caa a22 4500 469120673 CHVBK 20180323133138.0 cr unu---uuuuu 170328e19920601xx s 000 0 eng 10.1007/BF02245164 doi (NATIONALLICENCE)springer-10.1007/BF02245164 Impaired acquisition of temporal differentiation performance following lesions of the ascending 5-hydroxytryptaminergic pathways [Elektronische Daten] [Mary Wogar, C. Bradshaw, E. Szabadi] Nineteen rats received injections of 5,7-dihydroxytryptamine into the dorsal and median raphe nuclei; 16 rats received sham injections. The rats underwent 50 daily training sessions under an interresponse-time-greater-than-15-seconds (IRT >15 s) schedule of sucrose reinforcement. The lesioned group showed impaired acquisition of temporal differentiation, in that their response rates remained significantly higher and their obtained reinforcement frequencies significantly lower than those of the control (sham-lesioned) group. Comparison of the IRT frequency distributions obtained from the two groups during the last 5 days of training showed that the lesioned group produced a significantly higher proportion of very short IRTs (<3 s) than the control group; when these short IRTs were disregarded, the lesioned group displayed a significantly lower mean IRT and a significantly higher coefficient of variation than the control group. The levels of 5-hydroxytryptamine (5HT) and 5-hydroxyindoleacetic acid in the parietal cortex, hippocampus, amygdala, nucleus accumbens and hypothalamus were markedly reduced in the lesioned group, but the levels of noradrenaline and dopamine were not significantly affected by the lesion. The results suggest that destruction of the ascending 5HTergic pathways may reduce animals' capacity to inhibit positively reinforced operant behaviour, and may impair temporal discrimination. Springer-Verlag, 1992 5-Hydroxytrytamine nationallicence Lesion nationallicence Operant behaviour nationallicence Temporal differentiation nationallicence IRT>t schedule nationallicence Rat nationallicence Wogar Mary Department of Psychiatry, University of Manchester, Stopford Building, Oxford Road, M13 9PT, Manchester, UK aut Bradshaw C. Department of Psychiatry, University of Manchester, Stopford Building, Oxford Road, M13 9PT, Manchester, UK aut Szabadi E. Department of Psychiatry, University of Manchester, Stopford Building, Oxford Road, M13 9PT, Manchester, UK aut Psychopharmacology Springer-Verlag 107/2-3(1992-06-01), 373-378 0033-3158 107:2-3<373 1992 107 213 https://doi.org/10.1007/BF02245164 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02245164 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wogar Mary Department of Psychiatry, University of Manchester, Stopford Building, Oxford Road, M13 9PT, Manchester, UK aut NATIONALLICENCE 700 1- Bradshaw C. Department of Psychiatry, University of Manchester, Stopford Building, Oxford Road, M13 9PT, Manchester, UK aut NATIONALLICENCE 700 1- Szabadi E. Department of Psychiatry, University of Manchester, Stopford Building, Oxford Road, M13 9PT, Manchester, UK aut NATIONALLICENCE 773 0- Psychopharmacology Springer-Verlag 107/2-3(1992-06-01), 373-378 0033-3158 107:2-3<373 1992 107 213 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer