LSD acutely impairs working memory, executive functions, and cognitive flexibility, but not risk-based decision-making
Psychological Medicine – September 10, 2019
Source: OpenAlex
Summary
LSD significantly impairs cognitive functions, particularly executive functions, cognitive flexibility, and working memory, as evidenced by a study involving 25 healthy participants. When compared to placebo, LSD (100 µg) led to notable deficits in tasks measuring these areas. However, pretreatment with the 5-HT 2A antagonist ketanserin (40 mg) effectively normalized these impairments. These findings underscore the potential of targeting the serotonin 5-HT 2A receptor to address cognitive dysfunctions associated with psychiatric and neurodegenerative conditions, offering insights into enhancing cognition through pharmacological interventions.
Abstract
Abstract Background Psychiatric and neurodegenerative illnesses are characterized by cognitive impairments, in particular deficits in working memory, decision-making, and executive functions including cognitive flexibility. However, the neuropharmacology of these cognitive functions is poorly understood. The serotonin (5-HT) 2A receptor might be a promising candidate for the modulation of cognitive processes. However, pharmacological studies investigating the role of this receptor system in humans are rare. Recent evidence demonstrates that the effects of Lysergic acid diethylamide (LSD) are mediated via agonistic action at the 5-HT 2A receptor. Yet, the effects of LSD on specific cognitive domains using standardized neuropsychological test have not been studied. Methods We examined the acute effects of LSD (100 µ g) alone and in combination with the 5-HT 2A antagonist ketanserin (40 mg) on cognition, employing a double-blind, randomized, placebo-controlled, within-subject design in 25 healthy participants. Executive functions, cognitive flexibility, spatial working memory, and risk-based decision-making were examined by the Intra/Extra-Dimensional shift task (IED), Spatial Working Memory task (SWM), and Cambridge Gambling Task (CGT) of the Cambridge Neuropsychological Test Automated Battery. Results Compared to placebo, LSD significantly impaired executive functions, cognitive flexibility, and working memory on the IED and SWM, but did not influence the quality of decision-making and risk taking on the CGT. Pretreatment with the 5-HT 2A antagonist ketanserin normalized all LSD-induced cognitive deficits. Conclusions The present findings highlight the role of the 5-HT 2A receptor system in executive functions and working memory and suggest that specific 5-HT 2A antagonists may be relevant for improving cognitive dysfunctions in psychiatric disorders.