Marijuana has been reported to alter the discrimination of time. The present study used a psychophysical approach to examine the effects of marijuana on temporal discrimination in humans. Research participants were required to push one of two buttons depending on the duration of a conditional stimulus (a blue square on a computer monitor). Correct choices ('C' button after a 2-s stimulus; 'A'...
Animal studies suggest that cannabinoid CB1 receptors play a role in regulating blood pressure (BP). In human studies, activation of CB1 receptors by cannabis or its active ingredient, Delta9-tetrahydrocannabinol (THC), has modest and inconsistent effects on BP. We evaluated this phenomenon in 63 male cannabis smokers (mean [SD] age 27.7 +/- 5.4 years, 70% African American, 10.3 +/- 5.9 years...
Many recreational ecstasy/MDMA users display neuropsychobiological de.cits, whereas others remain problem free. This review will investigate some of the drug and non-drug factors which in.uence the occurrence of these de.cits. Acute and chronic MDMA usage are both important. Intensive use within a session is often associated with more problems. In term of lifetime usage, novice users generally...
Repeated ecstasy (MDMA) use is reported to impair cognition and cause increased feelings of depression and anxiety. Yet, many relevant studies have failed to control for use of drugs other than MDMA, especially marijuana (THC). To address these confounding effects we compared behavioural performance of 11 MDMA/THC users, 15 THC users and 15 non-drug users matched for age and intellect. We...
The popular dance drug ecstasy (3,4-methylenedioxymethamphetamine -- MDMA) is neurotoxic upon central serotonergic neurons in laboratory animals and possibly also in humans. In recent years, several studies reported alterations of serotonergic transmission and neuropsychiatric abnormalities in ecstasy users which might be related to MDMA-induced neurotoxic brain damage. To date, the most...
Back to table of contents Previous article Next article Clinical & Research NewsFull AccessMarijuana-Induced Psychosis May Foretell Future EpisodesJoan Arehart-TreichelJoan Arehart-TreichelSearch for more papers by this authorPublished Online:3 Feb 2006https://doi.org/10.1176/pn.41.3.0023Reports from various researchers have suggested that marijuana-induced psychosis is generally short-lived...
Although little evidence supports cannabis-induced amotivational syndrome, sources continue to assert that the drug saps motivation 1, which may guide current prohibitions. Few studies report low motivation in chronic users; another reveals that they have higher subjective wellbeing. To assess differences in motivation and subjective wellbeing, we used a large sample (N = 487) and strict...
Immer mehr junge Menschen konsumieren Cannabis in manchmal hohen Dosierungen, wenn ihr Gehirn noch nicht voll entwickelt ist und besonders empfindlich auf äußere Einflüsse reagiert. Cannabis kann psychotische Zustände auslösen und verstärken, bereits an Schizophrenie Erkrankte exazerbieren bei Cannabiskonsum häufiger akut. Ersterkrankte Schizophrene mit vorherigem regelmäßigen Cannabiskonsum...
The genital-shrinking syndrome is a transient state of acute anxiety characterized by the triad of a deep-seated fear of penile shrinkage, its disappearance into the abdomen, and apprehension regarding inevitable impotence or even death. It is also known by the Malayo-Indonesian term 'koro'. In the West, koro syndrome has been reported only in relation with various somatic, psychiatric and...
Psychopathology2006E.J. Barkus, J. Stirling, R.S. Hopkins et al.
Objective: Recent studies have suggested that cannabis use is a risk factor for developing schizophrenia. We tested the hypothesis that cannabis use increases the likelihood of psychosis-like experiences in non-clinical participants who scored highly on a measure of schizotypy. Method: The psychological effects of cannabis were assessed in 137 healthy individuals (76% female, mean age 22 years)...
Cannabis use often induces subjective distortions of perception. However, little work has been done examining the electroencephalographic (EEG) correlates of early sensory processing in cannabis users. The present study therefore examined visual function in cannabis users as assessed via the steady state visual evoked potential. (SSVEP). SSVEPs were examined in current cannabis users (n = 17;...