Psilocybin slows binocular rivalry switching through serotonin modulation
Journal of Vision – March 19, 2010
Source: OpenAlex
Summary
The powerful hallucinogen psilocybin significantly slows binocular rivalry, the visual competition between eyes. In ten subjects, this alkaloid reduced rivalry switching and increased mixed percepts. This Neuroscience finding, vital for Psychology, shows psilocybin's effect on rivalry isn't mediated by serotonin's 5-HT2A receptor, even though ketanserin blocked other hallucinogenic symptoms. Such Psychedelics and Drug Studies reveal neurotransmitter receptor influence on behavior. Unlike Lysergic acid diethylamide, psilocybin's rivalry effect points to 5-HT1A, offering insights into chemical synthesis and brain function.
Abstract
Binocular rivalry refers to the fluctuations in visual awareness/suppression that occur when different images are simultaneously presented to each eye. To explore the role of serotonin (5-HT) in binocular rivalry, this study investigated the affects of the hallucinogenic 5-HT1A&2A receptor agonist psilocybin (the active compound in “magic mushrooms”), alone and after pretreatment with the selective 5-HT2A antagonist ketanserin in ten healthy human subjects. Psilocybin significantly reduced the rate of binocular rivalry switching and increased the proportion of transitional/mixed percept experience. Ketanserin pretreatment blocked the majority of psilocybin's “positive” psychosis-like hallucinogenic symptoms, but had no influence on the psilocybin induced slowing of binocular rivalry switching or the “negative” symptoms associated with reduced arousal and vigilance. This finding directly links binocular rivalry switching rate to arousal and attention and suggests that psilocybin induced slowing of binocular rivalry is not 5-HT2A mediated, but instead may reflect a 5-HT1A mediated reduction of serotonin release from the brainstem raphe nuclei.