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1.
Two stutterers, both recent college graduates, were subjected to regional cerebral blood flow measurements while attempting to read aloud. Each one received two measurements, one of which was under the influence of haloperidol, 3 mg daily. Both subjects showed improvement on medication, allowing a stuttering versus essentially no stuttering comparisons for each subject. Both subjects showed higher Broca's area flow in the right compared to the left hemisphere, during stuttering. Both showed higher Wernicke's area flow in the left compared to the right hemisphere, however, during stuttering. During reading aloud without stuttering, however, the Brocas's area flows were reversed, now showing a left hemisphere advantage. The results were interpreted as consistent with H. M. Sussman and P. F. MacNeilage's (1975, Neuropsychologia, 13, 19–26) proposal that stutterers exhibit conventional left cerebral dominance for speech reception, but inadequate left cerebral dominance for speech production.  相似文献   

2.
Two randomly assigned groups, N = 7 each, of neurologically normal patients were composed. One group, RM, had regional cerebral blood flow measurements during a recognition memory probe test; the other group, SC, had rCBF measurements during a semantic classification task, using the same stimulus and response features as the RM task. Thus, the groups differed only in the cognitive instruction they were executing. The RM group showed a significantly lower change from resting baseline to activation, in mean left hemisphere initial slope index, than did the SC group. The RM group, but not the SC group, showed a significant inverse correlation between occipital flow and accuracy of memory performance as indicated by d′. Correlations between age and hemispheric initial slope index, and between homologous left and right hemisphere sites, were also described. The results are considered to support an anatomical basis for the distinction between episodic and semantic memory and to suggest that occipital flow may diminish with accurate memory performance because of an upstream demand of blood in the medial temporal lobes.  相似文献   

3.
A case of remitted global amnesia, believed to have residual left medial temporal lobe damage, is tested by the same recognition memory paradigm used by Wood, Taylor, et al. in the previous paper. On two different testing occasions, once using an intentional and once an incidental memory procedure, the patient's right occipital flows were inversely correlated with memory accuracy and the values were very close to the regression line for 10 normals relating occipital flow to memory accuracy. The left occipital flows did not fit the regression line, however. The results were interpreted as consistent with the notion that occipital flow is inversely related to medial temporal lobe activation. Another surprising feature of this case is the unexpected persistence of amnesia for a period from about 5 to 10 years before her episode to about 2 weeks after the episode, with recovery of memory functioning for the period since that time.  相似文献   

4.
A college professor with a classical amnesic syndrome is described. He has a WAIS IQ of 130, but dramatic memory loss for episodes ranging from a few seconds ago all the way back to portions of his childhood. The amnesia was of sudden onset, 2 years prior to the current memory tests and regional cerebral blood flow measurements. The etiology is believed, though not conclusively proven, to be medial thalamic infarction. rCBF measurements were taken on six separate occasions, four resting baseline, one memory activation, using the previous procedure of Wood, Taylor, et al., and one carbon dioxide activation. The resting baseline showed extremely low flows throughout the cortex, with some hyperfrontal response on the first baseline. With CO2 activation, however, there was brisk, uniform reactivity, with all sites showing increased flow. This suggested that there were no prominent areas of impaired vasomotor control or probable ischemic damage in the cortical surface. During memory activation, there was also a generalized increase in flow, especially in the frontal areas. This was in sharp contrast to the pattern for normals, described by Wood, Taylor, et al., which shows a slight overall decrease in flow from baseline to memory activation. The results are interpreted in light of Talland's proposal that the amnesic syndrome reflects an arousal failure, with premature closure and shutdown of memory processing, especially at retrieval. Here the arousal failure is interpreted as an inadequate restriction or focusing of cortical activation, with resulting pathologically diffuse flow increases.  相似文献   

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Theories and research on the topics of attraction, conformity, and imitation support the view that the relational stimulus arising from being imitated serves a reinforcing function. To examine this possibility, 48 preschool children performed a task in which some neutral stimuli were repeatedly associated with an adult's matching the behavior of the subject, and other neutral stimuli were associated with the same adult's mismatching the behavior of the subject. Preference for the stimuli associated with being matched was greater at the end of training than earlier, and the overall preference for the matched stimuli exceeded chance. The results are considered in terms of the thesis that similarity arising from being imitated served a reinforcing function and the thesis that response strategies were adopted by the children.  相似文献   

9.
Cerebral laterality was examined for third-, fourth-, and fifth-grade deaf and hearing subjects. The experimental task involved the processing of word and picture stimuli presented singly to the right and left visual hemifields. The analyses indicated the deaf children were faster than the hearing children in overall processing efficiency, and that they performed differently in regard to hemispheric lateralization. The deaf children processed the stimuli more efficiently in the right hemisphere, while the hearing children demonstrated a left-hemisphere proficiency. This finding is discussed in terms of the hypothesis that cerebral lateralization is influenced by auditory processing.  相似文献   

10.
Many writers implicate perceptions of the opportunity structure in the labor market as essential components of the formation, stability, and enactment of socioeconomic achievement attitudes. These perceptions of opportunity are thought to be observed structural constraints and reflective of more than just pure motivation. Previous attempts at measuring “perceived opportunity” have no consistent approach or conceptualization. This study evaluates a 10-item scale of perceived occupational opportunity in an attempt to overcome many of these problems. Using panel data covering the period of career decision making and labor force entry (adolescence to young adulthood), the internal reliability and construct validity of the linear composite are assessed. The scale's external validity is then further explored within the context of a structural equation model linking perceived opportunity to social origins, adolescent career plans, and early socioeconomic attainments.  相似文献   

11.
Previous research has shown that intermittent punishment of a response increases its persistence to continuous punishment and that intermittent punishment training in one situation produces persistence to continuous punishment in other situations. Experiment 1 showed that as long as the instrumental response and punishing stimulus were held constant from intermittent to continuous punishment marked differences between these situations had no decremental effect on persistence. Experiment 2 showed that intermittent punishment training of one response resulted in substantial persistence to continuous punishment of a different and apparently incompatible response and that such response change had no more than a marginal effect on persistence. The results were seen as requiring some revision to the traditional conditioning-model interpretation of persistence to punishment.  相似文献   

12.
In previous studies using the Preschool Racial Attitude Measure (PRAM) and other measurement procedures, preschool children have displayed a tendency to evaluate light-skinned (Euro-American) persons more positively than dark-skinned (Afro-American) persons. Both Euro- and Afro-American children demonstrate this pro-Euro/anti-Afro (E+A?) bias, though it is less pronounced among Afro children.Two experiments designed to modify this racial bias are reported. The first study involved 39 Euro- and Afro-American preschool children and employed operant learning principles to modify E+A? bias via a teaching machine procedure which provided reinforcement for pro-Afro/anti-Euro responses. Following training, the children showed a reduction in E+A? bias on a test procedure not associated with the training. Follow-up testing of 30 of the children approximately 1 yr after the posttest revealed a tendency for the pro-Euro bias to be partially reestablished. The second study involved 70 Euro-American kindergarten children and was concerned with the modification of E+A? bias via a classroom curriculum procedure and the possible influence of the race of the teacher associated with the curriculum. The experimental curriculum, designed to develop positive associations to dark-skinned persons and to the colors black and brown, was shown to have no effect on E+A? bias, nor was race of teacher a variable of significance. Possible explantations for the findings of both experiments were discussed.  相似文献   

13.
The present study investigated cortical alertness in Ss displaying fast and slow habituation of the evoked skin conductance response (SCR). From Sokolov's statement (Perception and the conditioned reflex, 1963, Pergamon) that the final stage of habituation is sleep, it was predicted that during monotonous stimulation, Ss displaying rapid habituation of the evoked SCR would show a more rapid decline in cortical alertness than Ss displaying slow habituation. Quantified EEG and electrodermal measures of cortical alertness were obtained from fast and slow habituation groups tested under conditions of either repetitive auditory stimulation or reduced sensory input. The results indicated that 8–13 Hz EEG abundance declined more rapidly in fast than in the slow habituation groups under both conditions of monotonous stimulation. No differences were obtained for the lower EEG frequencies (4–8 and 2–4 Hz) or for tonic electrodermal measures.  相似文献   

14.
Two moderately retarded boys, ages 11 and 12 yr, who resided in an inpatient unit for emotionally disturbed children, were treated for deficits in social skills. The deficits included physical gestures, facial mannerisms, eye contact, words spoken, and intonation and content of speech. The treatment package consisted of instructions, performance feedback, social reinforcement, modeling, and role-playing. The effects of the treatment in developing appropriate social performance were evaluated in separate multiple-baseline designs across behaviors for each child. The training improved social skills and brought children up to or beyond the level of normal control subjects who were the same age and gender.  相似文献   

15.
There is a parallel between our tendency to infer the attitudes of an individual on the basis of his or her behavior, regardless of the external constraints (Jones & Harris, 1967; Ross, 1977), and our tendency to infer the attitudes of a group on the basis of the group's decision, regardless of the group decision rule. The present research focuses on this latter process. What we term the group attribution error consists of the tendency to assume that group decisions reflect members' attitudes. This assumption can be erroneous because group decision rules, in addition to members' attitudes, can influence group decisions. In Experiment 1, members of a community in which a water conservation law was or was not instituted were assumed to have correspondent attitudes, regardless of how the community decision was made. In Experiments 2 and 3, subjects inferred a greater correspondence between out-group decisions and out-group attitudes than between an in-group decision and in-group attitudes. The fourth experiment found that subjects committed the group attribution error because they attended as much to the outcome of a recall election as to the actual proportion of voters for and against the recall. Finally, Experiment 5 showed that subjects' inferences of jury members' attitudes were influenced not only by the final jury vote but also by the actual decision, which was determined by the vote plus the decision rule by which the jury was bound. The results are related to previous research on the fundamental attribution error, stereotyping, and polarized appraisals of out-groups.  相似文献   

16.
A convenient paper-and-pencil measure of acting or role-playing ability was constructed, validated, and compared to a variety of theoretically and methodologically similar and dissimilar scales, including a specially designed improvisational situations test. Results indicate that the new scale provides both a reliable and valid screening device for the study of role-playing ability.  相似文献   

17.
This review examines the cerebral control of musical behaviors. In clinical populations, impairment of related musical and linguistic functions, such as reading, writing, articulation, time sense, and prosody, implies the likely role of the language hemisphere in music. Similarly, for both clinical and normal populations, an investigation of mental abilities common to music and language points to left hemisphere control for certain aspects of temporal order, duration, simultaneity, rhythm, effector motor control, and categorical perception. While clinical studies have revealed deficits in various kinds of music capabilities with both left and right cerebral lesions, normal subjects similarly demonstrate varying degrees of asymmetry for components of music emphasizing pitch, harmony, timbre, intensity, and rhythm. Since differential laterality effects are apparent as a function of subjects' training or adopted strategies, the way musical information is processed may be an important determinant of hemispheric mediation. One hemisphere should not be regarded as “dominant” for music, but rather each interacts with the other, operating according to its own specialization.  相似文献   

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This review describes methodological improvements of the 133Xe-inhalation technique for measurement of regional cerebral blood flow (rCBF) comprising correction routines both for scattered radiation from air passages and for remaining activity from previous measurements, as well as a new index of curve fit exactness. Measurements in normals are described showing new characteristics of the resting flow pattern and localized flow changes during activation with a variety of mental tasks. Our clinical applications in psychiatry are reviewed demonstrating the ability of the rCBF technique for differential diagnosis of dementia, for the evaluation of treatment by drugs, ECT, or psychosurgery, as well as for following, cases of toxic influence. The paper finally discusses the potentials as well as the limitations and artifacts of the technique.  相似文献   

20.
Three studies examined the role of the perceived typicalness of an out-group member on her effectiveness in improving evaluations of her group. Subjects were students at two adjacent colleges. In the first study they interacted with a member of the out-group college. The interaction was either pleasant or unpleasant, and the contact person either confirmed or disconfirmed several stereotypes of the out-group (typicalness manipulation). Subjects evaluated the out-group most favorably when they interacted with the typical-pleasant member of the out-group. The second study demonstrated that contact with a highly typical member is not beneficial if her typicalness is based on stereotypes that reflect negatively on the subject's in-group. Several explanations of the typicalness findings were considered in a third study. Support was found for the hypothesis that the more typical member is perceived to be more predictive of the personality and actions of other out-group members.  相似文献   

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