Electrophysiological indices of altered working memory processes in long-term ecstasy users

✍ Scribed by Claire Nulsen; Allison Fox; Geoff Hammond

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 171 KB
• Volume: 26
• Category: Article
• ISSN: 0885-6222
• DOI: 10.1002/hup.1231

✦ Synopsis

Objective

The aim of this study was to determine the effect of light long‐term ecstasy consumption on verbal short‐term and working memory and to identify the cognitive processes contributing to task performance.

Method

Electroencephalogram was recorded while ecstasy users (N = 11), polydrug users (N = 13), and non‐users (N = 13) completed forward and backward serial recognition tasks designed to engage verbal short‐term memory and verbal working memory, respectively.

Results

All three groups displayed significantly lower digit‐backward span than digit‐forward span with ecstasy users displaying the greatest difference. The parietally distributed P3b was significantly smaller in the digits backward task than in the digits forward task in non‐ecstasy‐using controls. Ecstasy users did not show the reduced P3b component in the backward task that was seen in both non‐ecstasy‐using control groups.

Conclusions

Ecstasy users' performance was suppressed more by the concurrent processing demands of the working memory task than that of the non‐ecstasy‐using controls. Non‐ecstasy‐using controls showed differential event‐related potential wave forms in the short‐term and working memory tasks, and this pattern was not seen in the ecstasy users. This is consistent with a reduction in the cognitive resources allocated to processing in working memory in ecstasy users. Copyright © 2011 John Wiley & Sons, Ltd.