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1.
Regional cerebral blood flow (rCBF) was studied by single photon emission computerized tomography (SPECT) of inhaled xenon-133 in six normal volunteers during various language, articulatory, and control conditions. Language production increased rCBF in predominantly left-sided cortical and subcortical areas. The involved regions were anatomically related to a left frontal area (Broca's), to both caudate nuclei, to a left thalamic/pallidal area, and bilaterally in retrorolandic areas. The failure to demonstrate lateralized retrorolandic activity is thought to reflect the complexity of the tasks.  相似文献   

2.
It has been suggested that intermittent reinforcement may be of value in reducing the rate of relapse in bedwetting conditioning therapy. An experiment was conducted with 30 enuretic boys to examine acquisition and extinction parameters of continuous (100%), intermittent (70% variable ratio), and “placebo” (0%) reinforcement schedules. Reinforced trials were administered as in the typical Mowrer conditioning procedure. Non-reinforced trials were achieved by means of a time delay with the subsequent alarm being activated in the parent's room rather than in the child's room. These procedures required the development of a new conditioning device which could be programmed to automatically administer the desired schedule of reinforcement. The results of the field investigation revealed that continuous reinforcement (CR) and intermittent reinforcement (IR) groups attained acquisition in approximately the same number of trials and with essentially the same success rate. Relapse rate was significantly greater in the CR group than in the IR group. The placebo group showed no improvement over the 6 weeks of treatment. The results of this study may be interpreted as supporting the tenet that relapse can be viewed and treated as an extinction of the acquired response.  相似文献   

3.
28 dextral males participated in a within-subjects experiment which tasted for the effects of question type (verbal versus spatial) and experimenter-position (in front of or behind the subject) on direction of conjugate lateral eye movements (LEMs) and bilateral differences in skin conductance responses (SCRs). Question dependent asymmetries were observed for LEM direction but not for SCR magnitude. Experimenter-position had no significant effect. The results for LEM direction are consistent with the hypothesis linking eye movements to the left or right with activation of the cerebral hemisphere contralateral to the direction of gaze. The results for SCR magnitude, given certain assumptions, can be reconciled with a hemispheric model of contralateral excitatory control of that system.  相似文献   

4.
Towards a model of stress and human performance   总被引:19,自引:0,他引:19  
An outline is presented of a model that aims to relate energetical and structural mechanisms of human information processing and to incorporate an interactionally defined stress notion in performance research. The first section summarizes objections to unidimensional notions of arousal and stress. It is concluded that further progress requires the analysis of joint cognitive-energetical processing structures. In the second section two current performance models - in terms of linear stages and resources - are briefly reviewed. Despite a number of problems and objections, it is decided to base the model upon linear stage notions of information processing. This is further elaborated in the third section. In accord with Pribram and McGuinness (1975) three energetical supply systems are proposed which are selectively related to specific cognitive processing mechanisms. Stress is defined as a state of imbalance in the energetical supply which is difficult to restore or to compensate. The final section is devoted to the discussion of some lines of evidence and to suggestions for future research.  相似文献   

5.

At the center of medical morality is the healing relationship. It is defined by three phenomena: the fact of illness, the act of profession, and the act of medicine. The first puts the patient in a vulnerable and dependent position; it results in an unequal relationship. The second implies a promise to help. The third involves those actions that will lead to a medically competent healing decision. But it must also be good for the patient in the fullest possible sense. The physician cannot fully heal without giving the patient an understanding of alternatives such that he or she can freely arrive—together with the physician—at a decision in keeping with his or her personal morality and values. In today's pluralistic society, universal agreement on moral issues between physicians and patients is no longer possible. Nevertheless, a reconstruction of professional ethics based on a new appreciation of what makes for a true healing relationship between patient and physician is both possible and necessary.  相似文献   

6.
It is suggested the concept of “stability” in the study of work values has at least three facets: (1) hierarchical stability, (2) response pattern stability, and (3) factor stability. These three facets are investigated using a sample of 165 Australian students, assessed using a work values list initially in Grade 12 and then 212 years later during which time all had engaged in full-time tertiary study. Of the 13 work values assessed only independence and intellectual stimulation increased in importance and surroundings decreased. Canonical correlation analysis revealed four significant response patterns which indicated that the same work value may sometimes be stable or changeable in combination with other work values. It was also found using factor analysis that two rotated principal components appeared stable over time. They were identified as an Intellectual Concern factor and People Concern factor. An Extrinsic Concern factor for subjects as high school students was found to differentiate into a Status/Power Concern factor and a Co-workers Concern factor by the time of the second assessment. A Freedom Concern factor found in the Grade 12 assessment was not discovered until 212 years later. The results confirm the need for further theoretical and methodological refinement of the notion of stability in the study of work values.  相似文献   

7.

Much attention has been given to determining whether an adolescent patient has the capacity to consent to research. This study explores the factors that influence adolescents' decisions to participate in a research study about youth violence and to determine positive or negative feelings elicited by being a research subject. The majority of subjects perceived their decision to participate to be free of coercion, and few felt badly about having participated. However, adolescents who were alone in the room during the assent process were more likely to report that they chose freely to be a research subject. This study may influence the ways physicians communicate with adolescent patients around research assent within a clinical care environment.  相似文献   

8.
The paper considers the issues, raised by Koriat et al. (1973), of the consistency and reliability of measures of habituation currently used in personality research. It is argued that the problem of reliability is not as serious as Koriat et al. proposed and that specificity of measures of habituation is a theoretical rather than a methodological problem. It is proposed that ambiguity in the literature on the personality correlates of habituation is more likely to be due to the failure to consider the effects of stimulus conditions on habituation than to the problems of reliability and specificity.  相似文献   

9.
The purpose of the present study was to examine the effectiveness of a self-control package in enhancing temporal generality of a parent training program. Sixteen mothers and their clinic-referred noncompliant children were assigned to either a parent training alone group, or a parent training plus self-control group. All mother-child dyads were treated individually by teaching the mother to reward compliance and other prosocial behavior, and to use time-out for noncompliance. In addition, mothers who also received self-control training learned to self-monitor their use of their new parenting skills and to reinforce themselves for use of the skill during a 2 month follow-up period. Assessment consisted of four home observations by independent observers prior to treatment, after treatment, and at a 2 month follow-up. The data indicated that the children in the parent training plus self-control group were significantly more compliant and less deviant at the 2 month follow-up than the children in the parent training alone group. Parental behavior did not differ between the two groups at the follow-up.  相似文献   

10.
Vocalizations are preceded by slow EEG waves over inferior frontal scalp regions, but some controversy exists as to whether these slow potentials are left-lateralized as a function of speech. In this study both speech and non-speech vocalizations were studied, under conditions of repetitive and variable production. Averaged responses over the speech musculature, including the temporalis, masseter, orbicularis oris, and mylohyoid muscles, as well as the eyes and tongue, were calculated simultaneously with scalp EEG averages. The responses of the temporalis and masseter muscles, as well as that of the tongue, were correlated with EEG sites at specific latencies prior to speech, suggesting that no part of the inferior frontal EEG record was free from myogenic confounds. In addition, all significant EEG differences between speech and non-speech conditions were subsequently eliminated by covariance analysis, using selected muscle channels as covariates. Previous reports of asymmetrical “speech potentials” in the EEG probably reflected a combination of several myogenic confounds.  相似文献   

11.
Previous studies of the identification of rotated symbols have been restricted to either alphanumeric characters or symbols designed to be similar in complexity and type to alphanumerics. These researches have found identification response times to be independent of the magnitude of a symbol's angular displacement from a standard upright position, such findings being typically interpreted as supporting a feature extraction model of identification. In the present experiment complex Japanese characters were used to assess whether such a feature extraction interpretation could be generalized to identifying complex rotated symbols. Identification response times were also found to be constant across all non-standard orientations of the characters, supporting a feature extraction interpretation, but quicker times for standard cases suggested that some qualifications might be necessary.  相似文献   

12.
Nursery school children were presented with a simple miniature artificial language in one of three conditions. In the first, the stimuli to which the words referred contained an inherent lawful relationship and the language syntax reflected this relationship. In the second, the stimuli contained an inherent lawful relationship but the language syntax did not reflect this relationship. In the third, no lawful relationship existed among the stimuli to which the words referred so the language syntax imposed an arbitrary relationship among stimuli. Subjects in the first group were able to produce more correct utterances than those in the other two groups when the stimuli to which the words referred were not present, suggesting that some form of semantic mediation mechanism was being used. Evidence from novel constructions indicates that for both groups using stimuli containing an inherent lawful relation there were interactions between semantic learning mechanisms and syntax learning mechanisms.  相似文献   

13.
The specific impairment of performance on repetition tasks has classically been identified with conduction aphasia. It is argued that this impairment can be subdivided and a deficit in span performance distinguished from that of the reproduction of single words. An explanation of the span deficit in terms of auditory-verbal short-term memory is preferred to hypotheses involving disconnections or damage to order retention systems. It is shown that a short-term memory component is present in many patients previously classified as conduction aphasics.  相似文献   

14.
The presence of a target's unexpected change in behavior following an influence attempt was hypothesized to be a critical variable for attributing influence to a particular agent. Observers read a brief story in which an agent's intervention was followed by the target's compliance, noncompliance, or countercompliance to the request. The results indicated that influence was attributed to the agent in the conditions demonstrating change, i.e., compliance and countercompliance, regardless of the direction of that change. Additional findings indicated that influence attributed to an agent decreased if the target delayed final compliance with the intervention.  相似文献   

15.
The paper discusses the mathematical foundations of a technique of multidimensional scaling, generalizing Guttman scaling, in which the structure of the embedding space relies only on ordinal concepts. An empirical relation is represented as an intersection of a minimal number (called bidimension) of Guttman relations. Fairly complete results are given for the cases of bidimensions 1 and 2. In the general case, the main results are based on the equivalence between the bidimension and the dimension of a certain partial order. A characterization of the bidimension as the chromatic number of some hypergraph is also provided.  相似文献   

16.
Three analogue experiments examined flooding therapy. Experiment 1 showed that flooding was more effective than standardized desensitization in reducing snake phobia. Experiment 2 examined three different modes of presenting the feared stimuli in flooding: taped auditory presentation, pictorial presentation, and a combination of these two. An additional combination group were given a brief in vivo exposure to the feared object immediately after each of three treatment sessions. Both a behavioral test and subjective estimates of fear showed advantages for the combined group that had the in vivo exposure, although it appeared that auditory instructions to imagine interaction with the snake was the best method for presenting the feared stimuli. Experiment 3 compared the auditory imagined method with and without ‘aversive’ or ‘implosive’ scenes, and with either an immediate or a delayed in vivo exposure. The only procedure to produce marked effects was the one that omitted ‘aversive’ scenes and provided immediate post-treatment in vivo exposure.  相似文献   

17.
The purpose of this article is to present the results of a two-year project to evaluate the Precision Fluency Shaping Program (Webster, 1980) in a community speech and hearing center. Fifty stutterers participated in therapy. Results indicated that Precision Fluency Shaping was an effective therapy for the treatment of stuttering. In addition, stutterer's perception of their speech changed from pre to post therapy. Follow-up data are presented on 28 clients. Advantages of conducting Precision Fluency Shaping, meeting accountability standards, and procedures for collecting follow-up data are discussed.  相似文献   

18.
The comprehension of sentences with “because” or “if” was investigated in children aged 2;9–11;11. Imitation, comprehension (choosing one of two picture sequences to go with a sentence), recognition (judging sentences with connective or structure differences as heard before or not), and synonymy (judging equivalence of meaning in sentences with different connectives or structures) tasks were administered, along with logical ordering, reversibility, and classification tasks. Above-chance responding in the comprehension task occurred by age 8, and in recognition and synonymy by age 10. Cognitive performance predicted 28.4% of the variance in the linguistic scores and cognitive success was concurrent with or preceded linguistic success. Comprehension of “because” and “if” appears to develop gradually, and is related to the development of certain operative rules.  相似文献   

19.
Two hundred consecutively seen aphasics, 142 of them with infarcts, were examined by tests of fluency, comprehension, repetition, naming, and information content. The language scores were subjected to a minimum variance clustering algorithm separately for the total and for the infarct groups. The latter generated 10 clusters on a dendrogram. Attribute analysis of each cluster provided a clinically meaningful profile of language performance for these groups. The degree of correlation of most computer generated clusters with clinically recognized groups was high, and the homogeneity of some of the clusters is striking. An exception appears to be “conduction aphasia,” which is bimodally distributed. One of these clusters, with high fluency and low comprehension scores, was renamed “afferent conduction” aphasia, and the other, with lower fluency and higher comprehension, was renamed “efferent conduction” aphasia. The Principal Components Analysis was used to evaluate the discriminatory value of language characteristics, and the Nearest Neighbor Network Analysis was used to evaluate the significance of clustering. The dendrogram for all aphasics showed a less specific and less homogenous six clusters.  相似文献   

20.
The paper is concerned with the testing of psycholinguistic hypotheses by the use of deductive reasoning tasks. After reviewing some of the problems of interpretation which have arisen with particular reference to conditional rules, an experiment is presented which measures comprehension and verification latencies in addition to response frequencies in a truth table evaluation task.The experiment tests a psycholinguistic hypothesis concerning the different usage of the logically equivalent forms of sentence: If p then q and p only if q with respect to the temporal order of the events p and q. It is proposed that the former sentence is more natural when the event p precedes the event q in time, and the latter more natural when the opposite temporal relation holds.Although significant support is found for the hypothesis in the analysis of the latency data, it is only distinguished from an alternative explanation by detailed analysis of response frequencies, thus indicating the general usefulness of the paradigm adopted.  相似文献   

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