Low-dose lysergic acid diethylamide alters subjective visual perception but not visual contrast surround suppression

This randomised, double-blind, within-subjects crossover study (n=30) found that low-dose LSD (10 or 20 μg) changed participants’ subjective visual experiences, making vision seem blurrier, more saturated and more dynamic, but did not alter contrast surround suppression, a visual illusion linked to contextual processing.