How to Change Your Mind

brain but rather stem from an excess of order. When the grooves of self-
reflective thinking deepen and harden, the ego becomes overbearing. This
is perhaps most clearly evident in depression, when the ego turns on itself
and uncontrollable introspection gradually shades out reality. Carhart-
Harris cites research indicating that this debilitating state of mind
(sometimes called heavy self-consciousness or depressive realism) may
be the result of a hyperactive default mode network, which can trap us in
repetitive and destructive loops of rumination that eventually close us off
from the world outside. Huxley’s reducing valve contracts to zero.
Carhart-Harris believes that people suffering from a whole range of
disorders characterized by excessively rigid patterns of thought—
including addiction, obsessions, and eating disorders as well as
depression—stand to benefit from “the ability of psychedelics to disrupt
stereotyped patterns of thought and behavior by disintegrating the
patterns of [neural] activity upon which they rest.”
So it may be that some brains could stand to have a little more
entropy, not less. This is where psychedelics come in. By quieting the
default mode network, these compounds can loosen the ego’s grip on the
machinery of the mind, “lubricating” cognition where before it had been
rusted stuck. “Psychedelics alter consciousness by disorganizing brain
activity,” Carhart-Harris writes. They increase the amount of entropy in
the brain, with the result that the system reverts to a less constrained
mode of cognition.*
“It’s not just that one system drops away,” he says, “but that an older
system reemerges.” That older system is primary consciousness, a mode
of thinking in which the ego temporarily loses its dominion and the
unconscious, now unregulated, “is brought into an observable space.”
This, for Carhart-Harris, is the heuristic value of psychedelics to the study
of the mind, though he sees therapeutic value as well.
It’s worth noting that Carhart-Harris does not romanticize
psychedelics and has little patience for the sort of “magical thinking” and
“metaphysics” that they nourish in their acolytes—such as the idea that
consciousness is “transpersonal,” a property of the universe rather than
the human brain. In his view, the forms of consciousness that
psychedelics unleash are regressions to a “more primitive” mode of
cognition. With Freud, he believes that the loss of self, and the sense of
oneness, characteristic of the mystical experience—whether occasioned