Brewer, the neuroscientist who studies meditation, has found that a felt
sense of expansion in consciousness correlates with a drop in activity in
one particular node of the default mode network—the posterior cingulate
cortex (PCC), which is associated with self-referential processing. One of
the most interesting things about a psychedelic experience is that it
sharpens one’s sensitivity to one’s own mental states, especially in the
days immediately following. The usual seamlessness of consciousness is
disturbed in such a way as to make any given state—mind wandering,
focused attention, rumination—both more salient and somewhat easier to
manipulate. In the wake of my psychedelic experiences (and, perhaps, in
the wake of interviewing Judson Brewer), I found that when I put my
mind to it, I could locate my own state of consciousness on a spectrum
ranging from contraction to expansion.
When, for example, I’m feeling especially generous or grateful, open to
feelings and people and nature, I register a sense of expansion. This
feeling is often accompanied by a diminution of ego, as well as a falloff in
the attention paid to past and future on which the ego feasts. (And
depends.) By the same token, there is a pronounced sense of contraction
when I’m obsessing about things or feeling fearful, defensive, rushed,
worried, and regretful. (These last two feelings don’t exist without time
travel.) At such times, I feel altogether more me, and not in a good way. If
the neuroscientists are right, what I’m observing in my mind has a
physical correlate in the brain: the default mode network is either online
or off; entropy is either high or low. What exactly to do with this
information I’m not yet sure.
• • •
BY NOW, it may be lost to memory, but all of us, even the psychedelically
naive, have had direct personal experience of an entropic brain and the
novel type of consciousness it sponsors—as a young child. Baby
consciousness is so different from adult consciousness as to constitute a
mental country of its own, one from which we are expelled sometime
early in adolescence. Is there a way back in? The closest we can come to
visiting that foreign land as adults may be during the psychedelic journey.
This at least is the startling hypothesis of Alison Gopnik, a developmental