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931.
Recent reports in the literature suggest that anxious individuals show an attentional bias to mood-congruent information. Various investigators have hypothesized that such anxiety-based coding biases contribute to the maintenance of mood disorders. The present study sought to determine if attentional biases in anxious subjects extends to the perception of neutral, as opposed to affect-laden, stimuli. A procedure used to determine the locus of attention to foveal and peripheral visual events was used in combination with two inter-stimulus intervals, fixed and variable, to examine anxious and non-anxious subjects' attentional biases. Mood states were established by a well-validated musical induction procedure. The results revealed an attentional bias to foveal visual events in non-anxious subjects and an attenuated or reversed (peripheral) bias in anxious subjects. The clinical implications of these findings are discussed.  相似文献   
932.
Restrained eaters are rapidly habituating sensation seekers   总被引:1,自引:0,他引:1  
Several authors have pointed to similarities between eating disorders and addictive behaviors. In earlier studies, addicts were found to score high on the Sensation Seeking Scale (SSS) and to habituate rapidly to neutral stimuli. In this study, we found experimental support for an addiction model of eating disorders: restrained eaters also scored significantly higher on the Sensation Seeking Scale and also habituated significantly quicker to a series of neutral stimuli than unrestrained eaters. No clear evidence was found for the hypothesis that restrained eaters score lower on measurements of anxiety. It is hypothesized that rapid habituation promotes sensation seeking, which may be manifested in excessive consumption of either drugs or food. Restraint may be a strategy to prevent negative consequences of sensation seeking and excessive consumption. The model is related to earlier experimental findings.  相似文献   
933.
The purpose of this study was to compare our structured research-based version of marital therapy from a social learning perspective with a clinically flexible version of the same treatment where treatment plans were individually-based and there was no specific number of treatment sessions. Thirty distressed married couples were randomly assigned to one of these two treatments. Assessment of outcome was based on global marital satisfaction, spouse reports of functioning in specific areas, and direct observational measures of communication. At posttest there were no differences in efficacy between structured and flexible treatments, although both treatments led to significant improvements. At a 6-month follow-up couples treated with the structured format were more likely to have deteriorated and flexibly treated couples were more likely to have maintained their treatment gains.  相似文献   
934.
Thirty patients with phobia for blood, wounds and injuries were treated individually with applied tension, applied relaxation, or the combination of these two methods for 5, 9 and 10 sessions, respectively. They were assessed on self-report, behavioral and physiological measures before and after treatment, and at a 6-month follow-up. All groups improved significantly on 11/12 measures, and the improvements were maintained at follow-up. Applying stringent criteria, 73% of the patients were clinically improved at the end of treatment and 77% were so at follow-up. Despite a failure to find between-group differences, on many measures there was a trend favoring applied tension. Since this method is as effective as the other treatments in only half the time, applied tension should clinically be the treatment of choice for blood phobia.  相似文献   
935.
We presented 7- to 9-month-old infants with repetitions of three- or four-tone sequences characterized by a particular rhythmic structure. We then evaluated their detection of changes in rhythmic structure in the context of randomly presented variations in tempo (rate) and frequency. Infants successfully differentiated between three-tones sequences with 1, 2 (X XX) and 2, 1 (XX X) structure as well as four-tone sequences with 2, 2 (XX XX) and 3, 1 (XXX X) structure. In other tasks, they indicated their ability to discriminate between contrasting tempos in the context of frequency variations. We conclude, then, that infants can categorize auditory sequences on the basis of rhythm and also on the basis of tempo.  相似文献   
936.
Believability and syllogistic reasoning   总被引:4,自引:0,他引:4  
In this paper we investigate the locus of believability effects in syllogistic reasoning. We identify three points in the reasoning process at which such effects could occur: the initial interpretation of premises, the examination of alternative representations of them (in all of which any valid conclusion must be true), and the "filtering" of putative conclusions. The effect of beliefs at the first of these loci is well established. In this paper we report three experiments that examine whether beliefs have an effect at the other two loci. In experiments 1 and 2 subjects drew their own conclusions from syllogisms that suggested believable or unbelievable ones. In the third experiment they evaluated conclusions that were presented to them. The data show that beliefs both affect the examination of alternative models and act as a filter on putative conclusions. We conclude by showing how some types of problem and some problem contents make the existence of alternative models more obvious than others.  相似文献   
937.
Can we imagine how objects look from other viewpoints?   总被引:2,自引:0,他引:2  
Many psychologists who study cognition believe that perception achieves object-centered representations that make it possible to extract representations of how the object would appear from differing viewpoints. Others believe we can achieve representations of how an object would appear by a process of visualization or mental rotation. We report experiments in which the subject tries to imagine how three-dimensional novel wire objects would appear from positions other than the one they are in. Subjects are unable to perform this task unless they make use of strategies that circumvent the process of visualization. It is suggested that the linear increase in time required to succeed in mental rotation tasks as a function of the angular discrepancy between the figures compared is the result of increasing difficulty rather than of the time required for rotation.  相似文献   
938.
The field of infant perceptual development has relied heavily on the preferential-looking and habituation paradigms. Despite the obvious advantages of employing standardized methodologies, there is a need to study how perceptual variables give rise to and guide action beginning in the neonatal period. It is argued here that, in the first 5 months of life, it is important to distinguish reflexive patterns of movement from voluntary and cortically controlled patterns. Some criteria are defined. This paper describes three experiments which utilized movement counters to record developmental changes in the frequency and synchrony of limb movements in infants under 5 months. The results show that there is a general increase in frequency of limb movements from 1 to 5 months, but with a plateau or even a decrease in activity from the middle of the third month to the end of the fourth month. It was also demonstrated that synchrony scores (co-activation) for pairs of limbs showed significant increases from 1 month to 5 months. Finally, in all three experiments the presentation of an attractive toy resulted in suppression of activity. The results of the three experiments are interpreted to measure a gradual increase in cortically controlled movement patterns.  相似文献   
939.
The psychology of knights and knaves   总被引:2,自引:0,他引:2  
L J Rips 《Cognition》1989,31(2):85-116
Knight-knave brain teasers are about a realm in which some people, knights, tell only truths, whereas all others, knaves, tell only lies. For example, suppose person A says, "I am a knight and B is a knight," and person B says, "A is a knave." Is A a knight or a knave? Is B a knight or a knave? In a pilot study, we asked subjects to think aloud while solving problems like these. Their statements suggested that they were making assumptions about the knight/knave status of the characters and drawing deductive inferences from these assumptions to test their consistency. This encouraged us to model the process by means of a simulation based on an earlier natural-deduction theory of reasoning. The model contains a set of deduction rules in the form of productions and a working memory that holds a proof of the correct answer. The greater the number of steps (assumptions and inferences) in the proof, the greater the predicted difficulty of the puzzle. The experiments reported here confirmed this prediction by showing that subjects were more likely to make mistakes (Experiment 1) and take longer to solve (Experiment 2) puzzles associated with a larger number of proof steps.  相似文献   
940.
Neuronal models of cognitive functions   总被引:4,自引:0,他引:4  
J P Changeux  S Dehaene 《Cognition》1989,33(1-2):63-109
Understanding the neural bases of cognition has become a scientifically tractable problem, and neurally plausible models are proposed to establish a causal link between biological structure and cognitive function. To this end, levels of organization have to be defined within the functional architecture of neuronal systems. Transitions from any one of these interacting levels to the next are viewed in an evolutionary perspective. They are assumed to involve: (1) the production of multiple transient variations and (2) the selection of some of them by higher levels via the interaction with the outside world. The time-scale of these "evolutions" is expected to differ from one level to the other. In the course of development and in the adult this internal evolution is epigenetic and does not require alteration of the structure of the genome. A selective stabilization (and elimination) of synaptic connections by spontaneous and/or evoked activity in developing neuronal networks is postulated to contribute to the shaping of the adult connectivity within an envelope of genetically encoded forms. At a higher level, models of mental representations, as states of activity of defined populations of neurons, are discussed in terms of statistical physics, and their storage is viewed as a process of selection among variable and transient pre-representations. Theoretical models illustrate that cognitive functions such as short-term memory and handling of temporal sequences may be constrained by "microscopic" physical parameters. Finally, speculations are offered about plausible neuronal models and selectionist implementations of intentions.  相似文献   
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