Lasting changes in brain function occur quickly after a single LSD treatment, according to a recent study published in Neuropsychopharmacology. The research, led by Margaret Foley, aimed to investigate the acute and longer-term effects of LSD on motor learning and perceptual processing in healthy human subjects.
The study involved 45 participants between the ages of 21 and 55, who received one dose of 100µg LSD and one inactive placebo. The participants underwent a sequence typing task to assess motor learning, as well as auditory tetanization with electroencephalography and paired associative stimulation with transcranial magnetic stimulation to examine perceptual processing. Self-report measures, including questionnaires on perceived stress and cognitive flexibility, were also used to evaluate psychological functioning.
The results showed that LSD induced mostly positive acute and lasting subjective effects, as well as transient side effects. The participants who received LSD showed significant selective improvements in motor memory consolidation, particularly in speed, the day after dosing. There was no change in accuracy, suggesting that the effect on speed does not simply reflect a speed-accuracy trade-off.
The researchers speculated that these improvements may be due to enhanced neuroplasticity or possibly the post-drug exposure effects on motivation, attention, and/or arousal of the subjects. The findings are consistent with animal studies, which have shown that LSD can improve motor skills and performance across different learning paradigms, including classical and operant conditioning, fear extinction, and social reward learning.
The study’s findings suggest that a single treatment with LSD may broadly enhance synaptic plasticity in brain regions critical for learning and paying attention. However, the duration of these benefits remains to be determined.
Previous studies have investigated the effects of LSD on visuospatial learning and memory consolidation, but this study is the first to demonstrate improvements in motor learning after a psychedelic drug. The researchers suggest that LSD may open a critical learning period, characterized by increased aspects of neuroplasticity, in which learning is more efficient for at least a few days after dosing.
The study’s results have significant implications for the development of LSD as a potential treatment for psychiatric disorders, including major depressive disorder, anxiety disorders, and substance use disorders. Further research is needed to fully understand the effects of LSD on brain function and behavior.
