Effect of central 5-hydroxytryptamine depletion on performance in the ''time left'' procedure: further evidence for a role of the 5-hydroxytryptaminergic pathways in behavioural ''switching''

被引:17
作者
AlRuwaitea, ASA [1 ]
AlZahrani, SSA [1 ]
Ho, MY [1 ]
Bradshaw, CM [1 ]
Szabadi, E [1 ]
机构
[1] UNIV NOTTINGHAM,QUEENS MED CTR,DEPT PSYCHIAT,NOTTINGHAM NG7 2UH,ENGLAND
基金
英国医学研究理事会;
关键词
5-hydroxytryptamine; 5,7-dihydroxytryptamine; operant behaviour; timing; behavioural switching;
D O I
10.1007/s002130050440
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
This experiment examined the effect of destruction of the ascending 5-hydroxytryptaminergic (5HTergic) pathways on performance in a free-operant timing schedule: the ''time-left'' procedure. Rats received either injections of 5,7-dihydroxytryptamine into the dorsal and median raphe nuclei or sham lesions. They were trained in a discrete trials schedule in which reinforcers were provided for responding on either of two levers, A and B. At a random time point, t s after the start of each trial, a response on A resulted in the delivery of one food pellet after d(A) s, whereas a response on B resulted in the delivery of two pellets after 60-t s. The value of d(A) was varied between 1 and 8 s in different phases of the experiment. Both groups showed decreasing response rates on lever A and increasing response rates on lever B as a function of time within the trial. An index of timing (T-75: the time within the trial at which relative response rate on B attained a value of 75%) was systematically related to the value of d(A), but did not differ significantly between lesioned and control rats. However the lesioned group showed significantly higher rates of switching bi:tween response alternatives than the sham-lesioned group at all values of d(A). The levels of 5HT and 5-hydroxyindoleacetic acid were reduced in the brains of the lesioned rats, but the levels of noradrenaline and dopamine were not significantly altered. The results provide further evidence that the ascending 5HTergic pathways may contribute to the inhibitory regulation of switching between behavioural states.
引用
收藏
页码:179 / 186
页数:8
相关论文
共 32 条
[1]  
ALRUWAITEA ASA, 1997, TIME BEHAV PSYCHOL N
[2]   Effect of destruction of the 5-hydroxytryptaminergic pathways on behavioural timing and ''switching'' in a free operant psychophysical procedure [J].
AlZahrani, SSA ;
Ho, MY ;
Martinez, DNV ;
Cabrera, ML ;
Bradshaw, CM ;
Szabadi, E .
PSYCHOPHARMACOLOGY, 1996, 127 (04) :346-352
[3]   Effect of destruction of the 5-hydroxytryptaminergic pathways on the acquisition of temporal discrimination and memory for duration in a delayed conditional discrimination task [J].
AlZahrani, SSA ;
Ho, MY ;
Martinez, DNV ;
Cabrera, ML ;
Bradshaw, CM ;
Szabadi, E .
PSYCHOPHARMACOLOGY, 1996, 123 (01) :103-110
[4]  
[Anonymous], 1987, QUANTITATIVE ANAL BE
[5]  
AUTOR SM, 1960, THESIS HARVARD U
[6]  
BAUMGARTEN HG, 1982, BIOL SEROTONERGIC TR
[7]   PACEMAKER RATE IN THE BEHAVIORAL-THEORY OF TIMING [J].
BIZO, LA ;
WHITE, KG .
JOURNAL OF EXPERIMENTAL PSYCHOLOGY-ANIMAL BEHAVIOR PROCESSES, 1994, 20 (03) :308-321
[8]   CHOICE BETWEEN FIXED AND VARIABLE DELAYS WITH DIFFERENT REWARD AMOUNTS [J].
BRUNNER, D ;
GIBBON, J ;
FAIRHURST, S .
JOURNAL OF EXPERIMENTAL PSYCHOLOGY-ANIMAL BEHAVIORAL PROCESSES, 1994, 20 (04) :331-346
[9]  
DEAKIN JFW, 1983, THEORY PSYCHOPHAMACO, V2
[10]   EFFECTS OF COMBINED OR SEPARATE 5,7-DIHYDROXYTRYPTAMINE LESIONS OF THE DORSAL AND MEDIAN RAPHE NUCLEI ON RESPONDING MAINTAINED BY A DRL 20S SCHEDULE OF FOOD REINFORCEMENT [J].
FLETCHER, PJ .
BRAIN RESEARCH, 1995, 675 (1-2) :45-54