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841.
To determine the frequency and correlates of nonsuicidal physically self-damaging acts in 12–14 year olds, a two stage epidemiologic survey with a self-administered questionnaire (N=3283) followed by a psychiatric interview of a subsample of the adolescents and their parents (N=444) was used. Prevalence estimates of interview validated nonsuicidal physically self-damaging acts were 2.46% in males and 2.79% in females. Significant relationships were found between nonsuicidal physically self-damaging acts and suicidal ideation, major depression and undesirable life events. Data suggest that physically self-damaging acts occur at substantial rates during early adolescence. The strong correlation between nonsuicidal self-destructive acts and both suicidal ideation and major depression clarifies prior conflicting reports in the literature and suggests that a history of self-damaging acts should be taken into consideration when evaluating for possible depression and suicide risk.  相似文献   
842.
843.
Direct-observation procedures were used to objectively and efficiently assess several classes of service provided for individuals residing at two state facilities for the developmentally disabled. Time samples were taken of the condition of the clients' physical environment and of the clients themselves. The ongoing behavior of both clients and staff also was recorded. Each residence was observed at least three times during both regular work hours and evening/weekend hours. Results showed that both facilities scored high in the categories regarding the physical condition of the living areas, as well as the categories concerning the condition of the clients. Greater variability was seen in the data on client and staff behavior. More generally, the results indicate that time-sampling procedures can be used efficiently to collect data on multiple aspects of service delivery for large numbers of individuals.  相似文献   
844.
Five questions concerning the properties of spatial representations are explored. (1) How accurately does a spatial representation correspond to the true scene? (2) If inaccurate, how does it differ? (3) Are representations of a familiar scene more accurate than those of an unfamiliar one? (4) Do representations of a scene currently in view differ from those retained in memory? (5) Do the representations of the blind have properties comparable to those-of the sighted? Seven sighted and 7 highly mobile blind subjects, all familiar with a room, and 6 sighted subjects unfamiliar with it, were asked to estimate the absolute distances between 10 salient objects in the room. The 14 familiar subjects made their estimates twice: while they were in the room, and while they were remote from it. Regression analyses showed that the estimates of all subjects had strong metric properties, being linearly related to true distance, with a true zero point; and multidimensional scaling showed that all subjects produced distance estimates that could be scaled in two dimensions to closely match the actual locations of the objects. Familiarity had no effect. The effect of location of testing was the same for both the sighted and the blind: all subjects displayed better spatial knowledge when tested in the room; and all subjects underestimated true distance substantially when tested out of the room. The results showed no qualitative differences as a function of blindness, at least for these highly skilled blind travelers.  相似文献   
845.
A formal approach to the phenomenon of perceptual grouping by proximity was investigated. Grouping judgments of random dot patterns were made by the CODE algorithm (van Oeffelen & Vos, 1982) and several related algorithms, and these judgments were compared with subjects’ grouping judgments for the same stimuli. Each algorithm predicted significantly more subject judgments than would be expected by chance. The more subjects agreed on how a given dot pattern should be grouped, the more successful was the algorithms’ ability to match the judgments for that pattern. CODE predicted significantly fewer subject judgments than did some of the other algorithms, largely because of its overemphasis on the extent of interactivity among dots as they are being grouped.  相似文献   
846.
In the McGurk effect, visual information specifying a speaker’s articulatory movements can influence auditory judgments of speech. In the present study, we attempted to find an analogue of the McGurk effect by using nonspeech stimuli—the discrepant audiovisual tokens of plucks and bows on a cello. The results of an initial experiment revealed that subjects’ auditory judgments were influenced significantly by the visual pluck and bow stimuli. However, a second experiment in which speech syllables were used demonstrated that the visual influence on consonants was significantly greater than the visual influence observed for pluck-bow stimuli. This result could be interpreted to suggest that the nonspeech visual influence was not a true McGurk effect. In a third experiment, visual stimuli consisting of the wordspluck andbow were found to have no influence over auditory pluck and bow judgments. This result could suggest that the nonspeech effects found in Experiment 1 were based on the audio and visual information’s having an ostensive lawful relation to the specified event. These results are discussed in terms of motor-theory, ecological, and FLMP approaches to speech perception.  相似文献   
847.
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   
848.
Two visual half-field experiments tested Moscovitch’s (1979) proposition that cerebral asymmetry does not concern the earliest perceptual stages but only later processing. Subjects were briefly shown displays that included one (Experiment 1) or two (Experiment 2) types of forms differing in size and which, according to previous evidence, might lead to opposite laterality effects. Laterality effects were assessed for correct detections and for illusory conjunctions, both in terms of raw detection scores and in terms of perceptual discriminability (dr scores). In Experiment 1, displays included either rectangles or triangles. In the first case, the target was a cross; in the second case, it was a Star of David. A hemifield x size interaction was observed both on correct detections and on associated discriminability. Yet, no such interaction was obtained for illusory conjunctions or for associated d’ scores. In Experiment 2, the two types of forms were presented simultaneously, with the small ones either inside or outside the large ones. No laterality effects were observed. Some implications of these data for both hemispheric asymmetry and feature integration issues are discussed. The results suggest that early preattentive processes of feature extraction are not lateralized, whereas some integrative mechanisms, such as Treisman’s (1988) focal attention, may operate differently in the two hemispheres.  相似文献   
849.
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   
850.
The relationship between major mental illness and the family is complex. This article describes a model that recognizes biological, individual, and familial aspects of illness, and the interaction and reciprocal effects of these different levels. This model is illustrated using the example of bipolar illness, with particular emphasis on the effects of the illness on the family. Many characteristics previously noted in bipolar families can be understood as consequences, rather than causes, of the illness. A framework for integrated treatment is also described.  相似文献   
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