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971.
972.
Previous studies of infants’ ability to integrate and to utilize relative motion as information for form in the absence of structural cues have primarily involved motions that are uniform in rate, direction, and path within the form to be constructed. In the present study, we examined infants’ ability to integrate relative motion information from motions that are nonuniform along these dimensions, and from this integrative process to construct a coherently rotating two-dimensional form. Infants’ ability to integrate nonuniform motion was measured with regard to their ability to discriminate the rotating form from a noncoherent control display containing the same absolute motions. The results showed that discrimination of the coherent and incoherent displays was not demonstrated until 7 months of age. Two additional experiments were conducted to rule out the possibility that this discrimination was based on the detection of local regions of coherence, rather than the perception of the global rotating form. In both experiments, the results did not support discrimination based exclusively on local cues alone. From the combined results of all three experiments, we conclude that infants demonstrate the capacity to integrate the information contained within nonuniform trajectories into a coherent structure by 7 months of age.  相似文献   
973.
Three experiments establish the size-weight illusion as a primarily haptic phenomenon, despite its having been more traditionally considered an example of vision influencing haptic processing. Experiment 1 documents, across a broad range of stimulus weights and volumes, the existence of a purely haptic size-weight illusion, equal in strength to the traditional illusion. Experiment 2 demonstrates that haptic volume cues are both sufficient and necessary-for a full-strength illusion. In contrast, visual volume cues are merely sufficient, and produce a relatively weaker effect. Experiment 3 establishes that congenitally blind subjects experience an effect as powerful as that Of blindfolded sighted observers, thus demonstrating that visual imagery is also unnecessary for a robust size-weight illusion. The results are discussed in terms of their implications for both sensory and cognitive theories of the size-weight illusion. Applications of this work to a human factors design and to sensor-based systems for robotic manipulation are also briefly considered.  相似文献   
974.
The concept of systemic quantization of behavior was used to study the interaction between dominant motivation and reinforcement on brain neurons. Feeding and escape were used as experimental models. Results showed that feeding and escape motivations are based on the mechanisms of ascending activating influences of lateral or ventromedial hypothalamic centers, respectively, on cortical neurons. Feeding and escape motivations evoked by electrical stimulation of hypothalamus, or the ones occurring naturally, modify the responses of single neurons of sensorimotor and insular cortex to sensory stimuli, to microiontophoretic application of neurotransmitters and neuropeptides, and especially to reinforcement. Dominant motivations are reflected in the burst-like activity and in a specific pattern of interpulse intervals of single units in various brain structures. Reinforcement transforms this activity into a regular pattern and also changes the neuronal responses of hypothalamic feeding and escape centers, to electrical stimulation and to microiontophoretic application of oligopeptides. Specific patterns of the unit responses to conditioned stimuli in the course of consecutive reinforcement was determined. After several instances of reinforcement, especially after repetitive reinforcement, the brain neurons influenced by the dominant motivation begin to produce specific protein molecules that are important for organization of an appropriate type of behavior. This process can be blocked by protein synthesis inhibitors.  相似文献   
975.
When a deaf child is born to hearing parents, a grieving process is initiated in the parents. Unresolved grieving over their child's deafness often makes it difficult for hearing parents to accept the importance of signing, thus increasing the child's problems — further source of grief for these parents. Clinical illustrations are provided of (1) the reciprocal relationship between disruption of the mourning process and disturbance of communication between family members, and (2) the transmission of the dysfunctional relationship between hearing parents and deaf children to the subsequent relationship between the deaf children, when they reach adulthood, and their hearing children.  相似文献   
976.
977.
In this paper, we demonstrate that the study of prayer facilitates understanding of the deeply personal object related nature of religious experience. Within prayer, individuals enter the transitional sphere and meet their God representation. Both conscious and unconscious aspects of prayer can be made available through the use of a projective test developed by the authors, known as STARR: Spiritual Themes and Religious Responses test. The data obtained suggest the usefulness of Winnicottian concepts of transitional phenomena, playing, communicating, and capacity to be alone as a contemporary psychoanalytic framework for interpreting religious experience.  相似文献   
978.
A difficult case in psychotherapy can be defined in many ways. This study proposes a model for that definition, in which three domains (patient characteristics, case characteristics, and therapist characteristics) are considered to impact on that definition. A total of 264 professionals received a questionnaire to assess the relative importance of a series of variables within and across these domains. Wilcoxon Matched-Pairs Signed-Ranks tests indicated that patient characteristics were considered more important than therapist or case characteristics in defining a difficult case. Case characteristics were considered more important than therapist characteristics. Pearson correlations, however, suggested that the three domains in the model are related. Correlations (for years of experience) and Kruskal-Wallis one-way ANOVA for ranks (for professions) also indicated that participants were able to identify variables within domains as important in that definition regardless of years of experience or professions. Across domains, the most important variables included the motivation of the client (a patient characteristic), dropout/attrition and multiple diagnoses (case characteristics), and the degree of therapist-client racial similarity (a therapist characteristic).  相似文献   
979.
980.
ABSTRACT Previous research has indicated that extraversion and neuroticism are substantially affected both by genotype and environment. This study assesses genetic and environmental influences on the other three components of the five-factor model of personality: Openness to Experience, Agreeableness, and Conscientiousness. An abbreviated version of the NEO Personality Inventory (NEO-PI) was administered to 82 pairs of identical twins and 171 pairs of fraternal twins reared apart and 132 pairs of identical twins and 167 pairs of fraternal twins reared together. Estimates of genetic and environmental effects for Openness and Conscientiousness were similar to those found in other studies of personality: Genetic influence was substantial and there was little evidence of shared rearing environment. Results for Agreeableness were different: Genetic influence accounted for only 12% of the variance and shared rearing environment accounted for 21% of the variance. Few significant gender or age differences for genetic and environmental parameters were found in model-fitting analyses.  相似文献   
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