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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.
The physical elevation corresponding to visually perceived eye level (VPEL) changes linearly with the pitch of a visual field. Deviations from true eye level average more than 0.5 times the angle of pitch over a 65 degrees pitch range. A visual field consisting of 2 dim, isolated vertical lines in darkness is more than 4/5 as effective as that of a complexly structured visual field; 2 horizontal lines have a small and inconsistent effect. Differences in influence on VPEL between pitched-from-vertical and horizontal lines were predicted from an analysis that extracted differences in retinal perspective resulting from changes in pitch. The Great Circle Model (GCM), based on a spherical approximation to the erect, stationary eye, predicts the present results and results of 8 other sets of experiments. The model treats the influence of a single line on VPEL as systematically related to the elevation of the intersection between the great circle containing the image of the line and the central vertical retinal meridian; generalized GCM combines visual inputs with inputs from the body-referenced mechanism and maps onto the central nervous system.  相似文献   
13.
A variety of abnormal sensory/motor behaviors associated with electrical discharges recorded from the bilateral brainstem were induced in adult WKY rats by mechanical (electrode implants) and DC electrical current stimulations and by acute and chronic administration of cocaine. The electrode implant implicated one side or the other of the reticular system of the brainstem but subjects were not incapacitated by the stimulations. Cocaine (40 mg/kg) was injected subcutaneously for an acute experiment and subsequent 20 mg/kg doses twice daily for 3 days in a chronic study. Cocaine generated more abnormal behaviors in the brainstem perturbation group, especially the electrically perturbated subjects. The abnormal behaviors were yawning, retrocollis, hyperactivity, hypersensitivity, "beating drum" behavior, squealing, head bobbing, circling, sniffing, abnormal posturing, and facial twitching. Shifts in the power frequency spectra of the discharge patterns were noted between quiet and pacing behavioral states. Hypersensitivity to various auditory, tactile, and visual stimulation was present and shifts in the brainstem ambient power spectral frequency occurred in response to tactile stimulation. These findings suggest that the brainstem generates and propagates pathological discharges that can be elicited by mechanical and DC electrical perturbation. Cocaine was found to activate the discharge system and thus induce abnormal behaviors that are generated at the discharge site and at distant sites to which the discharge propagates. Cognitive functions may also be involved since dopaminergic and serotonergic cellular elements at the brainstem level are also implicated.  相似文献   
14.
In two experiments, semantic facilitation and translation priming effects in Chinese-English bilingual speakers were demonstrated with a lexical decision task. A 300-msec stimulus-onset asynchrony (SOA) was used between display of the prime and the target item. Experiment 1 showed that subjects' lexical decision responses were facilitated to a greater extent when primed by a translation equivalent than a semantically related between-language word. In Experiment 2, we found that pictorial, between-language, and within-language primes produced comparable effects of semantic facilitation. These results are in line with the hypothesis that lexical items in different languages and pictures are processed by means of an amodal conceptual system.  相似文献   
15.
The effects of right and left hemiparkinsonism on prosody   总被引:2,自引:0,他引:2  
Recent studies show right hemisphere dominance in the mediation of emotional prosody and left hemisphere contribution to linguistic prosody in patients with cortical injury. The present study investigated emotional and linguistic functions of prosody as well as facial and musical processing in 21 patients with lateralized subcortical disease. Fourteen right hemiparkinsonians (RPD) and 7 left hemiparkinsonians (LPD) were compared to 17 normal controls (NC). Patients were impaired on receptive and expressive tests of emotional and linguistic prosody. Patients were also selectively impaired on emotional processing of facial stimuli and in the musical processing of pitch and tonal memory, though not timber. These findings suggest that monotone speech reported in PD is of multimodal origins and may involve dysfunction in neural centers involved in emotional and linguistic processing. There were no differences between RPD and LPD groups in the pattern of deficits, suggesting bilateral involvement in emotional processing at the subcortical level.  相似文献   
16.
Neuropsychological functioning in hemiparkinsonism   总被引:3,自引:0,他引:3  
A standardized neuropsychological battery including measures of intellectual cognitive, memory, attention-concentration, language, abstraction and mental flexibility, and sensory and motor functions was administered to 21 hemiparkinsonian patients (14 with right side and 7 with left side symptoms) and 17 controls matched for age and education. Patients were impaired in all functions except sensory. For motor functions, impairment was ipsilateral to the side of symptoms. For cognitive functions, right side symptoms were associated with verbal deficits whereas left side symptoms were associated with spatial deficits. Thus, a pattern of neuropsychological deficits consistent with the lateralization of motor symptoms may appear in the early stages of the disease.  相似文献   
17.
广州大学生对衣服款式及颜色爱好特点的实验研究   总被引:1,自引:0,他引:1  
本文采用心理物理学的等级排列法,用男女各16种服式及27种颜色布样做材料,随机抽取广州市五所大学一年级学生男女各30名为被试,对被试的服式爱好和颜色爱好特点进行实验研究,结果表明:(1)单纯对布样颜色爱好的顺序与对特定服式的颜色爱好顺序不一样、衣服款式不同,喜欢配搭的颜色的爱好等级顺序也不同。(2)当前男女大学生都喜欢活泼大方、文雅、有朝气的服装款式,而不喜欢过时的、古旧的服式。(3)从颜色明度来看,大学生喜欢明度大的(反射率Y大的)颜色,不喜欢明度小的(反射率Y小的)颜色。其颜色爱好变化趋势是从明度大的颜色向明度小的颜色方向变化。  相似文献   
18.
Two experiments examined appetitive differential conditioning of the rabbit’s jaw movement response (JMR) in a two-phase procedure. The first phase entailed reinforced training with one conditioned stimulus (CS+), and the second phase involved intermixed presentations of CS+ and an unreinforced stimulus (CS?). In Experiment 1, CS+ was a 600-Hz tone, and CS-was either a 660-,1,000-, or 2,100-Hz tone. In Experiment 2, the magnitude of the water unconditioned stimulus (US) paired with CS+ was either 1, 3, or 9 ml. The experiments revealed that 1) the level of responding to CS-rose for several days and then declined over the remainder of training; 2) the physical similarity between CS+ and CS?directly affected the level of responding to CS?but had no discernable effect on the level of responding to CS+ ; and 3) US magnitude positively affected the level of responding to CS + and, to a lesser extent, CS?. The results are discussed in terms of their implications for Spence’s gradient interaction theory and Pavlov’s external inhibition hypothesis.  相似文献   
19.
Effects of presentation complexity on rapid-sequential reading   总被引:1,自引:0,他引:1  
  相似文献   
20.
Two factors that were thought to promote or inhibit schema-based or stereotypic responding in impression formation were examined in two experiments. Subjects were asked to provide evaluations of artwork supposedly painted by either mentally retarded or nonretarded children. Based on previous research, it was assumed that subjects would expect relatively poor quality artwork from retarded children, which would he consistent with a negative schema that they maintain for this group. It was also predicted that this negative schema would result in cursory examinations and unfavorable evaluations of the retarded artists' artwork, but only when the evaluative conditions were conducive to schematic responding. Specifically, the schema effect was predicted to occur when the artwork was of poor quality and subjects were instructed to provide an overall evaluation of the painting rather than an assessment of its specific characteristics. No derogation was expected when these factors were not present. Results supported these hypotheses. Additional analyses indicated that subjects were conducting a cursory search of the target stimuli when conditions favored schema-based responding.  相似文献   
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