title: Isolation-stress-induced facilitation of passive avoidance memory in the day-old chick.
abstract: This study showed that facilitation of recall of a weak version of the 1-trial passive avoidance learning task could be achieved by behavioral "stressing" of day-old chicks after training. Recall, usually retained for less than 9 hr, was extended by socially isolating the chicks for 1 hr immediately after training. There was a brief 3-fold increase in plasma corticosterone levels 10 min after isolation. Facilitated recall was not evident when chicks were isolated 2 hr after training, and it was blocked by intracerebral administration of 2-ng RU 38486, a specific glucocorticoid receptor antagonist, per chick. Male chicks responded more to isolation than did female chicks, presumably a consequence of the additional stress of the injection procedure.
authors.affiliation: Department of Biology, Open University, Milton Keynes, United Kingdom. a.b.johnston@open.ac.uk
authors.forename: A N
authors.initials: AN
authors.lastname: Johnston
authors.forename: S P
authors.initials: SP
authors.lastname: Rose
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn / Q000523:psychology*; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology*; D016009:Chi-Square Distribution; D002645:Chickens; D003345:Corticosterone / Q000097:blood*; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology; D005260:Female; D006727:Hormone Antagonists / Q000494:pharmacology; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D015735:Mifepristone / Q000494:pharmacology; D011965:Receptors, Glucocorticoid / Q000037:antagonists & inhibitors; D012054:Reinforcement, Psychology; D012153:Retention, Psychology / Q000187:drug effects / Q000502:physiology; D012737:Sex Factors; D012934:Social Isolation / Q000523:psychology; D013315:Stress, Psychological / Q000503:physiopathology*; D013649:Taste / Q000502:physiology; D013997:Time Factors
chemical_list: D006727:Hormone Antagonists; D011965:Receptors, Glucocorticoid; D015735:Mifepristone; D003345:Corticosterone