Effect of an acute d-amphetamine administration on context information memory in healthy volunteers: evidence from a source memory task.
BACKGROUND
Previous research demonstrated a positive effect of d-amphetamine on long-term verbal memory. An improvement in memory for contextual information is proposed as a possible mechanism underlying the d-amphetamine facilitation effect.


OBJECTIVE
A double blind, placebo controlled experiment was used to examine the processes involved in episodic memory affected by an acute administration of d-amphetamine. We investigated whether positive effects of d-amphetamine on item memory could be extended to context information by using a source memory paradigm.


METHODS
In a within-subjects design with two sessions, two study lists were presented in each session and participants were required to make an old/new recognition decision (item memory) and a list discrimination judgement (source memory) after delays of 1 h, 1 day and 1 week.


RESULTS
Enhancement of item memory after d-amphetamine intake was observed on delayed tests only, confirming that amphetamine does not affect short-term memory or memory acquisition, but rather a process operating after initial encoding. Importantly, we found an enhancement in remembering the source of recognized items after d-amphetamine administration.


CONCLUSIONS
The present study suggests that an acute administration of d-amphetamine helps to bind different features of an item in memory, in turn leading to an increased ability to recollect both the item and its context.
Zeeuws
Inge
I
Department of Experimental and Applied Psychology, Vrije Universiteit Brussel, Belgium.
Deroost
Natacha
N
Soetens
Eric
E
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000187:drug effects* / Q000502:physiology; D000697:Central Nervous System Stimulants / Q000008:administration & dosage* / Q000494:pharmacology; D018592:Cross-Over Studies; D003627:Data Interpretation, Statistical; D003913:Dextroamphetamine / Q000008:administration & dosage* / Q000494:pharmacology; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D011939:Mental Recall / Q000187:drug effects*; D012153:Retention, Psychology / Q000187:drug effects*; D055815:Young Adult
D000697:Central Nervous System Stimulants; D003913:Dextroamphetamine