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31.
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   
32.
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   
33.
A functional analysis of the self-injurious behavior (SIB) of 3 adults with profound developmental disabilities showed that each engaged in SIB in more than one assessment condition. Such outcomes may result from a failure to isolate the variable maintaining SIB, or they may reflect multiple sources of control over SIB. In order to identify more clearly the determinants of SIB, each subject was exposed to a series of treatments appropriate to one or both of the apparent functions of SIB. These treatments, applied sequentially on baselines appropriate to each behavioral function, identified the maintaining variables for SIB through differential outcomes across baselines. Results indicated that the SIB of 2 subjects was multiply controlled, confirming the outcomes of the functional analysis. However, the SIB of the 3rd subject was eliminated using a treatment designed for a single function, suggesting spurious results of the original assessment. Alternative interpretations of undifferentiated assessment data are discussed, as are analysis and treatment issues related to multiply determined behavior disorders.  相似文献   
34.
Summary In this study the role of perceptual and motor factors on the motor organization (integrated versus parallel) adopted by musically skilled and unskilled subjects in a polyrhythmic tapping task was investigated. Subjects tapped a 3:2 polyrhythm to match the timing of two isochronous tone trains, one tone train for each hand. Perceptual factors were examined by the manipulation of the frequency difference between the tone trains to produce either an integrated or a streamed percept. Motor factors were examined by comparison of performance on two versions of the 3:2 polyrhythm. In one (simultaneous) version, each cycle of the polyrhythm began with a simultaneous left- and right-hand tap. In the other (shifted) version a 100-ms interval was introduced between the initial left and right taps in each cycle. Examination of the pattern of variances and covariances among intertap intervals suggested that most of the subjects in this study adopted an integrated motor organization that involved interleaving the timing of the two hands. Further analysis revealed that a serial chained model described the pattern of covariances best for the simultaneous pattern, whereas a hierarchical organization described the pattern of covariances for the shifted pattern best. The finding that performance was more accurate with integrated tones than with streamed tones provides some support for a perceptual-motor facilitation hypothesis.  相似文献   
35.
Previous research on popular images of women and of minority groups has looked almost solely at images of minority men and of white women. This article presents survey data on images of black women among 256 white non-Hispanic college undergraduates, using a modified Katz/Braly scale. The article explores the nature, distribution, correlates, and emotional evaluations of these images and the implications of these images for black women's lives. Images of black women differed substantially from those of American women in general. Most commonly, black women were characterized as loud, talkative, aggressive, intelligent, straightforward, and argumentative. In addition, students rated positive traits less positive and negative traits less negative when exhibited by black women than by American women in general, apparently because of their expectations for black women's behavior.This paper has benefited from the comments of Verna Keith, Wade Smith, and, most especially, Mary Benin. This research was partially supported by Arizona State University Women's Studies Summer Research Awards Program.  相似文献   
36.
Conducted a study of behavior change associated with a street-based AIDS education project targeted to intravenous (IV) drug users in San Francisco. Two cross-sections were sampled from drug detoxification clinics and street locations in 1986 (n = 438) and 1987 (n = 623). Significant increases were reported in the percentage of IV drug users who used bleach to decontaminate syringes, who did not share needles in past year, and in condom use. A significant reduction in an index of the number of needle-sharing partners was reported. Respondents ranked treatment program as most important source of AIDS information prior to implementation of the program, and ranked outreach workers as most important after implementation. Findings suggest that this community-based outreach program had at least some impact on knowledge about AIDS and may have led to reductions in behaviors known to transmit HIV.  相似文献   
37.
Cholinergic-dopaminergic interactions in cognitive performance   总被引:1,自引:0,他引:1  
Both acetylcholinergic (ACh) and dopaminergic (DA) systems have been found to be crucial for the maintenance of accurate cognitive performance. In a series of studies examining those aspects of cognitive function revealed by the radial-arm maze, we have found that these two neurotransmitter systems interact in a complex fashion. Choice accuracy deficits in the radial-arm maze can be induced by blockade of either muscarinic- or nicotinic-ACh receptors. The choice accuracy deficit induced by blockade of muscarinic receptors with scopolamine can be reversed by the DA receptor blocker, haloperidol. The specific DA D1 blocker SCH 23390 also has this effect, whereas the specific D2 blocker raclopride does not, implying that it is D1 blockade that is critical for reversing the scopolamine effect. On the other hand, the choice accuracy deficit induced by nicotinic blockade with mecamylamine is potentiated by haloperidol. This effect is also seen with the D2 antagonist raclopride, but not with the D1 antagonist SCH 23390, implying that it is the D2 receptor which is important for the potentiation of the mecamylamine effect. The relevance of the D2 receptor for nicotinic actions on cognitive function is emphasized by the finding that the selective D2 agonist LY 171555 reverses the choice accuracy deficit caused by mecamylamine. Nicotinic and muscarinic blockade are synergistic in the deficit they produce. Antagonist doses subthreshold when given alone produce a pronounced impairment when given together. This latter deficit can be reversed by the D2 agonist LY 171555. These studies have outlined the complex nature of ACh-DA interactions with regard to cognitive function. Possible neural circuits for these interactions are discussed. The effectiveness of these selective DA treatments in reversing cognitive deficits due to ACh underactivation suggests a novel approach to treating cognitive dysfunction in syndromes such as Alzheimer's disease.  相似文献   
38.
The empirically-based model of malingering and deception described by Rogers (1984b) was operationalized using MMPI and clinical interview data. Subjects (N = 159) were patients committed to an inpatient forensic hospital as ‘Incompetent to Stand Trial’ or ‘Not Guilty by Reason of Insanity’. Inter-rater reliability was acceptable for the 11 criteria used to define response styles. Each subject was categorized into one of five response style groups: ‘Reliable’, ‘Malingering’, ‘Defensive’, ‘Irrelevant’, or ‘Unclassifiable’. Factor analysis of the rating criteria yielded four factors, three of which are comparable to the assigned groups, providing some validation for the constructs underlying these groups.  相似文献   
39.
A widespread view in cognition is that once acquired through extensive practice, mental skills such as reading are automatic. Lexical and semantic analyses of single words are said to be uncontrollable in the sense that they cannot be prevented. Over the past 60 years, apparently convincing support for this assumption has come from hundreds of experiments in which skilled readers have processed an irrelevant word in the Stroop task despite explicit instructions not to, even when so doing would hurt color identification performance. This basic effect was replicated in two experiments, which also showed that a considerable amount of semantic processing is locally controlled by elements of the task. For example, simply coloring a single letter instead of the whole word eliminated the Stroop effect. This outcome flies in the face of any automaticity account in which specified processes cannot be prevented from being set in motion, but it is consistent with the venerable idea that mental set is a powerful determinant of performance.  相似文献   
40.
In the McGurk effect, perceptual identification of auditory speech syllables is influenced by simultaneous presentation of discrepant visible speech syllables. This effect has been found in subjects of different ages and with various native language backgrounds. But no McGurk tests have been conducted with prelinguistic infants. In the present series of experiments, 5-month-old English-exposed infants were tested for the McGurk effect. Infants were first gaze-habituated to an audiovisual /va/. Two different dishabituation stimuli were then presented: audio /ba/-visual /va/ (perceived by adults as /va/), and audio /da/-visual /va/ (perceived by adults as /da/). The infants showed generalization from the audiovisual /va/ to the audio /ba/-visual /va/ stimulus but not to the audio /da/-visual /va/ stimulus. Follow-up experiments revealed that these generalization differences were not due to a general preference for the audio /da/-visual /va/ stimulus or to the auditory similarity of /ba/ to /va/ relative to /da/. These results suggest that the infants were visually influenced in the same way as Englishspeaking adults are visually influenced.  相似文献   
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