title: The effects of scopolamine on retrieval from semantic memory.
abstract: The effects of two doses of scopolamine (0.6 and 1.2 mg p.o.) on retrieval from semantic memory in normal young volunteers were examined using tests of verbal fluency and categorization latency. A visual contrast sensitivity test, which has previously shown a scopolamine-induced impairment at these doses (Broks et al., 1988), was also administered. In agreement with the work of Dunne (1990) and others, no evidence for a scopolamine deficit in semantic retrieval was found; in fact scopolamine improved letter fluency. However, scopolamine did produce the expected decrease in visual contrast sensitivity. The doses of scopolamine used here have also been shown to impair learning and attention (Broks et  al., 1988). It is possible that earlier studies which found a scopolamine deficit on semantic retrieval, did so because they used elderly subjects and/or large drug doses.
authors.affiliation: Department of Clinical Neuroscience, Merck Sharp & Dohme Research Laboratories, Neuroscience Research Centre, Terlings Park, Eastwick Road, Harlow, Essex CM20 2QR, UK.
authors.forename: C R
authors.initials: CR
authors.lastname: Lines
authors.forename: G C
authors.initials: GC
authors.lastname: Preston
authors.forename: P
authors.initials: P
authors.lastname: Broks
authors.forename: C E
authors.initials: CE
authors.lastname: Dawson