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851.
Subjects searched for a chromatic target among coloured background items. With low target-background chromatic similarity, response latencies remained uniformly short whether the target was present or not and whether the items were chromatically homogeneous or not. Latencies increased with increases in target-background similarity and were longest with heterogeneous backgrounds, with which the effects of trial type also became manifest. We employed Treisman's model of visual search to account for these findings. In particular, we suggest that similarity increases forced a shift from a preattentive to an attentive search, the latter being importantly shaped by the background's level of chromatic variance.  相似文献   
852.
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   
853.
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   
854.
B G Hanson 《Family process》1989,28(3):281-289
This article presents some general theoretical concepts that can be used to consider processes of reality construction in interpersonal contexts. I developed a model of family context that taps affective dimensions of reality construction and used this model to explore these processes as highlighted by the labeling of symptoms of senile dementia. Ethnographic observations of 45 families with aged members were used to sketch a dichotomous typology of family-context patterns that promote symptom identification versus patterns that do not. The model suggests that the categorization of behavior as symptomatic or normal in context may be related to the extent to which reality construction processes are shared among members.  相似文献   
855.
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   
856.
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   
857.
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   
858.
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   
859.
679 Egyptian boys and 696 girls completed the Junior Eysenck Personality Questionnaire, translated into Arabic. Factor comparisons were moderately high for extraversion and social desirability but weak for neuroticism and psychoticism. Suitable item substitution produced a scoring key resulting in adequate reliabilities with the exception of a somewhat low reliability for the boys on extraversion and low reliabilities on psychoticism for both sexes. Sex differences on means of the dimensions were as usual, boys scoring higher than girls on extraversion and psychoticism, but lower on neuroticism and social desirability. Moreover, on comparing Egyptian with English means, using scales of items in common only, the English boys and girls scored higher than their Egyptian counterparts on extraversion but significantly lower on social desirability. British boys scored higher on psychoticism than did Egyptian boys but British girls scored lower than Egyptian girls.  相似文献   
860.
What changes take place in request production between the ages of 6 and 7? In other words, what do children ask for, whom do they ask, and how do they formulate their requests? Twenty children, native French-speaking children divided into 2 age groups (6 and 7 year old) were asked to complete 2-character comic-strip stories where the hero either made a request to a friend or an enemy. Requests were for action or for information. In both age groups, children tend to use the direct form and embedded imperatives more often when the hero addressed a friend. Hints were employed more frequently when addressing an enemy. Requests for action were expressed primarily in both groups through direct requests, embedded imperatives and hints, whereas requests for information tended to take form of question directives. Surprisingly, 6-year-olds produced more indirect requests than the 7-year-olds, and particularly produced more question directives and hints. Reformulations in the 6-year-old group consisted of repeating the first request, whereas the 7-year-old group evidenced clear ability to produce a variety of reformulations. These results form the basis for a psychological interpretation of earlier findings. Discussion enters on children's ability to link linguistic form of request to the social features of production situation.  相似文献   
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