Moderate psychosocial stress appears not to impair recall of words learned 4 weeks prior to stress exposure.
Recent studies in humans have reported that recall of previously learned material is especially sensitive to the disruptive effects of pharmacologically induced cortisol elevations. Whether similar effects occur after exposure to psychosocial stress remains to be shown. Moreover it is unknown whether stress before or after the initial learning interacts with the later effects of repeated stress on delayed recall (e.g. state-dependent learning). Forty subjects participated in the present experiment. They learned a word list either one hour before or 10 min after exposure to a psychosocial laboratory stressor. Delayed recall was tested 4 weeks later, again either before or after stress. Salivary cortisol levels increased significantly in response to both stress exposures. Stress had no effects on the initial learning and also did not impair delayed recall. Moreover there was no evidence for state-dependent learning. The current data seem to be in conflict with previous studies demonstrating that delayed recall is especially sensitive to elevated cortisol levels. Several reasons for these discrepancies are discussed. Among them is the small sample size, the moderate cortisol increase in response to the second stress exposure but also the long recall delay, which might lead to memory traces less susceptible to stress.
Wolf
Oliver T
OT
Institute of Experimental Psychology II, University of Duesseldorf, Duesseldorf, Germany. oliver.wolf@uni-duesseldorf.de
Schommer
Nicole C
NC
Hellhammer
Dirk H
DH
Reischies
Friedel M
FM
Kirschbaum
Clemens
C
D000328:Adult; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis; D007858:Learning; D008297:Male; D008568:Memory / Q000502:physiology*; D012463:Saliva / Q000737:chemistry; D013315:Stress, Psychological / Q000523:psychology*; D013997:Time Factors
D006854:Hydrocortisone