Desamino-D-arg8-vasopressin (DDAVP), unlike ethanol, has no effect on a boring visual vigilance task in humans

It has been suggested that vasopressin (VP) and its analogues such as desamino-D-arg8-vasopressin (DDAVP) affect cognitive (including mnemonic) and attentional processes in man. We describe the effects of DDAVP and ethanol (EtOH) on young, healthy human volunteers, using a recently developed visual search task which assesses attention and vigilance. Over a 1-h session, the subject has to detect the occurrence of certain digits in a long list of random characters. A low dose of EtOH (0.33 ml/kg) tended to improve, and a higher dose (1.0 ml/kg) disrupted performance. DDAVP (20 or 60 micrograms/subject) had no effect whatsoever. It is concluded that intranasal administration of the peptide analogue does not markedly affect attention performance in human subjects.