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881.
Fifty-five families of chronically offending delinquents were randomly assigned to parent-training treatment or to service traditionally provided by the juvenile court and community. The families in the parent-training group received an average of 44.8 hours of professional contact (23.3 hours of which were phone contacts), and each control group family received treatment estimated at more than 50 hours on the average. Comparisons of police contact data at baseline and subsequent years for the two groups showed that subjects in both groups demonstrated reduced rates of offending during the followup years. The finding most relevant was significant treatment-by-time effect for offense rates, with most of this effect accounted for by a greater reduction in serious crimes for the experimental group during the treatment year, and a similar reduction of the community control group occurring in the first of three followup years. These early decrements in offense rates persisted during followup for both groups. Throughout the study, boys in the experimental group spent significantly less time in institutional settings than did boys in the control group. Parent training had a significant impact, but the reduction in offending was produced at very high emotional cost to staff. Although it is clear that this population requires substantial treatment resources, this study underscores the need for more work on prevention.Research for this paper was supported by grant MH 37938 from the Center for Studies of Antisocial and Violent Behavior, National Institute of Mental Health (NIMH), U.S. Public Health Service (PHS). The writing was supported in part by grants MH 17126 and MH 37940 from the same Center, grant DA 05304 from the National Institute of Drug Abuse, U.S. PHS., and grant MH 38730 from the Child and Adolescent Disorders Research Branch, NIMH, U.S. PHS. The authors gratefully acknowledge the enduring commitment of the treatment staff that made this study possible: Patricia Chamberlain, Marion Forgatch, and Kate Kavanagh.  相似文献   
882.
Tested a preventive intervention in which peer telephone dyads were developed for low-income, community-living, elderly women with low perceived social support. After an initial assessment, respondents were randomly assigned to either an assessment-only control or received 10 weeks of friendly staff telephone contact. After a second assessment, participants receiving the staff contact were randomly assigned to continue that contact or were paired in dyads to continue phone contact with one another. Dependent variables were measures of perceived social support, morale, depression, and loneliness. All groups, particularly the staff contact group, showed some improvement in mental health scores over time, but there were no significant differences between intervention groups, or between intervention and assessment-only control groups. The results suggest that participation in the study and in personal assessment interviews at home were probably morale enhancing, and that additional telephone contact did not significantly add to that effect. Evidence also indicates that, in this sample, low perceived family support was significantly related to poor mental health, so it is possible that a program designed to increase friend support may have been the wrong intervention.  相似文献   
883.
Task dynamics corresponding to rhythmic movements emerge from interactions among dynamical resources composed of the musculature, the link segments, and the nervous and circulatory systems. This article investigated whether perturbations of interlimb coordination might be effect over circulatory and nervous elements. Stiffness of wrist-pendulums oscillated at a common tempo and at 180 degrees relative phase was perturbed through the use of tonic activity about an ankle. Left and right stiffnesses, the common period, and the phase relation all changed. Stiffnesses increased with ankle torque in proportion to the wrist's inertial load. Despite different changes in stiffness at the two wrists, isochrony was preserved. The stability was shown to be consistent with the proportionality of changes in stiffness to the inertial loads. The phase departed from antiphase in proportion to the asymmetry of inertial loads. The size of departures decreased with increasing ankle torque. An account was developed in terms of muscular, circulatory, and nervous functions.  相似文献   
884.
Trajectory and kinematics of drawing movements are mutually constrained by functional relationships that reduce the degrees of freedom of the hand-arm system. Previous investigations of these relationships are extended here by considering their development in children between 5 and 12 years of age. Performances in a simple motor task--the continuous tracing of elliptic trajectories--demonstrate that both the phenomenon of isochrony (increase of the average movement velocity with the linear extent of the trajectory) and the so-called two-thirds power law (relation between tangential velocity and curvature) are qualitatively present already at the age of 5. The quantitative aspects of these regularities evolve with age, however, and steady-state adult performance is not attained even by the oldest children. The power-law formalism developed in previous reports is generalized to encompass these developmental aspects of the control of movement.  相似文献   
885.
Two experiments report the effects of generating a concurrent position expectancy and form expectancy. Ss were precued to a stimulus position where 1 target shape was most probable, and they made a speeded 2-choice response to the orientation of the displayed shape. Response time (RT) was faster for an expected position than an unexpected position and faster for a likely shape than for an unlikely shape. This replicates the work of Lambert and Hockey (1986). It was also observed, however, that when a stimulus appeared at an unexpected position where 2 shapes were equally improbable, RT was slower for the shape that had been likely rather than unlikely at the cued position. This finding is incompatible with the probability-matching hypothesis of Lambert and Hockey. The data support a hierarchical-expectancy model of attentional selectivity.  相似文献   
886.
Four experiments used the visual search paradigm to examine feature integration mechanisms. Reaction time to determine the presence or absence of a conjunctive target is relatively fast and exhaustive for low-density displays. Search rate is slow and self-terminating for high-density displays. Density effects do not arise when the target is defined by a unique feature. Two mechanisms are proposed for feature integration. A fast mechanism integrates features on the basis of coarse location information coded with the initial registration of the features. This coarse location mechanism requires that display items be spaced apart. A second, slower mechanism is used when objects are clumped together. The 2-mechanism hypothesis provides a resolution to conflicting findings in the visual search and illusory-conjunction literature. A possible interpretation of the findings with a single guided search mechanism for feature integration is also discussed.  相似文献   
887.
Experiments were conducted in which Ss made classification, recognition, and similarity judgments for 34 schematic faces. A multidimensional scaling (MDS) solution for the faces was derived on the basis of the similarity judgments. This MDS solution was then used in conjunction with an exemplar-similarity model to accurately predict Ss' classification and recognition judgments. Evidence was provided that Ss allocated attention to the psychological dimensions differentially for classification and recognition. The distribution of attention came close to the ideal-observer distribution for classification, and some tendencies in that direction were observed for recognition. Evidence was also provided for interactive effects of individual exemplar frequencies and similarities on classification and recognition, in accord with the predictions of the exemplar model. Unexpectedly, however, the frequency effects appeared to be larger for classification than for recognition.  相似文献   
888.
Spontaneously hypertensive (SHR), Wistar-Kyoto (WKY) normotensive, and Sprague-Dawley (SD) normotensive rats were either reared by their natural mothers (controls) or fostered to a mother of one of the other strains. The effects of rearing environment were assessed by measures of body weight at weaning and adult resting mean arterial blood pressure (MAP) and heart rate (HR). At weaning, SHR control rats weighed less than WKY controls which in turn weighed less than SD controls. SHR and WKY rats reared by SD mothers weighed significantly more than their respective controls, whereas SD rats reared by either SHR or WKY mothers weighed less than SD control rats. Manipulation of the maternal environment was attended by a change in adult resting MAP in only one group. SHR rats reared by SD mothers had MAPs which were significantly lower than SHRs reared by their natural mothers. No within-strain adult HR differences were observed between control and cross-fostered groups. These data indicate that the effects of cross-fostering on adult resting MAP previously reported for SHR and WKY animals are generalizable to another normotensive strain. That is, genetically hypertensive (SHR) animals exposed to a normotensive (WKY or SD) maternal environment display a reduction in adult resting MAP, whereas hypertension or an increase in adult MAP is not induced in normotensive rats (WKY or SD) as a consequence of exposure to a hypertensive maternal environment.  相似文献   
889.
The aim of this study was to assess the validity of the notion that anxiety influences maternal style in monkeys. To this end, we investigated the correlations between measures of the quality of mother-infant relationship and scratching, a behavior pattern that reflects a state of anxiety. The subjects were seven group-living macaque mothers and their infants observed during the first 12 weeks postpartum. Postpartum scratching by the mothers was positively correlated with both maternal possessiveness and maternal warmth, two composite measures of the quality of mother-infant relationship that reflect a possessive and attentive maternal style. Evaluation of the correlations between maternal rank and scratching before and after parturition indicated that interactions with their infants, not those with other group companions, were the main source of anxiety for the mothers. These results support the notion that anxiety influences maternal style in monkeys and suggest that studies aimed at investigating physiological and social correlates of maternal emotionality in nonhuman primates could use scratching as a useful and simple behavioral measure.  相似文献   
890.
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