Increased Activation of Indirect Semantic Associations under Psilocybin
Gouzoulis-Mayfrank, E., Heimann, H., Hermle, L., Holzmann, P., Kischka, U., Kovar, K., Schneider, F., Spitzer, M., Thimm, M.
This early double-blind, placebo-controlled study (1995, n=8) suggests that psilocybin increased indirect semantic priming. The authors add, however, that the setting alone led to a similar effect.
Abstract
Hypothesized that psilocybin might exert a defocusing effect on semantic networks (i.e., decrease the signal-to-noise ratio), which should lead to an increased indirect semantic priming effect. A double-blind, placebo-controlled study was conducted on the effects of psilocybin on semantic and indirect semantic priming with 8 normal males (mean age 39.4 yrs). The finding that psilocybin increases indirect semantic priming in normal Ss adds to the general understanding of the effects of hallucinogenic agents on cognitive functions. Data indicate that indirect semantic priming is a highly sensitive measure that appears to respond not only to pharmacologic intervention, but also to the psychological effects of the setting.