Science
May 28, 1971
C H Hockman, R G Perrin, H Kalant
The administration of small doses of Delta(l)-tetrahydrocannabinol to cats with indwelling electrodes produced a disruption of both the electroencephalogram and behavior. Some of these alterations, including the appearance of a high-voltage slow wave electroencephalogram in the awake and moving animal, have been observed in cats that had been administered other drugs known to cause...
Canadian Psychiatric Association Journal
April 1, 1971
D. R. Campbell
Comparison was made among the electroencephalograms of eleven patients with psychotic reactions after the use of cannabis, twenty-nine patients admitted with a diagnosis of schizophrenia, ten for neurological consultations and eleven cannabis users with no apparent psychiatric implications. It was found that there was a greater increase in the EEG abnormalities of cannabis users than in the...
Clinical Pharmacology & Therapeutics
November 1, 1968
Leo E. Hollister, R. K. Richards, H. K. Gillespie
195 citations
A synthetic isomer of tetrahydrocannabinol (1‐Δ'‐3,4‐transtetrahydrocannabinol), believed to be identical to the most active naturally occurring THC, was compared with a semisynthetic THC‐like compound, synhexyl. Sixteen volunteer subiects received THC in doses ranging from 341 to 946 p.g per kilo gram (median 581). Thirteen subjects received synhexyl in doses ranging from 633 to 2,666 µg per...
Journal of Mental Science
October 1, 1958
Frances R. Ames
184 citations
This paper describes an inquiry into the effects of giving oral doses of the narcotic drug variously known as hashish, marihuana and, in South Africa, dagga. The drug is a preparation from the plant Cannabis sativa whose narcotic effect has been known for centuries. The writer's interest in it was inspired by the work in recent years on the mental disturbances produced by the active principles...
Clinical Neuropharmacology
Megan Jayne Ralston, Alim Osman
1 citation
This study reviews literature on the psychiatric effects of delta-8-THC, particularly psychosis and severe mental health outcomes, to highlight the need for further research and regulation. Marijuana, the most widely used illicit drug in the United States, sees increasing use due to legalization. Although moderate use is generally safe, adverse effects can occur, especially in those with...
Neuropsychopharmacology Reports
December 1, 2026
Yukina Kitano, Ryohei Takada, Minobu Ikehara et al.
ABSTRACT: Background: Cannabis use may cause psychotic symptoms, such as hallucinations and delusions, as well as persistent amotivation with reduced motivation, inactivity, and cognitive impairment. Although described as cannabis‐related amotivational syndrome, it is not recognized as an independent diagnostic entity and overlaps clinically with the negative symptoms of schizophrenia and mood...
Elizabeth J Davies, Natalie Ertl, Tom P. Freeman et al.
Adolescence is a critical period of brain development during which the endocannabinoid system continues to mature. These developmental changes may contribute to age-related differences in the association between cannabis use and large-scale functional network organisation, yet this association remains incompletely characterised. We hypothesised that regular cannabis use would be associated with...
Michael W. DeGregorio, Gregory T. Wurz
preprint
Abstract: Previous investigators have found no clear relationship between specific blood concentrations of D9-tetrahydrocannabinol (D9-THC) and impairment, and thus no scientific justification for use of legal “per se” D9-THC blood concentration limits. Analyzing blood from 30 subjects showed D9-THC concentrations that exceeded 5 ng/mL in 16 of the 30 subjects following a 12-hour period of...
Philippe Henry
preprint
Abstract: Cannabis can elicit various reactions in different consumers. In order to shed light on the mechanisms underlying the human-cannabis relationship, we begin to investigate the genetic basis of this differential response. The web-based platform OpenSNP was used to collect selfreported genetic and phenotypic data. Participants either reported a positively or negative affinity to...
Payal Jani, Nuri Song, Erin Artna et al.
BACKGROUND We have piloted a new online knowledge translation (KT) program created to educate youth about cannabis effects, which uniquely focuses on mental health risks for Black youth. Youth are generally unaware of the research linking underage usage and the risk of psychosis. Youth from some Black racialized communities in Ontario may be disproportionately affected and in need of this...