LSD, Time Perception, and Depression
For decades the effects of lysergic acid diethylamide (LSD) on the human brain have fascinated a wide range of “researchers” from actual scientists to movie stars like Cary Grant to the far-out hippies of the 60s.
And that fascination is not about to stop now.
A new brain scan study suggests that LSD causes decreased activity in the brain’s default mode network, which is active when people daydream or think about their past. As a result, study participants “tripping on acid” (as the vernacular goes) spent almost all of their altered state thinking about the present and future.
Each of 20 participants was given a dose of LSD in one session and a placebo dose in the other. Two hours after receiving their dose, researchers monitored participants’ brain activity using functional magnetic resonance imaging (fMRI). Afterwards, participants answered questions about what they had been thinking during the fMRI.
Participants thought dramatically less about the past when using LSD as compared to a placebo. At the same time, fMRI scans indicate significantly lower default mode network activity following LSD. Researchers believe these results support the view that at least some of the time perception effects are caused by the action of LSD on that particular brain network.
The hallucinogenic drug's positive time perception effects may someday prove useful to the development of therapies for people suffering from depression, one symptom of which is excessive preoccupation with the past.