Mescaline-induced psychopathological, neuropsychological, and neurometabolic effects in normal subjects: experimental psychosis as a tool for psychiatric research

Biol Psychiatry. 1992 Dec 1;32(11):976-91. doi: 10.1016/0006-3223(92)90059-9.


The psychological, neuropsychological, and neurometabolic effects of the hallucinogenic agent mescaline were investigated in 12 normal men who were volunteers. Mescaline produced an acute psychotic state 3 1/2-4 hr after drug intake, as measured by the Brief Psychiatric Rating Scale (BPRS) and Paranoid Depression Scale (PDS). The Assessment of Altered States of Consciousness (APZ) questionnaire revealed specific effects of mescaline in the visual system. Neuropsychological effects were studied with a face/nonface decision task with known right-hemisphere advantage, in which mescaline induced a decrease of functioning of the right hemisphere. In functional brain imaging using single photon emission computed tomography (SPECT), mescaline produced a "hyperfrontal" pattern with an emphasis on the right hemisphere, which was correlated with mescaline-induced psychotic psychopathology. Our findings question the validity of the concept of hypofrontality as an explanation for schizophrenic symptomatology. The study of psychoactive substances under controlled laboratory conditions has the methodological advantage of intraindividual control, and hence, minimal variability of data.

MeSH terms

  • Adult
  • Attention / drug effects
  • Attention / physiology
  • Brain Mapping / instrumentation
  • Cerebral Cortex / drug effects*
  • Cerebral Cortex / physiopathology
  • Discrimination Learning / drug effects
  • Discrimination Learning / physiology
  • Dominance, Cerebral / drug effects
  • Dominance, Cerebral / physiology
  • Energy Metabolism / drug effects*
  • Energy Metabolism / physiology
  • Frontal Lobe / blood supply
  • Humans
  • Image Processing, Computer-Assisted / instrumentation
  • Male
  • Mescaline / toxicity*
  • Middle Aged
  • Neurocognitive Disorders / physiopathology*
  • Neurocognitive Disorders / psychology
  • Neuropsychological Tests*
  • Pattern Recognition, Visual / drug effects
  • Pattern Recognition, Visual / physiology
  • Psychiatric Status Rating Scales*
  • Schizophrenia / chemically induced
  • Schizophrenia / physiopathology
  • Schizophrenic Psychology
  • Tomography, Emission-Computed, Single-Photon / instrumentation


  • Mescaline