Effects of guanfacine on three forms of distraction in the aging macaque.
alpha-2 adrenoceptor agonists, such as clonidine and guanfacine, enhance attention in aged animals. According to one theory, alpha-2 receptor agonists improve attention by decreasing distractibility to task-irrelevant stimuli. In two healthy aging bonnet macaques, we investigated the effects of low-(0.001 mg/kg) and high-dose (0.05 mg/kg) acute intramuscular guanfacine versus saline control on accuracy (number of trials correct) in three tasks requiring attention: delayed matching-to-sample, one-target visual tracking (test of focused attention) and two-target visual tracking (test of divided attention). Each task employed distracting stimuli in a different paradigmatic context. One monkey responded to guanfacine at both doses with significant rises in accuracy on all three tasks. The second monkey showed significant accuracy improvement for high-dose guanfacine only. No sedation was observed. These results suggest that guanfacine improves attention and reduces distractibility in multiple task contexts in healthy aging primates.
O'Neill
J
J
VA Sepulveda Medical Center, North Hills, CA 91343, USA. joneill@itsa.ucsf.edu
Fitten
L J
LJ
Siembieda
D W
DW
Ortiz
F
F
Halgren
E
E
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000375:Aging / Q000523:psychology*; D000818:Animals; D001288:Attention / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D016316:Guanfacine / Q000494:pharmacology*; D008255:Macaca radiata
D000316:Adrenergic alpha-Agonists; D016316:Guanfacine