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891.
892.
In both psychiatric and substance-abuse services, clinicians have been concerned with the introduction of automated assessments and with their clients’ reactions toward those assessments. The positive reactions of psychiatric clients have been well documented, but little has been known about substance-abusing clients’ impressions of automated assessments. The impact of automated assessment on clients seeking substance-abuse services was evaluated and compared with a previously analyzed sample of clients seeking mental health services. On the whole, both groups responded similarly and positively to automated assessments. Factor analyses revealed three underlying dimensions in client attitudes toward automated assessment,Completeness and satisfaction,Ease of use and enjoyment, andNegative attitudes. In addition, statistically, though not clinically, significant differences in attitudes were found between various demographic groups. Overall, the results support the use of automated assessments with individuals seeking either substance-abuse or mental-health services. 相似文献
893.
In this paper, we examine whether color and shape, tied to a single object in space, (1) are identified and selected in series or in parallel, (2) are identified and selected in a dependent, self-terminating manner or in an independent and exhaustive manner, and (3) are conjoined by a feature integration process before or only after an initial stage of separate attribute analyses has finished. We measured response time and the selection negativity (SN) derived from event-related brain potentials when participants responded to a unique conjunction of color and shape in a go/no-go target detection task. The discriminability of the color and the shape of the conjunction was manipulated in three conditions. When color and shape were easy to discriminate, the SNs to color and shape started at the same time. When one attribute was less discriminable, the SN to that attribute started later, but not the SN to the complementary attribute. This suggests that color and shape are identified and selected in parallel. In all three discriminability conditions, the SNs to color and shape were initially independent but later interacted. This suggests that color and shape are initially selected independently and exhaustively, after which their conjunction is analyzed. The SN to local shape features started later than that to the conjunction of color and global shape features, which suggests that feature integration can start before the analyses of the separate attributes have finished. 相似文献
894.
Lorraine G. Allan Shepard Siegel Chandani Kulatunga-Moruzi Thomas Eissenberg C. Andrew Chapman 《Attention, perception & psychophysics》1997,59(8):1327-1334
In the typical induction of the orientation-contingent color aftereffect (CCAE), the stimuli are composed of elements that differ in both color and luminance. Three experiments are reported that show that chromatic contrast between stimulus elements is insufficient for the induction of the orientation-CCAE and that luminance contrast is necessary. These experiments expand on previous research concerned with the role of luminance contrast in the induction of orientation-CCAEs by eliminating alternative explanations. 相似文献
895.
James E. Cutting Peter M. Vishton Michelangelo Flückiger Bernard Baumberger John D. Gerndt 《Attention, perception & psychophysics》1997,59(3):426-441
In four experiments, we explored the heading and path information available to observers as we simulated their locomotion through a cluttered environment while they fixated an object off to the side. Previously, we presented a theory about the information available and used in such situations. For such a theory to be valid, one must be sure of eye position, but we had been unable to monitor gaze systematically; in Experiment 1, we monitored eye position and found performance best when observers fixated the designated object at the center of the display. In Experiment 2, when we masked portions of the display, we found that performance generally matched the amount of display visible when scaled to retinal sensitivity. In Experiments 3 and 4, we then explored the metric of information about heading (nominal vs. absolute) available and found good nominal information but increasingly poor and biased absolute information as observers looked farther from the aimpoint. Part of the cause for this appears to be that some observers perceive that they have traversed a curved path even when taking a linear one. In all cases, we compared our results with those in the literature. 相似文献
896.
Ronald Hübner 《Attention, perception & psychophysics》1997,59(2):187-201
There are many conditions in which identification proceeds faster for the global form of a hierarchical pattern than for its local parts. Since the global form usually contains more lower spatial frequencies than do the local forms, it has frequently been suggested that the higher transmission rate of low spatial frequencies is responsible for the global advantage. There are also functional hemispheric differences. While the right hemisphere is better at processing global information, the left hemisphere has an advantage with respect to local information. In accordance with the spatial-frequency hypothesis, it has been speculated that this difference is due to a differential capacity of the hemispheres for processing low and high spatial frequencies. To test whether low spatial frequencies were responsible for the global advantage and/or for the observed hemispheric differences, two experiments were carried out with unfiltered and highpass-filtered compound-letter stimuli presented at the left, right, or center visual field. The first experiment, in which the target level was randomized in each trial block, revealed that low spatial frequencies were not necessary for either global advantage or for hemispheric differences. Highpass filtering merely increased the response times. In the second experiment, the target level was held constant in each block. This generally increased the speed of responding and produced interactions between filtering and global-local processing. It was concluded that both sensory and attentional or control mechanisms were responsible for global precedence and that the hemispheres differed with respect to the latter. 相似文献
897.
Mark A. Barnett Guy D. Vitaglione Kimberly K. G. Harper Steven W. Quackenbush Lee Ann Steadman Birgit S. Valdez 《Journal of applied social psychology》1997,27(15):1316-1334
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames. 相似文献
898.
The present study uses attribution theory to identify factors that may lead to unfavorable emotional reactions toward patients with schizophrenia and to highlight factors that may contribute to the observed inverse relationship between industrial status of a country and schizophrenia outcome. University students from Mexico and the U.S., 2 countries differing in industrial status, served as participants. Eighty-eight Mexicans from Guadalajara and 88 Anglo Americans from Los Angeles, California read vignettes of a patient described to meet DSM-IV criteria for schizophrenia. In one vignette, the patient's disorder was characterized by predominantly positive symptoms (e.g., hallucinations, delusions), whereas in the other vignette negative symptoms (e.g., social withdrawal, apathy) predominated. In support of an attributional approach, negative symptoms were associated with greater perceived control than were positive symptoms. Correspondingly, negative symptoms were found to provoke more intense negative affect and less intense positive affect than were positive symptoms. Some national and gender differences were also found. 相似文献
899.
Curtis W. Hart Robin Scroggs Claude Barbre Antoinette Goodwin Philip Paris Mark J. Hanson Kathryn Madden Annette G.E. Esser Raymond J. Lawrence Jr. Jilisa Snyder Karen A. Monk George M. Klee Loy McGill Jill Carlen Kirby Thandeka Pamela Davis Barnett Gregory Forte J.J. Haines Barry Ulanov Elizabeth MacDonald 《Journal of religion and health》1997,36(1):81-104
900.
11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD-1) catalyses the interconversion of active cortisol and corticosterone with inert cortisone and 11-dehydrocorticosterone, thus regulating glucocorticoid access to intracellular receptors. In rats, chronic glucocorticoid excess or stress increases 11beta-HSD-1 in the hippocampus, producing suggestions that it may attenuate the deleterious effects of chronic glucocorticoid excess. However, 11beta-HSD-1 predominantly catalyses 11beta-reduction in the intact liver and hippocampal cells, thus regenerating active glucocorticoids from inert substrate. We studied 11beta-HSD activity in the tissues of male tree shrews following 28 days of sustained psychosocial stress or exogenous administration of cortisol. In the hippocampus, chronic psychosocial stress attenuated 11-HSD-1 activity (69 +/- 9% of control), whereas cortisol alone had no effect. In the liver, both chronic stress and cortisol administration decreased 11beta-HSD-1 activity (47 +/- 11% and 49 +/- 4% fall, resp.). Attenuation of 11beta-HSD-1 within tissues may reflect a homeostatic mechanism designed to minimise the adverse effects of prolonged stress and/or glucocorticoid excess. 相似文献