Blood Flow and Cerebral Laterality in the Mescaline Model of Psychosis
Leo Hermle, Euphrosyne Gouzoulis‐mayfrank, Matthew W. Spitzer
Pharmacopsychiatry July 1, 1998 DOI: 10.1055/s-2007-979352 via OpenAlex
Summary
AI-generated from the abstractIn 12 healthy men, mescaline triggered an acute psychotomimetic state resembling psychosis, measured by psychiatric scales, and specifically affected visual perception. Neuropsychological tests showed reduced right-hemisphere function, while brain imaging revealed increased frontal lobe activity, especially on the right side, which correlated with the psychotic-like symptoms. These results challenge the idea that reduced frontal lobe activity (hypofrontality) explains acute psychotic symptoms.
Study at a glance
| Characteristics | Experimental study Peer reviewed |
|---|---|
| Sample size | 12 |
| Population | Normal male volunteers |
| Intervention | Mescaline |
| Topics | Mescaline |
| Keywords | Psychotomimetic Neuropsychology Laterality Hallucinogen |
| Citations | 44 |
| Key finding | Mescaline induced a psychotomimetic state with decreased right hemisphere function on a neuropsychological task but increased right hemisphere activity on brain imaging, questioning hypofrontality as an explanation for acute psychosis. |
Abstract
The psychological, neuropsychological, and neurometabolic effects of the hallucinogenic agent mescaline were investigated in 12 normal male volunteers. Between 3 1/2 and 4 hours after drug intake, mescaline produced an acute psychotomimetic state, as measured by the BPRS and PDS-P. The APZ questionnaire revealed the specific effects of mescaline in the visual system. Neuropsychological effects were studied with a face/non-face decision task with known right hemisphere advantage, in which mescaline induced a decrease in functioning of the right hemisphere. In functional brain imaging using SPECT, mescaline produced a "hyperfrontal" pattern with an emphasis on the right hemisphere, which was correlated with mescaline-induced psychotomimetic psychopathology. Our findings question the validity of the concept of hypofrontality as an explanation for acute psychotic symptomatology.