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881.
A previous study (Tr?ster, 1989) showed that nonhandicapped persons preferred a physically handicapped interaction partner to a nonhandicapped partner in an attributionally unambiguous situation. In order to test whether this "sympathy effect of physical handicap" is based on tendencies of impression management, 48 female subjects had to choose to sit next to either a physically handicapped or nonhandicapped female interaction partner in order to view a film together. Attributional ambiguity was varied by either confounding the choice of an interaction partner with a second, socially acceptable alternative (attributionally ambiguous situation: a choice between two films) or not confounding it (attributionally unambiguous situation: no choice between films). Public responsibility was manipulated by informing the subjects about their freedom to choose where they wished to sit either in public (public responsibility) or in private (no public responsibility). The results supported the impression management hypothesis: The handicapped interaction partner (in a wheelchair) was only preferred when the subjects had to anticipate that observers would deduce a preference of the chosen partner from the subjects' choices because of the attributionally unambiguous situation and the public announcement of their freedom of choice. Results suggest that the nonhandicapped strive to exhibit positive and nondiscriminative behavior toward the handicapped in order to avoid creating a disadvantageous impression in an observer.  相似文献   
882.
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   
883.
This study was designed to test whether information transmission between the perceptual and motor levels occurs continuously or in discrete steps. Ss performed visual search across nontargets that shared visual features with one of two possible targets, each assigned to a different response. In addition to reaction time, psychophysiological measures were used to assess the duration of target search and the onset of central and peripheral motor activity. Nontargets sharing features with a target selectively activated the response associated with that target, even when it was not present in the display. This suggests that information transmission to the motor level can consist of fine-grained visual information and that visual search and response selection occur in parallel.  相似文献   
884.
885.
The authors propose a diagnostic for distinguishing between serial and parallel processing in visual search; it is based on testing for subadditive effects of a within-trial visual quality manipulation on target-absent trials. It was evaluated in 2 experiments wherein parallel and serial processing might be expected on the basis of previous work and was then applied to a more uncertain situation in a third experiment. The diagnostic indicates parallel processing of stimuli that differ from each other on a featural basis (Xs and Os) and canonical letters that differ in line arrangement (Ts and Ls) but serial processing when Ts and Ls are randomly rotated. These results form a coherent pattern that is understandable in terms of the literature on visual search, and thus they suggest that the diagnostic may be a useful addition to the methodology used to distinguish between serial and parallel processes.  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.
The effects of increasing work (force) requirements on energy expenditure and response topography were examined in 7 rats pressing a beam to earn food. For the 1st 16 days, the force requirement was 5.52 x 10(-2) N (5.625 g). This increased by 4.91 x 10(-2) N (5 g) every 7th session until Ss had experienced 10 upward shifts. Following the 54.57 x 10(-2) N (55.625 g) condition, the original criterion was reinstated. During the augmented phase. Ss maintained stable reinforcement rates across conditions by increasing the peak force of beam pressing. These higher forces, occurring within 20 reinforcements of changing the force criterion, were produced primarily by increases in the rate of change of force (delta F/delta T). Also, while the rate of work performed on the beam increased, the overall energy expenditure fell. In contrast to these rapid adjustments, reinstating the original 5.52 x 10(-2) N (5.625 g) criterion resulted in only gradual alterations in motor performance.  相似文献   
888.
Immediate post-training subcutaneous administration of lysine vasopressin (LVP, 0.003-1.00 microgram/kg) enhanced retention, whereas the vasopressin antagonist AAVP (0.01-0.30 microgram/kg) impaired it, in male Swiss mice tested 48 h after training in an inhibitory avoidance task. Both effects were dose-dependent. Neither LVP nor AAVP affected response latencies in mice not given the footshock on the training trial. The simultaneous administration of AAVP at a dose (0.01 microgram/kg) which had no effect on retention shifted the dose-response curve of LVP to the right. Nicotine (1.0-30.0 micrograms/kg, sc), a central nicotinic cholinergic agonist, also facilitated retention in a dose-related manner without affecting the retention performance of unshocked mice. The effect of nicotine was prevented by the central acting nicotinic cholinergic receptor antagonist mecamylamine (5 mg/kg, sc.). In contrast, neither hexamethonium (5 mg/kg, sc), a peripheral acting nicotinic receptor blocker, nor atropine (0.5 mg/kg, sc) or methylatropine (0.5 mg/kg, sc), two anticholinergic drugs which are known to act on muscarinic cholinergic receptors, prevented the effect of post-training nicotine. The effects of LVP and nicotine were time-dependent, suggesting that both treatments enhanced retention by influencing post-training processes involved in memory storage. Low doses of nicotine (1.50 microgram/kg, sc) or the central anticholinesterase physostigmine (35 micrograms/kg, sc) and LVP (0.003 microgram/kg, sc), which had no effect on retention when administered alone, produced a synergistic interaction when given together following training. The influence of LVP (0.03 microgram/kg, sc) on retention was prevented not only by AAVP (0.01 microgram/kg, sc) but also by mecamylamine (5 mg/kg, sc), whereas the effects of nicotine (10.0 micrograms/kg, sc) were prevented only by mecamylamine. These results suggest that the enhancement of retention induced by vasopressin is probably due to an activation of central nicotinic cholinergic mechanisms which are critical for memory formation.  相似文献   
889.
Symptom schemata in chronic respiratory patients   总被引:1,自引:0,他引:1  
In view of evidence that illness prognoses and adaptive functioning may be influenced by the accuracy of people's knowledge about their physical symptoms, the present study extended these findings to the chronic care population. It was hypothesized that individuals hold beliefs and develop theories about their physical symptoms and that the accuracy of these beliefs is predictive of the individuals' general level of adaptive functioning. A modified version of an instrument designed to measure the accuracy of illness schemata was employed with a sample of 31 chronic respiratory patients. Accuracy rating correlated positively and significantly with ratings of adaptive functioning, whereas no relationship was observed between adaptive functioning and severity of the patients' medical condition. Well-informed patients functioned at a higher level physically, psychologically, and socially than less-informed patients. These findings point to the importance of patient education for prognosis. Possible mediating factors are discussed.  相似文献   
890.
This study examined the effects of personal religious orientation, religious denomination, and gender on attitudes toward women and their work roles using a sample of 263 single undergraduate university students. Subjects with a high intrinsic religious orientation put significantly more emphasis on family than career in their anticipated general lifestyle relative to those with a low intrinsic religious orientation. Subjects with a high intrinsic religious orientation were also more likely to anticipate the female spouse spending less time in a profession during the children's early years. Males showed more traditional attitudes toward women than females, but there were no gender effects on measures of preferred general lifestyle, preferred child-care distribution, or preferred career involvement for the wife. Subjects belonging to mainline and conservative denomination did not differ significantly in their attitudes toward women or their work roles.  相似文献   
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