PLoS ONE
July 10, 2012
Janelle H. P. van Wel, Kim P. C. Kuypers, Eef L. Theunissen et al.
121 citations
MDMA increases both positive moods (vigor, arousal, friendliness, elation) and negative moods (anxiety, confusion) while also slowing reaction times on impulsivity tasks, indicating greater impulse control. Blocking 5-HT(2) receptors with ketanserin prevented the positive mood effects but not the negative mood or impulsivity changes. Blocking 5-HT(1) receptors with pindolol had no effect on any MDMA-related mood or impulse measures. Thus, 5-HT(2) receptors are specifically involved in MDMA's positive mood enhancement, while 5-HT(1) receptors do not appear to play a role in these effects.
Neuropsychopharmacology
May 11, 2011
Janelle H. P. van Wel, Kim P. C. Kuypers, Eef L. Theunissen et al.
52 citations
Blocking the 5-HT(2A) receptor with ketanserin prevented MDMA-induced impairment on a word-learning task, but not on spatial or prospective memory tasks. Blocking the 5-HT(1A) receptor with pindolol had no effect on any memory task. MDMA alone significantly impaired performance in all three memory tasks. The findings indicate that MDMA-induced verbal memory impairment is mediated by 5-HT(2A) receptor stimulation.
British Journal of Pharmacology
October 11, 2013
Janelle H. P. van Wel, Kim P. C. Kuypers, Eef L. Theunissen et al.
38 citations
Heavy cannabis users show broad impairments in neuropsychological function during THC intoxication, including reduced psychomotor performance and more errors on impulsivity tasks. These impairments appear less severe in psychomotor tasks than those previously seen in occasional users, suggesting some tolerance. Cocaine temporarily improves psychomotor function and speeds reaction times but increases errors, indicating a trade-off between stimulation and impulse control. The decline in impulse control may increase the risk of repeated drug use and addiction.
PLoS ONE
February 23, 2016
Kim P. C. Kuypers, Eef L. Theunissen, Janelle H. P. van Wel et al.
23 citations
Verbal memory performance in people who use Ecstasy (MDMA) does not differ from that of healthy non-users when they are not under the drug's influence, and there is substantial evidence supporting no long-term memory deficit. Clinically significant memory impairment—defined as performance more than 1.5 standard deviations below the average of healthy controls—was absent during abstinence. However, during acute MDMA intoxication, verbal memory was impaired. Pooled data from four experimental studies compared 65 Ecstasy users tested on placebo with 65 matched drug-naïve controls. History of use did not predict memory impairment. The findings suggest that Ecstasy/MDMA use does not cause clinically deficient long-term verbal memory.