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61.
The recognition of brief vowels was studied in forward and backward masking tasks. In a series of experiments in which both target and mask parameters were systematically varied, two populations of subjects were identified. The majority (Nonmaskers) evidenced little masking at any interstimulus interval, while relatively fewer subjects (Maskers) evidenced backward masking (but not forward masking) over a 100-200 ms interval. Increasing target set size systematically increased masking for the Maskers but not for the Nonmaskers. Adding white noise to the targets increased the extent of masking for both groups. These results suggest (1) that masking does not impose a substantive constraint on vowel perception in running speech, and (2) that multiple strategies may exist for vowel recognition.  相似文献   
62.
Laboratory dogs were trained to press a response panel to postpone shocks during daily one-hour avoidance conditioning periods. Each dog was also confined in the experimental environment for 5 hours prior to the avoidance periods. Blood pressure and heart rate were monitored continuously during these experiments from chronically indwelling arterial catheters. Extended training resulted in the emergence of a cardiovascular response pattern during the pre-avoidance interval characterized by gradual increases in blood pressure together with decreases in heart rate. Elevations in both blood pressure and heart rate were sustained during the avoidance periods. During sessions in which alpha adrenergic activity was suppressed by phenoxybenzamine, absolute levels of blond pressure were found to be lower than during control (non-drug) sessions, but a progressive rise in blood pressure continued to be observed during pre-avoidance. These results suggest that sustained cardiovascular responses during avoidance periods are associated with activation of the sympathetic nervous system, but that the gradual rise in blood pressure during pre-avoidance is due to other factors.  相似文献   
63.
Within the last decade, there has been a sharp global rise in the number of young people identifying as transgender. More recently, there appears to be an increase in the numbers of young people detransitioning or returning to identifying with their natal sex after pursuing medical transition. A case is presented of a young woman who pursued a gender transition and returned to identifying as female after almost two years on testosterone. The author considers and critiques the affirmative model of care for gender dysphoric youth in light of this case.  相似文献   
64.
Neuropsychology Review - The thalamus, a significant part of the diencephalon, is a symmetrical and bilateral central brain structure. The thalamus is subdivided into three major groups of nuclei...  相似文献   
65.
The use of memory wallets to prompt factual information during conversations with day-care center volunteers was evaluated for four subjects with dementia. Memory wallets contained 15–20 pictures and sentences about familiar persons, places, and events that each subject had difficulty remembering. All subjects used the memory wallets to improve their conversations by increasing factual statements and decreasing ambiguous, unintelligible, and perseverative utterances. Volunteers decreased their use of questions and prompts during conversations in which subjects used their memory wallets. These results demonstrate the effectiveness of using volunteers to develop memory wallets and to encourage their use during conversations with day-care clients.  相似文献   
66.
Studies have shown that the multiple-stimulus without replacement (MSWO) preference assessment is an effective assessment format for identifying preferred items. However, it is possible that factors other than reinforcer quality might influence selections by some individuals when the MSWO array consists of edible items. The validity of the MSWO results was evaluated by comparing items identified as most and least preferred by the MSWO assessment in a concurrent-schedule (CS) format. Varying edible items were used in each study. The MSWO format accurately identified the higher quality edible item for most participants across studies (76%); however, the MSWO format did not predict the highest quality edible item in the CS assessment for 20% to 30% of participants in each study.  相似文献   
67.
Science and Engineering Ethics - Scientific peer reviewers play an integral role in the grant selection process, yet very little has been reported on the levels of participation or the motivations...  相似文献   
68.
This longitudinal study examined adolescent girls' perception of control over sexually transmitted disease (STD) acquisition. Participants were asked questions regarding their perception of their STD locus of control (internal control; control by parents, partners, peers, and health care providers; and chance) at two waves of data collection. Of the 116 participants (mean age = 17 years), 82% were African-American and 18% were Caucasian. Responses to the measure of locus of control were significantly correlated across a 6-month interval. The responses regarding internal control, control by partner, and chance were not related to the acquisition of an STD in the next 6 months. Further, they were not influenced by an STD in the preceding 6 months. These results indicate that responses to a locus of control measure were stable over a 6-month period, and internal, partner, and chance locus of control perceptions seem to be neither determined by STD experience nor directly related to future STD acquisition. However, understanding an individual's locus of control may be helpful in providing appropriate counseling. Future research could examine how adolescent girls form their perceptions of control over STD acquisition.  相似文献   
69.
The self-reported violent experiences of adolescents living in a public-subsidized urban high-rise building were examined. This effort was part of an interdisciplinary, community-university collaboration program called the HOME (High-rise On-site Multifamily Environments) Family Support Project. A survey of violent experiences and a one-on-one structured interview were conducted with 20 adolescent residents. Results of the quantitative and qualitative analyses revealed high degrees of exposure to violence among these adolescents, concerns for their personal safety, as well as insights into what they believe adults could and should be doing to address increasing levels of community violence. The implications of these results for conducting ecologically valid research on sensitive issues with adolescents and for family support program planning are discussed.  相似文献   
70.
All languages rely to some extent on word order to signal relational information. Why? We address this question by exploring communicative and cognitive factors that could lead to a reliance on word order. In Study 1, adults were asked to describe scenes to another using their hands and not their mouths. The question was whether this home-made "language" would contain gesture sentences with consistent order. In addition, we asked whether reliance on order would be influenced by three communicative factors (whether the communication partner is permitted to give feedback; whether the information to be communicated is present in the context that recipient and gesturer share; whether the gesturer assumes the role of gesture receiver as well as gesture producer). We found that, not only was consistent ordering of semantic elements robust across the range of communication situations, but the same non-English order appeared in all contexts. Study 2 explored whether this non-English order is found only when a person attempts to share information with another. Adults were asked to reconstruct scenes in a non-communicative context using pictures drawn on transparencies. The adults picked up the pictures for their reconstructions in a consistent order, and that order was the same non-English order found in Study 1. Finding consistent ordering patterns in a non-communicative context suggests that word order is not driven solely by the demands of communicating information to another, but may reflect a more general property of human thought.  相似文献   
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