Neuropsychological Assessment of Undergraduate Marihuana and LSD Users
Archives of General Psychiatry November 1, 1974 DOI: 10.1001/archpsyc.1974.01760170093015 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Population | College seniors |
| Duration | One-year replication |
| Topics | LSD Mescaline |
| Keywords | Neuropsychology Hallucinogen Neuropsychological test Clinical psychology Cognition |
| Citations | 53 |
| Key findings | LSD/mescaline users performed significantly worse on the Trail Making Test than marijuana/hashish users and controls, even after controlling for alcohol use. |
Abstract
An extended battery of neuropsychological tests was administered to three groups of college seniors (lysergic acid diethylamide [LSD]/mescaline users; marihuana/hashish users; and controls) who were matched on predrug usage intellectual and personality dimensions. The study was replicated one year later. In the combined-years' analyses, the three groups showed statistically significant differences only on the Trail Making Test: LSD/mescaline users performed within normal limits but significantly worse than either of the other two groups. Since the three groups also differed significantly in the extent of their alcohol usage, a covariance analysis was carried out that indicated that this variable did not account for the LSD/mescaline group's performance on the Trail Making Test. Inference about possible organic dysfunction cannot be drawn from these findings, but prospective neuropsychological testing might prove useful.