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301.
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
302.
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
303.
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
304.
Violence and the systemic view: the problem of power 总被引:1,自引:0,他引:1
P F Dell 《Family process》1989,28(1):1-14
Violence is a strikingly lineal concept that is difficult to address from a systemic perspective. Bateson's epistemological disqualification of the concept of power is often understood to imply a corresponding systemic disqualification of the concept of violence. This position is examined in light of recent feminist criticism. It is argued that (a) violence and power belong essentially to the domain of human experience and (b) human experience cannot be invalidated by theory. Accordingly, it is suggested that the (appropriate) invalidation of power and violence in the domain of systemic explanation should probably be understood both as a deliberate choice that necessarily follows from adopting a systemic perspective, and as a fundamental limitation of that perspective. In neither case, however, should the systemic view be considered to be a valid disqualification of the human experience of violence and power. 相似文献
305.
A.C. Mundy-Castle D.J. Wilson P.S. Sibanda J.S. Sibanda 《International journal of psychology》1989,24(1-5):539-546
The cognitive effects of LOGO were examined among 11–12-year-old black and white Zimbabwean girls and boys. Fifty-two experimental group children were exposed to a BBC LOGO programme with a screen turtle. Forty-one control group children received no exposure to computers at school. Pre-tests on four WISC-R subscales were held in January, 1987 and post-tests on the same four WISC-R subscales were held in November/December, 1987. The data were analyzed with multivariate analysis of covariance, using pre-test scores as the covariate. The results suggested that children in the experimental group did better on the WISC-R Arithmetic scale and that black girls exposed to LOGO showed particular gains in spatial reasoning, as measured by the WISC-R Block Design scale. It is concluded that LOGO appears to facilitate cognitive growth. Methodological limitations of the present study are discussed and suggestions for future research are presented. 相似文献
306.
Relations of sociotropic and autonomous personality characteristics to specific symptoms in depressed patients 总被引:2,自引:0,他引:2
A number of writers have suggested that two sets of personality characteristics are associated both with vulnerabilities to depression in response to different classes of events and with different clinical presentations of depression. The present study examined the relations between levels of sociotropic and autonomous personality characteristics and specific, theoretically derived clusters of symptoms in 80 unipolar depressed patients. As was predicted, sociotropy was related to the cluster of symptoms associated with the concept of anxious-reactive depression and was unrelated to the autonomous symptoms cluster. In contrast, the predicted relations of autonomous personality characteristics and symptoms were not found. These results support the idea that the symptom picture in depression may be related to personality characteristics, but they also suggest that the measurement of autonomy may require revision. 相似文献
307.
Nonclinical panic in college students: an investigation of prevalence and symptomatology 总被引:2,自引:0,他引:2
This article presents data on the prevalence and symptomatology of panic attacks and panic disorder (PD) in a large nonclinical sample (n = 2,375) of college students. Results showed that approximately 12% of the sample had experienced at least one unexpected panic attack and that 2.36% met DSM-III-R criteria for panic disorder. Although there were no sex differences in overall panic attack prevalence, men reported significantly more panic-related worry than women, and women reported a higher panic frequency than men. Compared to subjects who met DSM-III-R criteria for PD, infrequent panickers presented with fewer panic symptoms, fewer panic episodes, less panic-related worry, lower anxiety sensitivity, and less panic-related avoidance. Moreover, compared with PD subjects, the infrequent panickers were much less likely to report fears of dying, going insane, and derealization during a panic attack. The findings provide preliminary support for the role of anxious apprehension as a psychological vulnerability factor in the pathogenesis of panic disorder. 相似文献
308.
309.
The Nuremberg trials focused worldwide attention on 22 Nazi war criminals. Rorschach Inkblot tests were administered to these Nazi leaders in an attempt to understand the Nazi personality. Past studies which have described and interpreted these Rorschach records have made at least two types of errors in their analyses. One is that of overinterpretation and excessive inference. A second common error has been the failure to detect meaningful distinctions between protocols that represent significant differences in personality style. This latter error is shown in repeated attempts to group all Nazi protocols into one distinct "Nazi personality." This investigation attempted to quantify the analysis of these Nazi Rorschach records, specifically those Nazi leaders who were sentenced to life imprisonment or execution for their war crimes against humanity, by utilizing Exner's (1985a) standardized Comprehensive Scoring System as well as computerized objective interpretation software based on the Exner system (1986). This modern analysis of the Rorschach records demonstrates that the Nazi war criminals cannot be grouped together into one specific mental disorder that would adequately characterize these diverse individuals. The varying degrees of psychopathology of the Nazi leaders are illustrated by analyses of individual Rorschach protocols. 相似文献
310.
From rarity to evaluative extremity: effects of prevalence information on evaluations of positive and negative characteristics 总被引:1,自引:0,他引:1
Experiments showed a scarcity principle in evaluative judgments such that the identical characteristic is evaluated more extremely the lower its perceived prevalence. In Study 1, Ss evaluated a fictitious medical condition that was described as either beneficial or detrimental to health and as occurring in either 30% or in one half of 1% of a test population. The condition was evaluated more extremely--as as a more positive health asset or a more negative health liability--in the low-prevalence than in the high-prevalence conditions. Study 2 demonstrated the same effect in self-evaluations and with a different manipulation of perceived prevalence. Ss were told that they actually had the fictitious medical condition, that it was either beneficial or detrimental to their health, and either that they were the only 1 of 5 Ss who had it or that 4 of the 5 did. Low-prevalence Ss exhibited more extreme evaluative, affective, and behavioral reactions to the medical condition than did high-prevalence Ss. The origins and validity of the scarcity principle are discussed, as are its implications for uniqueness theory, reactance theory, and social evaluation theories. 相似文献