress disorder, for which the mainstay of treatment has been exposure therapy.

This requires patients to re-experience the circumstances of their traumatic event, which is meant to desensitize them and teach them that their belief that they are in danger is no longer true.

But we know that many patients with PTSD do not respond to exposure, and many of them find the process emotionally upsetting or intolerable.