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911.
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
912.
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
913.
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
914.
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
915.
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
916.
Neuronal models of cognitive functions 总被引:4,自引:0,他引:4
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
917.
Prior discussion of hypothesizing as a session "guideline" has not fully clarified the derivation of hypotheses. Reviewing relevant philosophy of science literature, the authors develop the notions of evidence and evidence-gathering in systemic family therapy. The authors claim evidence-gathering and hypothesizing are interdependent, reciprocal elements of scientific understanding. The structure of evidence is described along with practical and qualitative rules for collecting and using evidence. This model is applied to a case example illustrating the logic of clinical process. Implications are discussed for family therapy training and supervision. 相似文献
918.
What do celibates consider the adaptive and maladaptive aspects of their celibate religious lifestyle? What role has celibacy played in understanding the differences between those who persevere and those who choose to resign from celibate religious life and/or ordained ministry? Using data from extensive interviews, this exploratory study begins to focus some of the perceived effects of celibacy upon personal development for both those who persevere in celibate religious life and those who resign. 相似文献
919.
Dependency, self-criticism, and depressive attributional style 总被引:1,自引:0,他引:1
Dependency and self-criticism have been proposed as independent factors in depression. Investigated whether depressive individuals characterized by dependency and self-criticism, respectively, differ with regard to internality of causal attributions for negative events. Sixty psychiatric outpatients completed the Depressive Experiences Questionnaire, the Beck Depression Inventory, the semantic differential, and the Attributional Style Questionnaire. Dependency and self-criticism correlated positively with internality and with each other (p less than .0001). Findings did not support the specificity of dependency and self-criticism as subtypes of depression. 相似文献
920.
Self-discrepancies in clinical depression and social phobia: cognitive structures that underlie emotional disorders? 总被引:5,自引:0,他引:5
T J Strauman 《Journal of abnormal psychology》1989,98(1):14-22
Previous research indicates that self-discrepancies are cognitive structures that can induce emotional discomfort. The present study compared clinically depressed and social phobic subjects (plus controls) to determine whether different self-discrepancies were associated with the two disorders. In Part 1, it was shown that the depressives possessed the greatest discrepancy between their actual and ideal/own self-states, whereas the social phobics possessed the greatest discrepancy between their actual and ought/other self-states. In a later, ostensibly unrelated study, subjects responded verbally to questions about other people while their mood changes, skin conductance responses, and verbalizations were recorded. The questions included attributes from the subject's ideal and ought self-states that were mismatches with attributes from his or her actual self, as well as mismatch attributes from other subjects. Priming with self-referential mismatches induced momentary syndromes of dejection or agitation (depending on the type of mismatch). The depressives and social phobics showed the greatest increases in dejection and agitation, respectively, according to their dominant self-discrepancy. The results suggest that specific cognitive structures may underlie clinical depression and anxiety. 相似文献