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921.
Because young children have poorer auditory temporal resolution than older children, they ought to have, according to the inverse relation between temporal and frequency resolution, narrower auditory filters than older children. Therefore, the auditory filters of two 6-year-olds, two 10-year-olds, and two adults were measured by having them detect a 400-ms sinusoid (500, 1000, or 3000 Hz) centered in a spectral notch in a band of noise. The signal power for 71% correct was determined as a function of notch width with the two-alternative, forced-choice procedure. The principal results showed a significant decrease in signal power with age and a significant interaction between age and notch width. The best-fitting parameters of a model of the auditory filter showed that the filter was significantly wider for the 6-year-olds than for the 10-year-olds or the adults.  相似文献   
922.
Pigeon's observational learning of successive visual discrimination was studied using within-subject comparisons of data from three experimental conditions. Two pairs of discriminative stimuli were used; each bird was exposed to two of the three experimental conditions, with different pairs of stimuli used in a given bird's two conditions. In one condition, observers were exposed to visual discriminative stimuli only. In a second condition, subjects were exposed to a randomly alternating sequence of two stimuli where the one that would subsequently be used as S+ was paired with the operation of the grain magazine. In a third experimental condition, subjects were exposed to the performance of a conspecific in the operant discrimination procedure. After exposures to conspecific performances, there was facilitation of discriminative learning, relative to that which followed exposures to stimulus and reinforcement sequences or exposures to stimulus sequences alone. Exposure to stimulus and food-delivery sequences enhanced performance relative to exposure to stimulus sequences alone. The differential effects of these three types of exposure were not attributable to order effects or to task difficulty; rather, they clearly were due to the type of exposure.  相似文献   
923.
The matching law applies to wagtails' foraging in the wild   总被引:2,自引:2,他引:0       下载免费PDF全文
Field data concerning the time budgets and foraging success of pied wagtails (Motacilla alba yarrelli, Gould) are reanalyzed. It is found that the data are well described by the generalized matching law, with a marked bias towards spending time on the territory. In this case matching is not the result of maximizing reward rate, but it remains possible that it results from an allocation of time that maximizes survival.  相似文献   
924.
Previous research has shown that when pigeons are required to peck each of two keys four times in any order for reinforcement, stereotyped response sequences develop, though they are not required by the task. However, despite this stereotypy, sequences are not automatized. They require sufficient attention that sequence performance is disrupted by a concurrent, delayed matching-to-sample task. In the present experiments, pigeons were required to execute response sequences and delayed matching-to-sample concurrently. Experiment 1 showed that the matching task disrupts sequence performance even when the matching sample stimuli do not have to be processed concurrently with sequence execution. The presence of sample stimuli during sequence execution seems to command attention even if the sample stimuli are also available for processing when sequences are not being executed. Experiment 2 used the directed forgetting technique to show that pigeons do seem able to ignore sample stimuli if they are given information that tells them they will not be required to remember those stimuli later. Together, the experiments suggest attentional mechanisms in the pigeon that are not quite involuntary.  相似文献   
925.
The Social Relations Model: An integrative method for personality research   总被引:1,自引:0,他引:1  
As outlined by Snyder and Ickes (1985), the study of personality can be undertaken using one of three research approaches dispositional, situational, and interactive We show how the Social Relations Model provides an integrative method to estimate simultaneously dispositional, situational, and interactive effects Reviewed are component approaches to the study of personality The Social Relations Model is shown to be a component model (a special case of generalizability theory) applied in a social interaction context In the model, dispositional, situational, and interactive effects are termed actor, partner, and relationship effects, respectively The Social Relations Model can be used to answer a number of important issues in personality research The model can be used to assess reliability, measure the validity of self-ratings, and validate self-report inventories The model requires special designs in winch each person interacts with multiple partners Empirical examples are presented in which social anxiety, sex role inventories, and self-disclosure are studied  相似文献   
926.
An interactional approach to the study of personality and emotion   总被引:1,自引:0,他引:1  
The purpose of the present study was to examine the relation between personality and emotional feelings within ecologically valid settings Nineteen subjects rated their emotions in a wide variety of work, recreation, social, and alone situations sampled over a 30-day period They were also administered the Personality Research Form and the Eysenck Personality Questionnaire Although theoretically predictable relations were found between certain personality traits and specific emotions averaged across situations, it was not until we distinguished chosen from imposed situations that the most meaningful results were obtained Both temperament and nontemperament personality traits were found to be related to specific emotions Implications of the present findings for research on situation selection and the status of personality traits are discussed  相似文献   
927.
The relation of Type A behavior to IQ, academic achievement, and several clinically relevant dimensions of behavior in children was assessed in 873 fourth, fifth, and sixth graders by means of the Matthews Youth Test for Health (MYTH), the Cognitive Abilities Test (CAT), the Iowa Tests of Basic Skills (ITED), and the teachers' form of the Missouri Children's Behavior Checklist (MCBC-T). The MYTH and its competitiveness and impatience-aggression subscales were found to be differentially related to academic achievement and to account for a small but significant portion of the variance in achievement not accounted for by IQ. The subscales of the MYTH were found to be highly correlated with several clinically familiar dimensions of children's behavior. The significance of these findings for the construct validity of the MYTH is discussed.  相似文献   
928.
Self-report measures of Type A personality receive wide research usage despite mounting evidence that they are poor predictors of coronary heart disease. It was proposed that the limited prediction results in part from the failure to restrict measurement to only those Type A characteristics that are demonstrably related to excessive stress. The first study in this article reports a factor analysis of all items on the Jenkins Activity Survey (JAS), the most popular Type A questionnaire, along with 25 stress symptoms. Self-ratings were obtained from both male and female college students. Only one stress-related factor emerged including 12 JAS items out of 44. These were relevant to (a) hard-driving and competitive, (b) time-urgent, and (c) hostile/irritated characteristics. Study 2 reports correlations of +.50 and +.43 between the stress-relevant JAS items and stress for new samples of female and male college students. Study 3 considers the broader personality correlates of scores on the stress-relevant Type A items and reports markedly different patterns for male and female college students. Predicted correlations were found on new samples between these personality correlates, considered as scales, and stress-relevant Type A scores and stress.  相似文献   
929.
One of the most necessarily sensitive areas of pastoral care is dealing with perinatal death. This case study grows from a need for care providers to understand better the feelings of a mother in the loss of her baby. This particular exploration evolved from a taped interview with the writer's aunt (now in her seventies) and her dealings with the multiple losses she experienced over fifty years ago. Her conversation in the interview gives credibility to many coping skills that we endeavor to teach today and that she developed for herself out of a need to survive....it was as if the birds would never sing again.-Aunt Grace  相似文献   
930.
In this study, we investigated the factorial structure of the Manifest Anxiety Scale (MAS) among American, counseling graduate students (N = 227). The MAS was administered across transsituational and transtemporal conditions. The following four factors were yielded following orthogonal rotation: General Worries, Physiological Correlates of Anxiety, Distractibility, and Embarrassment. These four factors, however, explained less than one quarter of the common variance extracted. Following a comparison with previous factor analytic studies of the MAS, we discuss factors possibly contributing to the discrepant findings, with particular attention to the MAS's item content and psychometric properties and the nature of the population used.  相似文献   
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