British Journal of Pharmacology
October 11, 2013
Janelle H. P. van Wel, Kim P. C. Kuypers, Eef L. Theunissen et al.
38 citations
BACKGROUND AND PURPOSE: Cannabis is the most popular drug used in the European Union, closely followed by cocaine. Whereas cannabis impairs neurocognitive function in occasional cannabis users, such impairments appear less prominent in heavy users, possibly as a result of tolerance. The present study was designed to assess whether the impairing effects of Δ(9) -tetrahydrocannabinol (THC) in...
British Journal of Pharmacology
September 4, 2012
Kim P. C. Kuypers, Rafael de la Torre, Magı́ Farré et al.
23 citations
BACKGROUND: Ecstasy use is commonly linked with memory deficits in abstinent ecstasy users. Similar impairments are being found during ecstasy intoxication after single doses of ± 3,4 metylenedioxymethamphetamine (MDMA). The concordance of memory impairments during intoxication and abstinence suggests a similar neuropharmacological mechanism underlying acute and chronic memory impairments. The...
PLoS One
July 10, 2012
Janelle H. P. van Wel, Kim P. C. Kuypers, Eef L. Theunissen et al.
121 citations
UNLABELLED: MDMA induces positive mood and increases impulse control during intoxication, but only a few studies on the neuropharmacological mechanisms underlying these processes have been conducted. It was hypothesized that pretreatment with 5-HT(1) and 5-HT(2) receptor blockers would prevent MDMA effects on mood and impulsivity. Subjects (N = 17) participated in a double-blind, placebo...
Psychopharmacology
September 27, 2011
Wendy M. Bosker, Kim P. C. Kuypers, Silke Conen et al.
32 citations
RATIONALE: Experimental research has shown that 3,4-methylenedioxymethamphetamine (MDMA) can improve some psychomotor driving skills when administered during the day. In real life, however, MDMA is taken during the night, and driving may likely occur early in the morning after a night of "raving" and sleep loss. OBJECTIVES: The present study assessed the effects of MDMA on road-tracking and...
Journal of Psychopharmacology
May 26, 2011
Kim P. C. Kuypers, Marleen Wingen, Armin Heinecke et al.
19 citations
The aim of the present study was to identify the neural substrate underlying memory impairment due to a single dose of MDMA (3,4-methylenedioxymethamphetamine) by means of pharmaco-MRI. Based on previous behavioral results it was hypothesized that this deficit could be attributed to a specific influence of MDMA on encoding. Fourteen Ecstasy users participated in this double-blind,...
Neuropsychopharmacology
May 11, 2011
Janelle H. P. van Wel, Kim P. C. Kuypers, Eef L. Theunissen et al.
52 citations
3,4-Methylenedioxymethamphetamine (MDMA) or 'ecstasy' has been associated with memory deficits during abstinence and intoxication. The human neuropharmacology of MDMA-induced memory impairment is unknown. This study investigated the role of 5-HT(2A) and 5-HT(1A) receptors in MDMA-induced memory impairment. Ketanserin is a 5-HT(2A) receptor blocker and pindolol a 5-HT(1A) receptor blocker. It...
Psychopharmacology
January 18, 2010
Wendy M. Bosker, Kim P. C. Kuypers, Silke Conen et al.
45 citations
INTRODUCTION: 3,4-methylenedioxymethamphetamine (MDMA) is known to improve psychomotor function and mood when measured during daytime. However, MDMA users tend to take this drug at dance parties while staying awake for prolonged periods of time. SUBJECTS AND METHODS: This study was designed to assess dose-related residual effects of MDMA on psychomotor function and mood after a night without...
2007
Kim P. C. Kuypers
2 citations
In addition to the positive effects, ecstasy use is also accompanied by short-term side effects occurring early, with respect to administration, and later on.Early short time side effects i.e. fatigue, lack of energy and difficulty concentrating, arise approximately 24 hours after MDMA ingestion.Late short-term side effects occur up to 7 days post-drug and are more or less comparable to early...
Journal of Psychopharmacology
November 1, 2005
Kim P. C. Kuypers, Jan Ramaekers
88 citations
A range of studies has indicated that users of 3.4-Methylene-dioxymethamphetamine (MDMA, 'Ecstasy') display cognitive deficits, particularly memory impairment, as compared to non-drug using controls. Yet it is difficult to determine whether these deficits are caused by MDMA or some other confounding factor, such as polydrug use. The present study was designed to establish the direct relation...