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921.
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   
922.
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   
923.
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   
924.
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   
925.
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   
926.
There is a power to touch, and a magic. Some call it mystery. The purpose of this paper is to reflect on the various meanings and uses of touch, particularly within the context of relationship and helping. There will be no attempt to formulate a protocol for touch or to lay claim to a definitive meaning for touch. Reflection about touch may instead clarify some of its meanings and dynamics while encouraging care providers to embrace the experience of helping-through-touch. This paper supports a considered use of empathie touch because of its power and its ability to embody care.  相似文献   
927.
Loneliness as part of the human condition is first explored from an experiential-philosophical perspective. A biblical survey suggests loneliness is normative to the faith experience and may portray a more realistic religiosity. Desert imagery in Scripture indicates a strong association among solitude, spiritual development, and potential dangers of spiritual deception. God's not yet-ness-itself a cause of existential loneliness—is paradoxically the way in which communion with God functions in the here and now. The creative use of solitude may enhance social, psychological, and spiritual well-being, and provide a way to theologize about personal isolation and disorientation.He is also editor of theHarding Journal of Religion and Psychiatry.  相似文献   
928.
The differences between hostility scores on projective and objective tests as a function of listening to aggressive or nonaggressive rock music were studied. While taking the Thematic Apperception Test (Cards 1, 3BM, 4, 9BM, and 10) and the Buss-Durkee (1957) Hostility Scale, subjects (N = 90) randomly assigned to one of three groups listened to a rock song with (a) nonaggressive music and nonaggressive lyrics, (b) aggressive music and nonaggressive lyrics, or (c) aggressive music and aggressive lyrics. TAT stories were scored for aggressive content according to Hafner and Kaplan's (1960) hostility rating scale. Hostility scores did not differ between groups. The findings are congruent with other investigators' reports that subjects do not pay attention to rock lyrics. Previous findings that music affects the emotional quality of TAT stories and hostility scores on the Buss-Durkee scale were not supported.  相似文献   
929.
A common error made by behavior genetics researchers is breeding two lines for differences in central arousal rather than for a specific behavioral feature. Two lines of rats (Riley, Freed, & Lester, 1976) were selectively bred for locomotor impairment in response to a subhypnotic dose (1.5 g/kg) of ethanol. These lines (designated "most affected" and "least affected") were compared in a variety of tests and showed differences in a number of phenotypic traits in addition to locomotor impairment to ethanol. The published findings have been interpreted in light of a hypothesis suggesting adventitiously selected differences in central arousal between the two lines. This interpretation showed that their usefulness as animal models of alcoholism is seriously compromised.  相似文献   
930.
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   
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