title: Pharmacological studies of performance on the free-operant psychophysical procedure.
abstract: In the free-operant psychophysical procedure (FOPP), reinforcement is provided intermittently for responding on lever A in the first half and lever B in the second half of a trial. Temporal differentiation is measured from the psychometric function (percent responding on B, %B, versus time from trial onset, t), the index of timing being T50, the value of t at %B=50. T50 is reduced by acute treatment with 5-hydroxytryptamine (5-HT1A, 5-HT2A) and dopamine (D1-like, D2-like) receptor agonists. The effects of the agonists can be reversed by the respective antagonists of these receptors. Evidence is reviewed suggesting that the effect of endogenous 5-HT is mediated by 5-HT2A receptors and the effect of endogenous dopamine by D1-like receptors. Data are presented on the effects of lesions of the prefrontal cortex and corpus striatum on the sensitivity of performance on the FOPP to D1-like and D2-like receptor agonists. Lesions of the nucleus accumbens, but not the dorsal striatum or prefrontal cortex, attenuated the effects of a D1-like receptor agonist, 6-chloro-2,3,4,5-tetrahydro-1-phenyl-1H-3-benzazepine [SKF-81297], but not a D2-like receptor agonist, quinpirole, on T50. The results indicate that a population of D1-like receptors in the ventral striatum may contribute to the control of timing performance on the FOPP.
authors: Psychopharmacology Section, Division of Psychiatry, University of Nottingham, NG7 2UH, UK. steph_body@hotmail.co.uk
authors: S
authors: S
authors: Body
authors: T H C
authors: TH
authors: Cheung
authors: L
authors: L
authors: Valencia-Torres
authors: C M
authors: CM
authors: Olarte-Sánchez
authors: K C F
authors: KC
authors: Fone
authors: C M
authors: CM
authors: Bradshaw
authors: E
authors: E
authors: Szabadi
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003216:Conditioning, Operant / Q000187:drug effects*; D003342:Corpus Striatum / Q000187:drug effects*; D018491:Dopamine Agonists / Q000494:pharmacology*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D005260:Female; D017397:Prefrontal Cortex / Q000187:drug effects*; D017378:Quinolinic Acid / Q000633:toxicity; D051381:Rats; D017208:Rats, Wistar; D012702:Serotonin Antagonists / Q000494:pharmacology*
chemical_list: D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D012702:Serotonin Antagonists; D017378:Quinolinic Acid