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951.
A theory of visual interpolation in object perception   总被引:10,自引:0,他引:10  
We describe a new theory explaining the perception of partly occluded objects and illusory figures, from both static and kinematic information, in a unified framework. Three ideas guide our approach. First, perception of partly occluded objects, perception of illusory figures, and some other object perception phenomena derive from a single boundary interpolation process. These phenomena differ only in respects that are not part of the unit formation process, such as the depth placement of units formed. Second, unit formation from static and kinematic information can be treated in the same general framework. Third, spatial and spatiotemporal discontinuities in the boundaries of optically projected areas are fundamental to the unit formation process. Consistent with these ideas, we develop a detailed theory of unit formation that accounts for most cases of boundary perception in the absence of local physical specification. According to this theory, discontinuities in the first derivative of projected edges are initiating conditions for unit formation. A formal notion of relatability is defined, specifying which physically given edges leading into discontinuities can be connected to others by interpolated edges. Intuitively, relatability requires that two edges be connectable by a smooth, monotonic curve. The roots of the discontinuity and relatability notions in ecological constraints on object perception are discussed. Finally, we elaborate our approach by discussing related issues, some new phenomena, connections to other approaches, and issues for future research.  相似文献   
952.
The current study examined whether juvenile firesetting represents a unique syndrome or an advanced level of antisocial behavior. Thirty-six incarcerated juvenile delinquents, all of whom met criteria for a diagnosis of Conduct Disorder, served as subjects and were categorized into one of three groups: firesetters, non-firesetters but comparable to firesetters in number of conduct disorder symptoms, and non-firesetters who displayed fewer conduct disorder symptoms than the other two groups. Caregivers completed the Child Behavior Checklist on the youth to provide information about the severity and range of psychopathology. The results indicated that firesetters and non-firesetters who had a comparable number of symptoms did not differ from one another on the CBCL subscales of adolescent psychopathology but both differed from the group with fewer symptoms. These results suggest that firesetting does represent an advanced level of antisocial behavior, but that firesetting is not a unique syndrome, at least not in terms of caretakers' perceptions of the youths' problematic behavior. Implications for treatment of firesetters are presented.  相似文献   
953.
Tested predictions that assertiveness and social support would be significantly predictive of psychological adjustment. Furthermore, it was anticipated that assertiveness and certain types of social relationships would differentially interact to predict adjustment, since positive and negative effects of both variables have been noted in prior research. Trained raters interviewed 156 persons receiving either in-patient or out-patient care for cord injuries and administered measures of assertiveness, social support, depression and psychosocial impairment. Persons who reported a keen sense of responsibility for the welfare of another reported more depression and impairment. Persons reporting higher levels of support facilitating social integration and reassuring personal worth were less depressed. Several significant interactions between assertiveness and different social support relationships revealed beneficial and deleterious effects on depressive behavior and impairment secondary to the disability. Results are discussed as they advance theoretical understanding of the effects of assertiveness and social support. Implications for discriminate cue learning in assertion training for persons with physical disability are proposed.  相似文献   
954.
Cognitive therapy. A 30-year retrospective   总被引:6,自引:0,他引:6  
Several lines of investigation have evolved from the initial cognitive model of depression and other disorders. A large number of studies have tested the cognitive model using both clinical and laboratory-based strategies. In general, studies that most closely approximate the clinical conditions from which the theory was derived are supportive of the cognitive model of depression. Studies of anxiety and panic, although fewer, generally support the cognitive model of anxiety and panic. The application to the treatment of clinical problems has been promising and supports the concept of cognitive specificity. The cognitive therapy of depression has led to the utilization of specific cognitive strategies based on the specific conceptualizations of a given disorder to a wide variety of disorders. Study of abnormal reactions has also provided clues to the cognitive structure of normal reactions.  相似文献   
955.
Ideomotor theory is one variation of the general position that perception and motor action are related. According to this theory, a perceptual representation of the goal of a response must be generated prior to response initiation. Ideomotor theory can be extended by assuming that generation of this representation, which usually is required prior to motor action, is not needed if the stimulus itself corresponds to the response goal, that is, if the stimulus and response are ideomotor compatible. Because processing to generate the response representation is not needed with ideomotor compatibility, it should be possible to control two responses simultaneously without mutual interference if at least one stimulus-response relation is ideomotor compatible. Although supported in previous work involving discrete responses, this prediction of perfect time-sharing was found not to hold in the experiments reported here. These experiments, unlike those showing perfect time-sharing, involved continuous responses. We propose an alternative version of ideomotor compatibility, in which perfect time-sharing can occur if an integrated stimulus is provided to match the continuous and integrated response.  相似文献   
956.
Fathers' involvement in the routine healthcare of young children was investigated, and fathers' relative participation in two tasks, staying home with a sick child and taking the child to the doctor or dentist, was assessed. The relationships between fathers' involvement in healthcare and several other measures, including mothers' employment status, fathers' attitudes toward women's rights and roles, the amount of time fathers spent at work, and fathers' involvement in housework, were also examined. The subjects were 50 fathers of young children in intact, White, middle-class families. Both staying home with a sick child and taking a child to the doctor or dentist were usually performed by mothers, but when mothers were employed, fathers were significantly more involved, regardless of the child's sex. Staying home with a sick child and taking a child to the doctor or dentist were positively related to fathers' involvement in housework. Fathers' staying home with a sick child was significantly correlated with fewer hours at work and liberal attitudes toward women's rights and roles; these variables were not related to taking a child to the doctor or dentist. Positive correlations between fathers' involvement in housework and staying home with a sick child and taking a child to the doctor or dentist suggests that fathers' involvement in childcare is viewed as an aspect of family work.  相似文献   
957.
Personality and susceptibility to positive and negative emotional states   总被引:20,自引:0,他引:20  
Gray's (1981) theory suggests that extraverts and neurotics are differentially sensitive to stimuli that generate positive and negative affect, respectively. From this theory it was hypothesized that efficacy of a standard positive-affect induction would be more strongly related to extraversion than to neuroticism scores, whereas efficacy of a standard negative-affect induction would be more strongly related to neuroticism scores. Positive and negative affect was manipulated in a controlled setting, and the effectiveness of the mood induction was assessed using standard mood adjective rating scales. Results are consistent with the hypothesis that neurotic Ss (compared with stable Ss) show heightened emotional reactivity to the negative-mood induction, whereas extraverts (compared with intraverts) show heightened emotional reactivity to the positive-mood induction. Results corroborate and extend previous findings.  相似文献   
958.
Seven studies investigated the cognitive structure of social relationships exhibited in the patterns of substitutions that occur when people confuse a person with another. The studies investigated natural errors in which people called a familiar person by the wrong name, misremembered with whom they had interacted, or mistakenly directed an action at an inappropriate person. These studies tested the relational-models theory of A. P. Fiske (1990b, 1991) that people use 4 basic models for social relationships. All 7 studies provide support for the theory; Ss tend to confuse people with whom they interact in the same basic relationship mode. In addition, Ss confuse people of the same gender. Other factors (age, race, role term, similarity of names) generally have smaller, less reliable effects, indicating that the 4 elementary modes of relationships are among the most salient schemata in everyday social cognition.  相似文献   
959.
In a laboratory experiment, undergraduate subjects tested positive for an enzyme deficiency they believed to be a risk factor for pancreatic disorders. All Ss were tested with a confederate who received a positive or negative test result. For half the Ss, the confederate expressed a minimizing appraisal of the deficiency's seriousness. Although Ss' concern about the test result was significantly reduced by what the confederate said, behavioral intentions were determined by the confederate's diagnostic status. The effect of the confederate's diagnostic status on intentions was mediated by Ss' perceptions of the deficiency's prevalence. The results support Leventhal's self-regulation theory and demonstrate that the opinions and health characteristics of comparison others have differential effects on cognitive, emotional, and behavioral aspects of coping with a health threat.  相似文献   
960.
Two experiments were conducted using an autoshaping procedure with pigeons to examine whether dimensional stimulus control by a Pavlovian facilitator parallels the control established following operant discrimination training. Facilitation training consisted of the presentation of a black vertical line on a white background as the B stimulus in a feature-positive discrimination in which the A stimulus (white keylight) was followed by grain presentation only if preceded by B. In this way, B facilitates or sets the occasion for pecking at A. Subsequent testing for generalization along the line-orientation dimension produced decremental gradients when the facilitation paradigm incorporated an explicit feature-negative stimulus (B−). These results parallel the decremental control obtained following operant discrimination training and suggest that Pavlovian facilitators and instrumental discriminative stimuli are functionally equivalent.  相似文献   
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