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791.
Selective attention to multidimensional auditory stimuli   总被引:3,自引:0,他引:3  
Event-related brain potentials (ERPs) elicited by multidimensional auditory stimuli were recorded from the scalp in a selective-attention task. Subjects listened to tone pips varying orthogonally between two levels each of pitch, location, and duration and responded to longer duration target stimuli having specific values of pitch and location. The discriminability of the pitch and location attributes was varied between groups. By examining the ERPs to tones that shared pitch and/or locational cues with the designated target, we inferred interrelationships among the processing of these attributes. In all groups, stimuli that failed to match the target tone in an easily discriminable cue elicited only transitory ERP signs of selective processing. Tones sharing the "easy" but not the "hard" cue with the target elicited ERPs that indicated more extensive processing, but not as extensive as stimuli sharing both cues. In addition, reaction times and ERP latencies to the designated targets were not influenced by variations in the discriminability of pitch and location. This pattern of results is consistent with parallel, self-terminating models and holistic models of processing and contradicts models specifying either serial or exhaustive parallel processing of these dimensions. Both the parallel, self-terminating models and the holistic models provide a generalized mechanism for hierarchical stimulus selections that achieve an economy of processing, an underlying goal of classic, multiple-stage theories of selective attention.  相似文献   
792.
It was hypothesized that one mechanism of self-control that children develop is the strategic capacity to select the experiences they encounter. This hypothesis led to the prediction that children would deal with certain aversive social experiences by seeking out or taking advantage of opportunities for nurturant experiences. Young children were exposed to an aversive social experience in which they received less nurturance than a peer, a positive experience in which they received more nurturance, or a neutral experience in which nurturance was equal. Subsequently, an opportunity was provided for children to control the length of time they watched a highly nurturant television program. As predicted, boys experiencing an aversive social encounter increased the length of time they exposed themselves to the nurturant television show, and their level of reduced positive affect was related to how long they watched the nurturant content, further supporting the interpretation that they did so in response to their own affective state. Girls did not adopt the strategy of self-exposure to nurturant television but did appear to engage in self-distraction during the aversive social experience. Despite the apparent use of control strategies, there was no indication that these strategies were effective for the amelioration of reduced positive affect resulting from the aversive social experience. Discussion focuses on the sex differences observed in the adoption of strategic behavior and factors contributing to the ineffectiveness of the control strategies. A general model is proposed for personal and environmental factors requisite for the selection, employment, and effectiveness of strategies to control experiences and their affective consequences.  相似文献   
793.
The efficiency of an aerobic conditioning program (jogging) is compared to cognitive therapy (stress inoculation) and a waiting list control in modifying self-reported chronic stress. The participants were community residents; 48 were females and 25 were males. Treatment sessions were conducted over a 10-week period with subjects meeting in small groups for 112 hours per week. The State/Trait Inventories, a Tension Thermometer and a submaximal bicycle ergometer test were administered pre, post and follow-up. Repeated measures, multivariate analysis of variance indicated that both treatments were effective in reducing stress compared to the waiting list control and that these changes were maintained at 3-month follow-up. Multivariate analysis indicated that participants with higher initial levels of aerobic fitness did not report less stress, while participants who obtained higher levels of fitness during the conditioning program fared no better in reducing stress than their counterparts who obtained lower levels of aerobic fitness. These findings are of interest because they suggest that the psychosocial components of the fitness program were active ingredients of treatment rathee than the effects of improved cardiovascular functioning.  相似文献   
794.
Rural mental health in America   总被引:3,自引:0,他引:3  
Mental health services are in short supply in rural America. This article describes both the mental health service needs in rural areas and the barriers to improving the availability, accessibility, and acceptability of rural mental health services. Federal programs in rural mental health care in the Departments of Health and Human Services, Agriculture, and Education are described, as well as selected congressional initiatives. The role of the federal Office of Rural Health Policy is emphasized, and policy recommendations for improving rural mental health care delivery are presented.  相似文献   
795.
This study compares social relationships of 677 mothers in families requesting shelter with those of 495 mothers in housed families, randomly selected from the public assistance caseload in New York City. As hypothesized, women seeking shelter had experienced higher levels of a variety of childhood and adult events indicative of disruptions in social relationships. Contrary to our hypothesis, they were more likely than were housed mothers to have had recent contact with parents, other relatives, and friends, although they felt less able to draw on these resources for help with their current housing needs. More than three fourths of families seeking shelter had already stayed with members of their social network in the past year. The data suggest that they had used up potential sources of support before turning to public shelter.  相似文献   
796.
Homelessness and dual diagnosis.   总被引:8,自引:0,他引:8  
People who are dually diagnosed with severe mental illness and substance use disorders constitute 10%-20% of homeless persons. They are a heterogeneous and extremely vulnerable subgroup with complex, poorly understood needs. In this article recent research on the epidemiology, subject characteristics, and service needs of the dually diagnosed homeless population is reviewed. Also, the range of evolving approaches to providing social services, housing, and mental health and substance-abuse treatments; the relevant system issues and legal issues; and problems with current research, as well as future research directions, are discussed. The importance of the distinction between providing appropriate living environments and mental health treatments emerges throughout.  相似文献   
797.
798.
799.
On the semantic content of subcategorization frames   总被引:3,自引:1,他引:2  
This paper investigates relations between the meanings of verbs and the syntactic structures in which they appear. This investigation is motivated by the enigmas as to how children discover verb meanings. Well-known problems with unconstrained induction of word meanings from observation of world circumstances suggest that additional constraints or sources of information are required. If there exist strong and reliable parallels between the structural and semantic properties of verbs, then an additional source of information about verb meanings is reliably present in each verb's linguistic context. Five experiments are presented which investigate the following hypothesis regarding the scope of these relations: The closer any two verbs in their semantic structure, the greater the overlap should be in their licensed syntactic structures. To investigate this hypothesis, data of two kinds were collected from different groups of subjects: (a) One group of subjects was asked to judge the semantic relatedness of verbs by selecting the semantic outlier in triads presented to them. (b) A second group of subjects was asked to judge the grammaticality of these same verbs in a large range of syntactic environments. These two types of data were then compared to assess the degree of correspondence in the two partitionings (syntactic and semantic) of the verb set. The findings, overall, support the view that the syntax of verbs is a quite regular, although complex, projection from their semantics. In conclusion, we discuss the kinds of features that are formally marked in syntactic structure and relate these to the problem of verb-vocabulary acquisition in young children.  相似文献   
800.
Handedness among architects was determined by mail survey. Contrary to previous reports, no evidence was found of an excess of left-handers among a sample of 236 fully qualified male architects and 78 male architectural students. A second study examined whether the use of mail surveys systematically biases the returns of handedness questionnaires. For this, questionnaires were sent to 1,017 university students. No evidence was found for a bias amongst those who did and did not reply to the initial questionnaire. These results strengthen the findings of the first study.  相似文献   
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