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851.
Alternation behavior, spatial discrimination, and reversal disturbances following 6-hydroxydopamine lesions in the nucleus accumbens of the rat 总被引:3,自引:0,他引:3
K Taghzouti A Louilot J P Herman M Le Moal H Simon 《Behavioral and neural biology》1985,44(3):354-363
The effects of dopaminergic depletion of the nucleus accumbens was tested in various behavioral tasks such as alternation, spatial discrimination, and reversal learning, and in an extinction paradigm in a T maze. Animals with lesions showed impairment of spontaneous alternation behavior, disturbances in the acquisition of spatial discrimination, and great difficulty in reversing previously learned habits. In the extinction phase, experimental animals are unable to adjust their behavior, and continue to choose the previously reinforced arm of the T maze. It is suggested that the nucleus accumbens plays an important role in the transition of motivation into action, and that dopamine has a facilitatory influence on the mediation of these processes. 相似文献
852.
To test the generality, across modality and across species, of a bidirectional effect of photic stimulation in infant rats found in previous experiments, two experiments examined the effects on heart rate (HR) of onset and offset of auditory stimulation in rats and of photic stimulation in guinea pigs. Experiment 1 demonstrated a unidirectional, decelerative response in rats 17 and 21 days of age to the onset and offset of a 1-kHz tone, at both low (80 dB) and high (100 dB) intensity levels and at 14 days to the onset of the high-intensity tone. Experiment 2 demonstrated that infant guinea pigs, which unlike infant rats are precocial and not nocturnal, responded to the offset but not to the onset of light, and that this response was decelerative. These results indicated a lack of generality of the bidirectional HR effect, and were discussed in terms of the orienting/defensive reflex distinction. 相似文献
853.
Aggressive behavior inhibition by serotonin and quipazine injected into the amygdala in the rat 总被引:1,自引:0,他引:1
The effects on aggressive behavior, open-field activity, and pain threshold of bilateral microinjections of serotonin (20 micrograms) and quipazine (20 micrograms), the direct serotonergic receptor agonist, into the cortico-medial amygdala were investigated in Wistar rats. Both drugs significantly prolonged the attack latency in isolated killer rats (predatory aggression model), and suppressed the incidence of aggressive postures/attacks in shock-induced fighting test (affective aggression). The only difference in the open-field behavior was the lower number of central square entries in drug-treated compared to saline-injected rats. None of the substances produced any significant change in jump threshold. It is concluded that stimulation of serotonin receptors within the amygdala produces inhibition of affective and muricidal behavior in isolated rats. The effect does not seem to be dependent on changes in general activity and pain sensitivity. 相似文献
854.
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857.
Classmate likeability, compromising skill, and temperament (n = 135) and after-school patterns of social interaction (n = 101) were examined for third through seventh grade children who were identified by a binomial probability model as popular, rejected, neglected, or average in the classroom setting. Significant effects were obtained for each type of score. Compared to the other social status groups, popular children were the best liked and rejected children were the least liked; neglected and average children fell between these two extremes. Popular children had higher compromising scores than either rejected or average children, and neglected children had higher scores than rejected children. Compared to average children, rejected children had higher attention and rhythmicity temperament scores. Finally, popular and average children had more neighborhood friends than either rejected or average children, and meglected children had more younger neighborhood friends than did average children. Results are discussed in terms of models of peer social status. 相似文献
858.
Sleep laboratory studies of patients complaining of insomnia have demonstrated discrepancies between subjective reports and electroencephalograph (EEG)-recorded measures. In our research studies on sleeping aids, 60% of the self-described poor sleepers who reported usual sleep latencies of at least 45 min did not meet the laboratory qualification criterion of a 30-min or longer sleep latency. To learn to predict who would qualify for our studies, we compared 30 laboratory-qualified poor sleepers (QPS) with 30 laboratory-disqualified poor sleepers (DPSs) on subjective report, mood, and all-night sleep laboratory variables. QPSs had significantly lower sleep efficiency and total sleep time in the laboratory, but these differences were due to the longer sleep latencies (50.7 +/- 27.8 min vs. 15.2 +/- 6.1 min) of the QPS group. QPSs and DPSs differed significantly in their morning estimates of their laboratory sleep latencies; as a group, QPSs gave an accurate estimate (51.6 +/- 27.8 min), but DPSs were significantly more likely to exaggerate their sleep latencies. Although we did not identify ways of predicting which poor sleepers would show sleep-onset insomnia in the sleep laboratory, we did find that, in this young, healthy population, there are poor sleepers who give an accurate report of a rather severe sleep-onset insomnia. 相似文献
859.
NORMAN A. SCOTT 《Journal of counseling and development : JCD》1985,64(4):272-273
Counseling prisoners involves multiple ethical and therapeutic choices and risks. Prison environments emphasize external control and security. Thus, work in such settings challenges the role of the counselor as a facilitator of client responsibility for independent decision making. 相似文献
860.
D DeJianne T R McGuire A Pruzan-Hotchkiss 《Journal of comparative psychology (Washington, D.C. : 1983)》1985,99(1):74-80
Food-deprived Drosophila melanogaster extend their proboscises following sucrose stimulation of the front tarsi (the proboscis extension reflex). Médioni and Vaysse (1975) reported that the inhibition of this response can be conditioned over trials if such proboscis extensions are punished by applying an aversive stimulus to the foreleg tarsi. In this study, Médioni and Vaysse's basic observations of conditioning were replicated, with a different strain of flies and a modified conditioning apparatus. 相似文献