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741.
The effects of reinforcement schedules on rats' choice behavior in extinction were studied. In a free-operant chamber equipped with two retractable bars, the experimental animals were trained to press the bars separately for a food reward. One bar delivered the reward on a continuous reinforcement (CRF) schedule, and the other delivered the reward on a partial reinforcement (PRF) schedule. Control animals earned the reward from both bars with the same reinforcement schedule, either a CRF or a PRF. When both bars were simultaneously available during extinction, the experimental animals responded more frequently to the CRF than to the PRF alternative, demonstrating a reversed within-subjects partial reinforcement extinction effect (PREE). A conventional between-subjects PREE was replicated in the control subjects. The results of this study were inconsistent with both Amsel's (1962, 1967) frustration hypothesis and Capaldi's (1966, 1967) sequential hypotheses.  相似文献   
742.
Subjects presented with sets of three samples, two of distilled water and one of tap water, were significantly more consistent in choosing the tap water as preferable than they were in identifying it as the odd sample in the set. The result is opposite to the prediction of high-threshold models of sensory discrimination, which say that if a difference is not noticed, preferences will be random, whereas if a difference is noticed, preferences may still be in either direction. The result can be quantitatively explained by a model advanced by Frijters to explain an analogous anomaly found with the triangle test used in the food industry. Applying his model to the observed proportions yields essentially equivalent estimates of sensory difference (d' = 1.5, approximately) from the two tasks, and a direction of preference almost unanimously in favor of the tap water that was used. Since the model predicts that the proportion of subjects choosing the odd item will depart further from chance in the preference task than in the oddity task, the former has greater power to reject the null hypothesis of no sensory difference if one exists and if preference is overwhelmingly in one direction.  相似文献   
743.
Elderly women in subjectively good health--free of acute illness and major sleep pathologies--who were self-identified as good (n = 22) and poor (n = 16) sleepers were compared on measures of physical health, psychological symptoms, psychosocial status, and life-style. Poor sleepers reported longer sleep latencies, less total sleep time, more nonrestorative sleep, and more daytime fatigue than did good sleepers. Sleep recordings confirmed subjective reports, with shorter total sleep times and trends for lower sleep efficiency, longer sleep latencies, and more wake-after-sleep onset among women with subjective poor sleep. Poor sleepers also were more frequent users of sedative-hypnotic medications in the past. Current medication use, alcohol and caffeine use, daytime napping, and exercise were equivalent in both groups. Psychosocial status failed to discriminate groups. Poor sleepers reported significantly more psychological symptoms than did good sleepers. The levels of both psychological symptoms and sleep disturbance were mild.  相似文献   
744.
We evaluated the efficacy of the Addiction Potential Scale (APS) and the Addiction Acknowledgement Scale (AAS), two new scales designed to assess substance abuse problems with the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), in samples from settings different from those used in their development. Results replicate earlier findings that both scales discriminate between psychiatric and substance abuse samples and do so more effectively than other substance abuse scales designed for use with the MMPI and carried over to the MMPI-2. Results also suggest that APS may be more resistant than AAS to response distortion.  相似文献   
745.
This report examines the changing role of social supports in the bereavement of spouses of elderly suicide and natural deaths, focusing on differences and similarities in relation to gender, time, and mode of death. Measurements were obtained 4 times after death (within 2 months, at 6 months, at 12 months, and at 2 to 2 1/2 years) on 79% of the 108 survivors of elderly suicide, 89% of the 199 natural death survivors, and 79% of the nonbereaved controls. The results indicated that the suicide survivors received significantly less emotional support for their feelings of depression and grief than the natural death survivors, and that they did not confide in the persons in their network any more than the nonbereaved controls did. Women report receiving more support overall than men. A low spot in social supports occurred at the 6-month point after loss for both bereaved groups, but primarily in practical help received by natural death survivors. By the end of the second year, both practical and emotional supports had increased to at least the same level as immediately after death.  相似文献   
746.
The transparency argument concludes that we're directly aware of external properties and not directly aware of the properties of experience. Focusing on the presentation used by Michael Tye (2002) I contend that the argument requires experience to have content that it cannot plausibly have. I attribute the failure to a faulty account of the transparency phenomenon and conclude by suggesting an alternative understanding that is independently plausible, is not an error‐theory and yet renders the transparency of experience compatible with mental‐paint style views.  相似文献   
747.
Very little research has focused exclusively on the workplace experiences of transsexual employees. Studies that have been done are either qualitative case studies (e.g., Budge, Tebbe, & Howard; 2010; Schilt & Connell, 2007), or aggregate transsexual individuals with lesbian, gay, and bisexual employees (e.g., Irwin, 2002). The current study focuses on this underexamined population and examines general workplace experiences, and both individual and organizational characteristics that influence transsexual employees' job attitudes. Results reveal that organizational supportiveness, transsexual identity centrality, and the degree to which they disclose to individuals outside of work all predict transsexual employees' disclosure behaviors in the workplace. These disclosure behaviors are positively related to job satisfaction and organizational commitment, and negatively related to job anxiety. These relations are mediated by coworker reactions. This research expands knowledge about diverse employee populations and offers both theory and some of the first large-scale empirical data collected on the workplace experiences of transsexual employees.  相似文献   
748.
Employing the motivational basis of the false consensus bias, this study hypothesized that the degree of assumed similarity to in-group attitudes would differ among supporters of various political groups in intergroup conflict. We defined a conflict-maintaining bias, the adversary's extremity bias, and examined how the degree of the bias would also differ among supporters of various political groups. Data were gathered from Arab and Jewish high school and university students in Israel. Our hypotheses, that in intergroup conflict assumed similarity to in-group attitudes and the adversary's extremity bias would be greater among supporters of less conciliatory political parties than among supporters of more conciliatory political parties, were supported for one group in the conflict but not the other. Explanations of our findings are based on the differential power status of the 2 groups in the particular conflict.  相似文献   
749.
The auditory cortex of the mustached bat shows complex multiple frequency maps, because cortical neurons in several areas are tuned to particular combinations of signal elements. Different types of combination-sensitive neurons form computational maps in which information-bearing parameters for echolocation (biosonar) are represented systematically. Neuronal response properties and multiple-frequency and computational maps were considered to be created solely by divergent-convergent interactions of neurons in the 'ascending' system. However, we have found that the 'corticofugal' system also plays an important role. Neurons in an iso-best frequency (or echo delay) 'minicolumn' of the auditory cortex augment the auditory responses of subcortical neurons tuned to that frequency (or echo delay) and sharpen their tuning. At the same time, they reduce the response and shift the tuning of subcortical neurons tuned to other frequencies (or echo delays) away from the best frequency (or delay) of the cortical neurons. Cortical neurons mediate a highly focused positive feedback, incorporated with widespread lateral inhibition, via corticofugal projections. This 'egocentric selection' is expected to play an important role in self-organizing the central auditory system.  相似文献   
750.
Older (n = 12) and younger (n = 12) golfers attempted to hit a golf ball into a target net a short distance away. An accelerometer attached to the back of the clubhead measured the applied force. In contrast to the more typical finding of slower perceptual-motor performance by older adults, older golfers reached their peak downswing force earlier in the shot and also exhibited a trend toward a faster overall speed or tempo of the shot. Additionally, older golfers exhibited greater changes in applied force and greater variability. A pattern of divergence among the force-time histories from multiple shots suggested that the overall person-plus-golf-club dynamics were unstable during a part of the shot. Older adults may be slower in controlling this instability. Half of the participants heard a tone whose pitch was proportional to their force. These participants had a slower follow through; however, they did not make significantly more or fewer shots than participants who had not been presented with the tone. Analyses of the temporal covariation among the backswing, downswing, and follow-through favored a chain-like temporal structure over a hierarchical, proportional structure. The pattern of covariation suggests that the tempo and rhythm of the shot are not independent and that changing one's tempo may disrupt rhythm.  相似文献   
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