Dopamine agonists disrupt visual latent inhibition in normal males using a within-subject paradigm.
Latent inhibition (LI) is the delayed learning of an association when the conditioned stimulus has previously been experienced out of the context of that association. LI can be measured across species and has been used to understand the neurobiology of schizophrenia, since some reports suggest that schizophrenia patients exhibit LI deficits. One challenge of LI studies in humans has resulted from the fact that LI paradigms have almost uniformly involved between-subject comparisons. We now report a new within-subject paradigm that detected LI in normal adult male subjects after ingestion of a placebo. After amphetamine (20 mg p.o.) or bromocriptine (1.25 mg p.o.), LI was not evident, suggesting that the LI detected by this paradigm is sensitive to disruption by dopamine agonists. The apparent advantages and limitations of this paradigm are discussed with regard to its future use in understanding the neural basis of reported LI deficits in schizophrenia.
Swerdlow
Neal R
NR
Department of Psychiatry, UCSD School of Medicine, 9500 Gilman Dr., La Jolla, CA 92093-0804, USA. nswerdlow@ucsd.edu
Stephany
Nora
N
Wasserman
Lindsay C
LC
Talledo
Jo
J
Sharp
Richard
R
Auerbach
Pamela P
PP
D000328:Adult; D000661:Amphetamine / Q000494:pharmacology; D000704:Analysis of Variance; D001245:Association Learning / Q000187:drug effects; D001971:Bromocriptine / Q000494:pharmacology*; D016022:Case-Control Studies; D003214:Conditioning, Classical / Q000187:drug effects*; D018491:Dopamine Agonists / Q000494:pharmacology*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D010775:Photic Stimulation; D011930:Reaction Time / Q000187:drug effects
D018491:Dopamine Agonists; D018765:Dopamine Uptake Inhibitors; D001971:Bromocriptine; D000661:Amphetamine