Altered State of Consciousness and Mental Imagery as a Function of N, N-dimethyltryptamine Concentration in Ritualistic Ayahuasca Users.

Consumption of the psychedelic brew ayahuasca is a central ritualistic aspect of the Santo Daime religion. The current observational, baseline controlled study was designed to assess whether members (n = 24) of the Santo Daime church would show enhanced capacity for mental imagery during an ayahuasca experience. In addition, this study assessed whether the effects of ayahuasca on consciousness and mental imagery were related to peak serum concentration of N, N-dimethyltryptamine (DMT), the main psychoactive component. Measures of altered states of consciousness (5-Dimensional Altered States of Consciousness Questionnaire) and ego dissolution (Ego Dissolution Inventory [EDI]) as well as measures of mental imagery (visual perspective shifting, vividness of visual imagery, cognitive flexibility, associative thinking) were taken on two subsequent days on which members of Santo Daime were sober or drank a self-selected volume of ayahuasca. Measures of altered states of consciousness revealed that feelings of oceanic boundlessness, visual restructuralization, and EDI increased most prominently after drinking and shared a positive correlation with peak DMT concentration. Measures of mental imagery did not noticeably differ between the baseline and ayahuasca condition, although subjective ratings of cognitive flexibility were lower under ayahuasca. Two measures related to mental imagery, that is, perspective shifts and cognitive flexibility, were significantly correlated to peak DMT concentrations. Peak concentrations of DMT and other alkaloids did not correlate with ayahuasca dose. These findings confirm previous notions that the primary phenomenological characteristics of ayahuasca are driven by DMT. Compensatory or neuroadaptive effects associated with long-term ayahuasca intake may have mitigated the acute impact of ayahuasca in Santo Daime members on mental imagery.

Intoxication by a synthetic cannabinoid (JWH-018) causes cognitive and psychomotor impairment in recreational cannabis users.

BACKGROUND: Smoking mixtures containing synthetic cannabinoids (SCs) have become very popular over the last years but pose a serious risk for public health. Limited knowledge is, however, available regarding the acute effects of SCs on cognition and psychomotor performance. Earlier we demonstrated signs of impairment in healthy volunteers after administering one of the first SCs, JWH-018, even though subjective intoxication was low. In the current study, we aimed to investigate the acute effects of JWH-018 on several cognitive and psychomotor tasks in participants who are demonstrating representative levels of acute intoxication. METHODS: 24 healthy cannabis-experienced participants took part in this placebo-controlled, cross-over study. Participants inhaled the vapor of 75 µg JWH-018/kg body weight and were given a booster dose if needed to induce a minimum level of subjective high. They were subsequently monitored for 4 h, during which psychomotor and cognitive performance, vital signs, and subjective experience were measured, and serum concentrations were determined. RESULTS: Maximum subjective high (average 64%) was reached 30 min after administration of JWH-018, while the maximum blood concentration was shown after 5 min (8 ng/mL). JWH-018 impaired motor coordination (CTT), attention (DAT and SST), memory (SMT), it lowered speed-accuracy efficiency (MFFT) and slowed down response speed (DAT). CONCLUSION: In accordance with our previous studies, we demonstrated acute psychomotor and cognitive effects of a relatively low dose of JWH-018.