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11.
大鼠作业成绩与脑内亮氨酸脑啡肽含量变化的相关性研究   总被引:1,自引:0,他引:1  
本工作采用穿梭式电击回避反应法和脑啡肽的放射免疫测定法,分析比较了大鼠作业成绩与脑内壳氨酸脑啡肽(Leu-enkephalin,LEK)含量的关系,在本实验条件下,观察到作业成绩不良组纹状体内LEK含量显著高于成绩优良组和对照组,并由实验证明,它们之间的差异不是由于在实验中接受电击的次数或电击总量不同造成的。这一结果提示,内源性亮氨酸脑啡肽可能参与记忆获得的调制。  相似文献   
12.
This research was designed to investigate development and behavioral mediation in lines of ICR mice that have been selectively bred for aggressive behavior. General behavioral reactivity and behavioral immobility have been implicated as potential mediators by prior analyses of preattack interactions. To evaluate the separate roles of these dispositions, the emergence of attacks in genetically selected lines was tracked for 11 years by three levels of analysis: over successive generations, over development, and over dyadic interactions. Convergent outcomes were observed in all three levels with respect to two findings: (a) Robust line differences were obtained in attack behaviors, and (b) strong associations were found between line differences in attacks and line differences in behavioral immobility. Conversely, all three levels of analysis indicated a weak and inconsistent association between line differences in attacks and measures of social and nonsocial reactivity.  相似文献   
13.
This research was undertaken to demonstrate, with correlational evidence, that presenting the rod-and-frame test (RIT) with either limited (tachistoscopic) or unlimited (Oltman’s, 1968, portable RFT) exposure time does not significantly affect the ranking of subjects. The underlying hypothesis is that the intersubject variability of performance on the portable RFT is due essentially to differences in sensitivity to the optostatic vection that appears automatically and almost immediately. Results of the tachistoscopic test show that the effect of angular size of the stimulus is similar to that described in the literature for unlimited time situations, and that subjects’ ranking is very similar regardless of the exposure time (W = .80). However, although a difference is observed between the means of low and high achievers in both types of RFT, intraindividual intertask homogeneity (correlation coefficient) is not verified in each of these subgroups. From these results, one can distinguish two processes in the RFT: the first, vections, has to do with the subject’s postural orientation and seems to playa great role in organizing interindividual differences. The second process, a more cognitive one, has a less striking effect and has to do with the selection of reference frames in perceptual organization.  相似文献   
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S Brédart  T Valentine 《Cognition》1992,45(3):187-223
Functional models of face recognition and speech production have developed separately. However, naming a familiar face is, of course, an act of speech production. In this paper we propose a revision of Bruce and Young's (1986) model of face processing, which incorporates two features of Levelt's (1989) model of speech production. In particular, the proposed model includes two stages of lexical access for names and monitoring of face naming based on a "perceptual loop". Two predictions were derived from the perceptual loop hypothesis of speech monitoring: (1) naming errors in which a (correct) rare surname is erroneously replaced by a common surname should occur more frequently than the reverse substitution (the error asymmetry effect); (2) naming errors in which a common surname is articulated are more likely to be repaired than errors which result in articulation of a rare surname (the error-repairing effect). Both predictions were supported by an analysis of face naming errors in a laboratory face naming task. In a further experiment we considered the possibility that the effects of surname frequency observed in face naming errors could be explained by the frequency sensitivity of lexical access in speech production. However, no effect of the frequency of the surname of the faces used in the previous experiment was found on face naming latencies. Therefore, it is concluded that the perceptual loop hypothesis provides the more parsimonious account of the entire pattern of the results.  相似文献   
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繁殖群中婴幼川金丝猴社会关系发展的个案研究   总被引:7,自引:0,他引:7  
使用瞬时取样法,对繁殖笼内出生的两只婴幼川金丝猴进行连续22个月的行为记录。结果表明,川金丝猴婴猴断乳大约在19—20月龄;断乳表现为母婴之间矛盾冲突的过程;群内其他雌性对初生婴儿表现出明显的抢婴、护婴和育婴行为;父亲对婴幼猴表现出接纳和容忍的态度;婴儿在断乳前是群内全体成员保护和爱护的对象,以后开始进入社会关系网,受到成年个体的责备,但很轻微;雌性幼猴在32月龄时尚未被记录到对群内成员表现威胁、蜷缩和匍伏等行为模式。  相似文献   
18.
Summary Many studies have shown that in a simple reaction-time (RT) task a non-informative leading cue decreases RT to a subsequent target presented in the same region as the cue. This facilitation lasts about 150 ms; it is then replaced by a sustained inhibition. Experiment 1 tests the hypothesis that the initial facilitation is due to motor, rather than perceptual, processes by using choice RT. Facilitation is greater and lasts longer in choice than in simple tasks, thus supporting the hypothesis. Experiment 2 shows that facilitation occurs even when the subject actively orients his or her attention away from the cue.  相似文献   
19.
Human analog tests of object permanence were administered to various breeds of adult dogs (Canis familiaris). Experiment 1 showed that the performance of terriers, sporting, and working dogs did not differ. Dogs succeeded in solving invisible displacement problems, but performance was lower than in visible displacement tests. Familiarity with the task had some influence because invisible displacement tests were more successful if they were preceded by visible displacement tests. In Experiment 2, odor cues from the target object and the hiding screens were available or were masked. Results confirmed that success was lower in invisible than in visible displacement tests and that these problems were solved on the basis of representation of visual information rather than on the basis of olfactory cues or of local rule learning. Dogs are compared with other species that display Stage 6 object permanence.  相似文献   
20.
Evidence for central nervous system, and more particularly cortical, etiology of anorexia nervosa is reviewed. Topics covered are neuropsychiatric comorbidity, inheritance patterns, the neurobiology of body-image disturbance and of the eating function, perinatal and alcoholic insult to the brain, neurochemical and neuroelectric disturbance, anatomic and metabolic brain imaging, and neuropsychological impairment. It is concluded that there is indeed an important neuropsychological etiological dimension to anorexia nervosa. The profile most frequently associated with anorexia nervosa is right posterior hypometabolism, followed by right anterior hypermetabolism, both associated with right-sided abnormal electroencephalogram spiking. It is also proposed that bulimia consists of a positive neurological subtype and that restricting anorexia represents a negative neurological subtype. Priorities for further research into anorexia nervosa are specified to include twin adoption studies, brain electrical topography studies, postmortem histological studies, and experimentally inspired neuropsychological studies.  相似文献   
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