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Jg Ramaekers

4 papers in the library · 100 citations · publishing 2008-2016

Papers

Memory and mood during the night and in the morning after repeated evening doses of MDMA

Journal of Psychopharmacology February 28, 2008 KPC Kuypers, M. Wingen, Jg Ramaekers 28 citations

Memory performance worsens progressively overnight due to sleep loss, and taking MDMA (ecstasy) in the evening adds to that impairment. In a double-blind, placebo-controlled crossover study with 14 healthy adults, MDMA (75 mg and 50 mg split over the evening) caused additional deficits in verbal and spatial memory beyond those from sleep deprivation alone. During the night, MDMA improved response speed and increased feelings of vigor, friendliness, elation, anxiety, confusion, arousal, and positive mood, but these effects returned to placebo-like levels by morning. Evening MDMA selectively impairs memory, and this harm is separate from and adds to the memory impairment caused by sleep deprivation.

Neurocognitive performance following acute mephedrone administration, with and without alcohol

Journal of Psychopharmacology August 25, 2016 EB de Sousa Fernandes Perna, Esther Papaseit, Clara Pérez‐mañá et al. 26 citations

Mephedrone, a recreational drug similar to MDMA, impairs short-term spatial memory one hour after intake but improves critical tracking performance four hours later. When combined with alcohol, mephedrone reduces reaction time compared to alcohol alone, but does not counteract alcohol's impairing effects on divided attention or spatial memory. Alcohol alone impairs both short- and long-term spatial memory and divided attention. The findings suggest mephedrone enhances psychomotor performance while harming memory, and its stimulatory effects are insufficient to offset alcohol-induced deficits on most cognitive tasks.

Psychedelic symptoms of cannabis and cocaine use as a function of trait impulsivity

Journal of Psychopharmacology January 8, 2015 JHP van Wel, DB Spronk, Kim P. C. Kuypers et al. 23 citations

Regular drug users with normal or high trait impulsivity levels showed largely similar subjective responses to cocaine, cannabis, and placebo. Cannabis increased dissociation, psychedelic symptoms, fatigue, confusion, depression, and anxiety while decreasing arousal, positive mood, vigor, friendliness, and elation. Cocaine increased dissociation, psychedelic symptoms, vigor, friendliness, elation, positive mood, anxiety, and arousal while decreasing fatigue. Only a few subjective measures differed by impulsivity level; psychedelic symptoms were most intense in high-impulsivity subjects. Trait impulsivity correlated negatively with vigor (r = -.197) and positively with loss of thought control (r = .237) during cannabis intoxication, but a broad association between trait impulsivity and psychedelic drug experience was absent.

Inhibition ofMDMA‐induced increase in cortisol does not prevent acute impairment of verbal memory

British Journal of Pharmacology September 4, 2012 Kim P. C. Kuypers, Rafael de la Torre, Magı́ Farré et al. 23 citations

MDMA acutely impairs memory, but this effect is not caused by the rise in cortisol that MDMA also triggers. In a placebo-controlled, within-subject experiment with 17 polydrug MDMA users, blocking the cortisol increase with metyrapone (a cortisol synthesis inhibitor) did not prevent the memory deficit produced by a 75 mg dose of MDMA. Memory was tested at peak drug concentrations. The finding suggests that the neuropharmacological mechanism behind MDMA-induced memory impairment is independent of cortisol.