How to Change Your Mind

Yet the fact that psychedelics have produced such a signal across a
range of indications can be interpreted in a more positive light. When a
single remedy is prescribed for a great many illnesses, to paraphrase
Chekhov, it could mean those illnesses are more alike than we’re
accustomed to think. If a therapy contains an implicit theory of the
disorder it purports to remedy, what might the fact that psychedelic
therapy seems to address so many indications have to tell us about what
those disorders might have in common? And about mental illness in
general?
I put this question to Tom Insel, the former head of the National
Institute of Mental Health. “It doesn’t surprise me at all” that the same
treatment should show promise for so many indications. He points out
that the DSM—the Diagnostic and Statistical Manual of Mental
Disorders, now in its fifth edition—draws somewhat arbitrary lines
between mental disorders, lines that shift with each new edition.
“The DSM categories we have don’t reflect reality,” Insel said; they
exist for the convenience of the insurance industry as much as anything
else. “There’s much more of a continuum between these disorders than
the DSM recognizes.” He points to the fact that SSRIs, when they work,
are useful for treating a range of conditions besides depression, including
anxiety and obsessive-compulsive disorder, suggesting the existence of
some common underlying mechanism.
Andrew Solomon, in his book The Noonday Demon: An Atlas of
Depression, traces the links between addiction and depression, which
frequently co-occur, as well as the intimate relationship between
depression and anxiety. He quotes an expert on anxiety who suggests we
should think of the two disorders as “fraternal twins”: “Depression is a
response to past loss, and anxiety is a response to future loss.” Both
reflect a mind mired in rumination, one dwelling on the past, the other
worrying about the future. What mainly distinguishes the two disorders is
their tense.
A handful of researchers in the mental health field seem to be groping
toward a grand unified theory of mental illness, though they would not be
so arrogant as to call it that. David Kessler, the physician and former
head of the FDA, recently published a book called Capture: Unraveling
the Mystery of Mental Suffering that makes the case for such an
approach. “Capture” is his term for the common mechanism underlying