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891.
Recent research suggests that anxiety is not a single, unified reaction to perceived threat, but rather a cluster of interrelated factors whose relationships to performance change as the individual progresses from one test event to another. This study investigated the presumed linkages between traitlike predispositions to perceive threat and achievement performance, as mediated by statelike anxiety arousal on a longitudinal basis (Perceived Threat Anxiety Arousal Impaired Performance). College students were administered self-report questionnaire measures during a preenrollment period, after the first two midterms, and following the last two midterms in a general psychology course. Four performance measures and 26 motivational indicators were fitted to a 10-factor latent model using LISREL model-fitting techniques. Path-analytic interpretations of this structural model provided little evidence for the commonly held view that traitlike threat perceptions mediate performance via statelike anxiety reactions. Far more promising, theoretically, are those influences on test performance stemming from the self-attributional, cognitive domain. Overall, the findings support a recent reinterpretation of achievement anxiety as stemming from the disruptive effects of diminished ability perceptions (and hence, impaired personal worth), rather than from the interfering influence of diffused emotional arousalper se. 相似文献
892.
Recent findings indicate that post-training glucose injections can modulate memory storage for inhibitory (passive) avoidance training. Experiment I extended these findings to determine whether glucose, like other memory modulating treatments, enhances memory storage when administered after training with low footshock and impairs memory storage after high footshock training. In Experiment I, male Sprague-Dawley rats were trained in a one-trial inhibitory avoidance task using either a brief footshock (0.5 mA, 0.7 s) or slightly more intense footshock kept on until escape (0.7 mA, mean escape latency = 3.4 s). Immediately after training, each rat received a subcutaneous injection of glucose (100 mg/kg). When tested for retention performance 24 h later, the glucose-injected animals exhibited enhanced retention performance for low footshock training and impaired retention for high footshock training. Experiment II determined whether pretreatment with adrenergic antagonists blocked the effects of glucose on memory. Pretreatment with the alpha- or beta-adrenergic receptor antagonists, phenoxybenzamine, or propranolol, respectively, had no effect on acquisition or retention in animals trained with the brief footshock and did not affect glucose facilitation of that memory. In animals trained to escape footshock, phenoxybenzamine did not attenuate the amnesia produced by glucose. Propranolol-pretreated animals had impaired retention whether or not they received post-training amnestic injections of glucose; glucose had no effect on retention in these amnestic animals. These findings add further support to the view that glucose release after training and treatment may represent a physiological response subsequent to epinephrine release in modulating memory storage processing. 相似文献
893.
Initial environment influences amphetamine-induced stereotypy: subsequently environment change has little effect 总被引:1,自引:0,他引:1
Saline-treated and amphetamine-treated (7 mg/kg, ip, immediate) male rats from a Sprague-Dawley substrain were observed in two test environments designed to elicit different investigative responses in normal rats. Snout contact with the substrate was generated by placing the rat in a small enclosed cage. Absence of snout contact was induced by placement of the rat on a square elevated platform. Detailed ethological records were kept of locomotion, rearing, sitting, grooming, gnawing, and sleeping throughout the 90-min session. Amphetamine-treated rats incorporated environmentally contingent bodily postures into their forms of stereotyped behavior. The postures were characteristic of those evinced initially by the saline-treated rats in the same test environment. The control rats showed appropriate changes in their investigative behavior when the apparatus was changed at 10 and at 30 min postinjection. The amphetamine-treated rats, however, were completely unresponsive to such changes at 30 min and only partially so at 10 min postinjection. It was concluded that there is a temporal gradient of decreasing readiness to modify repetitive behavior after a single, large dose of amphetamine. 相似文献
894.
J. Douglas Rodick Scott W. Henggeler Cindy L. Hanson 《Journal of abnormal child psychology》1986,14(1):77-87
Two basic assumptions of the Circumplex Model of family systems were evaluated: (1) Healthy families evidence balanced degrees of cohesion and adaptability, whereas problem families evidence extreme degrees, and (2) families with balanced degrees of cohesion and adaptability possess more positive communication skills than families with extreme degrees. Subjects were 58 mother-son dyads from father-absent families. In 29 of the families the adolescent was a juvenile offender, while in the remaining families there was no history of arrest or psychiatric referral. The dyads completed the Family Adaptability and Cohesion Scales (FACES) and an unrevealed differences interaction task. FACES was highly proficient at differentiating delinquent from nondelinquent families. Moreover, in families with balanced degrees of cohesion and adaptability, the mothers' communication was significantly more supportive and explicit, and the dyads evidenced significantly greater warmth and affection than dyads with extreme degrees.This research was supported by funding to the Department of Psychology at Memphis State University granted through the Centers of Excellence Program of the State of Tennessee. We thank the staff of the Memphis-Metro Youth Diversion Project for their consideration and assistance. 相似文献
895.
Sustained attention in children at risk for schizophrenia: Findings with two visual continuous performance tests in a new sample 总被引:1,自引:0,他引:1
J. Rutschmann Barbara Comblatt L. Erlenmeyer-Kimling 《Journal of abnormal child psychology》1986,14(3):365-385
In partial replication of an earlier study, 35 children at high risk for schizophrenia, 25 children at high risk for affective disorder, and 53 normal control children from a new sample of 7- to 12-year-old subjects were tested with two new visual continuous performance tests. Response levels and intrasubject variability were analyzed separately. Multivariate analyses on factor scores derived from response levels indicate that "groups" is a significant predictor for a factor reflecting discriminability (or sensitivity) for the more difficult of these tests but not for the less difficult one, and that high risk for schizophrenia is associated with lower performance. Factor scores and multiple regression analyses were used to dichotomize subjects as to whether or not they are low performance outliers. A significantly larger proportion of subjects from the high risk for schizophrenia group than from the control groups were low performance outliers. Among subjects that developed psychopathology in adolescence, subjects at high risk for schizophrenia were more likely to have contributed low performance outliers early during childhood. 相似文献
896.
897.
898.
Access to spoken language and the acquisition of orthographic structure: Evidence from deaf readers 总被引:1,自引:0,他引:1
Vicki L. Hanson 《The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology》1986,38(2):193-212
Sensitivity to two types of orthographic structure was investigated: linguistically based orthographic regularity and summed single letter positional frequency. Deaf college students were found to make use of positional frequency information no less than hearing college students; however, the extent to which they made use of orthographic regularities in word recognition was related to their speech production skills. In one task, subjects were presented nonword letter strings for short durations, each followed by a masking stimulus and a target letter. They were asked to indicate whether or not the target had been present in the letter string. It was found that the accuracy of deaf subjects with good speech, like that of hearing subjects, was considerably greater for orthographically regular than irregular strings. In contrast, the accuracy of deaf subjects with poor speech was much less related to orthographic regularity. In a second task, in which subjects made judgements about how word-like various letter strings appeared, the judgements of the hearing subjects were more influenced by regularity than those of deaf subjects with poor speech. These results are discussed in terms of how expertise in speech relates to appreciation of orthographic regularity. 相似文献
899.
T O Nelson R J Leonesio R S Landwehr L Narens 《Journal of experimental psychology. Learning, memory, and cognition》1986,12(2):279-287
Distinctions are drawn between different predictors of an individual's memory performance, with emphasis on the notion of privileged access to idiosyncratic knowledge. Research is reported in which undergraduates attempted to recall the answers to general-information questions, then made feeling-of-knowing judgments on nonrecalled items, and subsequently had a criterion test (relearning, perceptual identification, or one of two versions of recognition). For predicting an individual's criterion performance, the individual's own feeling-of-knowing predictions were intermediate between two kinds of normative predictions: The individual's feeling-of-knowing predictions were more accurate than predictions derived from normative feeling-of-knowing ratings but were less accurate than predictions derived from base-rate item difficulty (normative probabilities of correct recall). Subsidiary analyses showed that factors other than unreliability are responsible for the partial inaccuracy of the individual's feeling of knowing. Ramifications are discussed for possible ways to improve the accuracy of an individual's feeling-of-knowing predictions. 相似文献
900.
Cognitive, motivational, social, and environmental influences on children's food choices 总被引:2,自引:0,他引:2
This study tested the applicability of a cognitive-motivational model of health behavior to children's food choices. A sample of 107 elementary schoolchildren provided ratings of 15 foods in terms of possible choice criteria (e.g., how tasty or healthful specific foods were) and social or environmental influences (e.g., whether foods were eaten by friends or were easy to get). Several measures of food consumption were taken, and cognitive-developmental level was assessed. Within-person correlations were calculated between food choices and each choice criterion and social/environmental factor. These "correlational indices" of influences on food choice subsequently were used to identify five distinct subgroups in the sample. Children at the operational level of cognitive development tended to be in one of three groups characterized by health orientation in food choice, taste orientation, or multiple-motive orientation. Dietary quality was poorest in the taste-oriented group. Children at the preoperational level tended to have one of two undifferentiated patterns of values across the correlational indices. Results provide evidence of: the viability of cognitive-motivational models to explain children's food choices, the promise of within-person research methodology, and the potential for enhanced health behavior-change programs by use of population segmentation and tailored interventions. 相似文献