Information processing speed in ecstasy (MDMA) users.
Previous research draws parallels between ecstasy-related and age-related deficits in cognitive functioning. Age-related impairments in working memory have been attributed to a slow down in information processing speed. The present study compared 29 current ecstasy users, 10 previous users and 46 non-users on two tests measuring information processing speed and a computation span task measuring working memory. Results showed that ecstasy users performed worse than non-ecstasy users in the letter comparison task although the overall difference was not significant (p=0.089). Results from the pattern recognition task showed that current ecstasy users produced significantly more errors than the other two groups (p<0.01). When results were combined for both the letter and pattern tasks, once again current ecstasy users produced significantly more errors than non-ecstasy users (p<0.01). Working memory deficits obtained were statistically significant with both ecstasy using groups performing significantly worse than non-users on the computation span measure (p<0.01). Moreover, ANCOVA with measures of processing speed as covariates failed to eliminate the group difference in computation span (p<0.01). Therefore, it is likely the mechanism responsible for impairments in the computation span measure is not the same as that in elderly adults where processing speed generally removes most of the age-related variance. Also of relevance is the fact that the ecstasy users reported here had used a range of other drugs making it difficult to unambiguously attribute the results obtained to ecstasy use.
Wareing
Michelle
M
The Centre for Public Health, Liverpool John Moores University, Liverpool, UK. M.Wareing@ljmu.ac.uk
Fisk
John E
JE
Montgomery
Catharine
C
Murphy
Philip N
PN
Chandler
Martin D
MD
D000328:Adult; D000661:Amphetamine / Q000008:administration & dosage; D002188:Cannabis / Q000737:chemistry; D003042:Cocaine / Q000008:administration & dosage; D000431:Ethanol / Q000008:administration & dosage; D006801:Humans; D008568:Memory / Q000187:drug effects; D008606:Mental Processes / Q000187:drug effects; D015999:Multivariate Analysis; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000008:administration & dosage*; D010364:Pattern Recognition, Visual / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects; D015203:Reproducibility of Results; D012646:Self Administration; D019966:Substance-Related Disorders / Q000503:physiopathology* / Q000523:psychology; D011795:Surveys and Questionnaires; D013997:Time Factors
D000431:Ethanol; D000661:Amphetamine; D003042:Cocaine; D018817:N-Methyl-3,4-methylenedioxyamphetamine