title: Biphasic effects of propranolol on extinction of rewarded responding.
abstract: The effect of propranolol (5 mg/kg intraperitoneally) was investigated on the extinction of: (i) lever-pressing reinforced on a random interval (RI 64 s) schedule; and (ii) continuously reinforced running (1 min intertrial interval). Although there was evidence of an initial effect in each case to facilitate responding (increased rate of lever-pressing or speed of running), the opposite effect emerged as extinction continued; that is, propranolol promoted extinction. These results are inconsistent with the author's hypothesis, suggested by earlier studies, that acute administration of propranolol antagonizes the inhibitory effects of non- reward on behaviour.
authors.affiliation: Department of Psychology, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: P
authors.initials: P
authors.lastname: Salmon