REVERSAL LEARNING ENHANCED BY LYSERGIC ACID DIETHYLAMIDE (LSD): CONCOMITANT RISE IN BRAIN 5‐HYDROXYTRYPTAMINE LEVELS
British Journal of Pharmacology – November 01, 1974
Source: OpenAlex
Summary
Small doses of lysergic acid diethylamide (LSD) significantly enhanced learning in a brightness discrimination task, with participants showing improved performance at doses between 12.5–50 μg/kg. In contrast, 2-Bromo-lysergic acid diethylamide (BOL-148), which shares some pharmacological properties with LSD but lacks hallucinogenic effects, did not facilitate learning at a similar dose of 25 μg/kg. Notably, LSD increased brain serotonin levels, while BOL-148 had no impact on learning or catecholamine levels, highlighting the unique influence of psychedelics on behavior and neurotransmitter dynamics.
Abstract
Small doses of lysergic acid diethylamide (LSD) (12.5–50 μg/kg) consistently facilitated learning of a brightness discrimination reversal. 2‐Bromo‐lysergic acid diethylamide (BOL‐148), a structural analogue of LSD, with similar peripheral anti‐5‐hydroxytrypamine activity but no psychotomimetic properties, had no effect in this learning situation at a similar dose (25 μg/kg). LSD, but not BOL‐148, caused a small but significant increase in brain 5‐hydroxytryptamine levels, but had no effect on the levels of catecholamines in the brain at 25 μg/kg.