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881.
In adult listeners, the signal-to-noise ratio at masked threshold remains constant with increases in masker level over a wide range of stimulus conditions. This relationship was examined in 7-month-old infants by obtaining masked thresholds for .5- and 4-kHz tones presented in four levels of continuous masking noise. Adults were also tested for comparison. Masker spectrum levels ranged from 5 to 35 dB/Hz for .5-kHz tones, and from -5 to 25 dB/Hz for 4-kHz stimuli. Thresholds were determined for stimuli of both 10 and 100 msec in duration. The results indicated that infants' performance was more adult-like for 4-kHz stimuli. Although mean thresholds for both 10- and 100-msec, 4-kHz tones were approximately 7 dB higher in infants than in adults, E/N0 at threshold remained essentially constant over the 30-dB range of maskers employed. By contrast, infants' thresholds for .5-kHz tones were exceptionally high at lower levels of the masker. Threshold E/N0 decreased significantly as masker level increased from 5 to 35 dB/Hz, and this decrease was significantly greater for 10- than for 100-msec stimuli. Temporal summation of .5-kHz tones, measured as the difference between thresholds obtained at the two signal durations, was greater for infants than for adults at low levels of the masker. However, because infants' thresholds improved more rapidly with level for 10- than for 100-msec tones, age differences in temporal summation were no longer significant when masker spectrum level was 35 dB/Hz. These results suggest that the relationship between signal-to-noise ratio at masked threshold and level of the masker is dependent on both signal frequency and duration during infancy.  相似文献   
882.
Past research has verified that observers assume that objects are reliably oriented with respect to a gravitationally centered coordinate system. Observers also appear to attend more to specific parts of objects, like faces, that typically are closer to the top. In the present work, we explored whether or not observers have a generic bias to view tops as being more salient than bottoms. In three experiments, observers indicated whether random shapes appeared to be more similar to comparison shapes that shared identical tops rather than bottoms. Observers exhibited a reliable tendency to match figures with similarly shaped tops. Matching choice was also a function of global shape attributes such as axis of elongation or size. The findings are consistent with the notion that, in nature, tops tend to be the most visible part and to provide the best information with respect to important aspects of objects such as animal intentionality and artifact functionality.  相似文献   
883.
This study used an event-based approach to provide empirical evidence regarding the nature of coordination in 3- and 6-month-old infants. Vocalizations and facial actions of 12 normally developing infants interacting with their caregivers were coded. Coded vocalizations and facial actions were considered coordinated when they temporally overlapped. Results indicate that infants coordinated their vocalizations and facial actions more than expected by chance. Coordinated events were governed by 2 sequence patterns. When 2 communicative events were temporally associated across modalities, 1 event tended to be completely embedded within the other, and vocalizations tended to end before facial actions. This study provides new information about how infant communication is structured, confirms results from other coordination studies, and describes a new method for analysis of event-based data.  相似文献   
884.
On tasks that require overcoming an obstacle along an existing path to a physically present goal, infants and very young children evince planning. In each of 3 experiments, the authors tested 21- and 27-month-olds' ability to construct a path to a mentally re-presented goal. Across experiments, the authors varied the number and type of cues to the solution provided. After exposure to the goal-state configuration of problems, both age groups showed evidence of planning (Experiment 1). Demonstration of the initial step in the solution path in Experiment 2 was not as effective as exposure to the goal state in Experiment 1. Even with specification of a greater proportion of the goal path, goal-state configuration information was particularly effective in facilitating performance (Experiment 3). The results suggest productive generation of solutions to novel problems by young children; planning is facilitated by goal-state configuration information.  相似文献   
885.
The relations between temperament and empathy in 2-year-olds.   总被引:2,自引:0,他引:2  
The role of infant and toddler temperament in the prediction of empathy in 2-year-old children was examined. Assessments of temperament included reactivity and affect observed at 4 months of age, as well as inhibition at Age 2. Empathy was measured in 2-year-old children's responses to simulations of distress performed by their mothers and by an unfamiliar person. Children showed relatively more concern for the mother's distress, but they were also responsive to unfamiliar victims. Infants who were unreactive and showed little affect also showed less empathy toward the unfamiliar adult almost 2 years later. Inhibition toward an unfamiliar adult (but not toward the mother) at 2 years of age was negatively related to empathy. Inhibited temperament may thus have a major impact on young children's empathy in unfamiliar contexts. Findings also highlight the need to consider early underarousal as another dimension of temperament that may dampen expressions of empathic concern.  相似文献   
886.
Using a combination of classical test theory and Rasch item analysis, we developed a short scale designed to measure the effectiveness of mental health treatment across a wide range of mental health services and populations. Item development for the scale was guided by literature review and interviews with senior clinicians and with patients. Using 3 different samples consisting of inpatients, outpatients, and nonpatients, we reduced our initial item pool from 81 to 10 items. The 10-item scale had an alpha of .96 and showed strong correlations with commonly used measures of psychological well-being and distress. Our results suggest that the scale appears to measure a broad domain of psychological health. The scale appeared to lack ceiling and floor effects, and it discriminated between inpatients, outpatients, and nonpatients, suggesting the scale has excellent potential to be broadly responsive to a variety of treatment effects. In addition, the new scale proved to be sensitive to treatment changes in a sample of 20 psychiatric inpatients. Overall, the initial data suggest that we have developed a brief, sensitive outcome measure designed to have wide application across psychiatric and psychological treatments and populations.  相似文献   
887.
This study of 927 employees in Taiwan is an attempt to explain job satisfaction and sex differences with reference to work values. Initially, the results confirmed that both job satisfaction and work values consisted of 4 common dimensions pertaining to the task, team, reward, and status. Subsequent analyses showed that male employees had higher rank and higher task, team, and status satisfaction than did female employees. The sex difference was not attributable to differences in work values. Placing higher values on the task and team dimensions and a lower value on the reward dimension seemed to lead to greater job satisfaction.  相似文献   
888.
This study investigated minor psychiatric morbidity ("neurotic": anxiety and depression symptoms) in rural (Black) South African secondary school pupils. The sample included 622 Grade 11 pupils (254 boys and 368 girls) in the age range of 17 to 24 years with a mean age of 19.3 yr. The inventories used were a questionnaire on the socioeconomic and family background, a Cultural Orientation Scale, a Student Stress Scale, a General Self-efficacy Scale, a Perceived Stress Scale, and the Self-reporting Questionnaire-20. The findings are that 12.6% of the pupils had a possible clinically significant psychological disorder. Contributing factors identified were interpersonal, study, finance, illness, perceived stress, low self-efficacy, and low religious orientation.  相似文献   
889.
Age-eligible women enrolled in the National Breast and Cervical Cancer Early Detection Program can obtain free or low-cost mammograms annually, but many do not routinely complete rescreening. This study investigated the rescreening behavior of low-income women by conducting 8 focus groups in Texas with enrollees who had access to free mammograms. Concerns mentioned in the focus groups included fear of radiation, anxiety that the test might not find a cancer that was there, and worries that cancer might be detected. In all groups, some women mentioned the embarrassment, discomfort, or pain they experienced during a prior mammogram, although no one indicated they would refuse to have another mammogram because of these concerns. Findings highlight the useful insights that can be obtained from focus groups and underscore the need for more research on aspects of the experience of mammography that may affect rescreening.  相似文献   
890.
Three experiments were conducted to examine whether timing processes can be shared by continuous tapping and drawing tasks. In all 3 experiments, temporal precision in tapping was not related to temporal precision in continuous drawing. There were modest correlations among the tapping tasks, and there were significant correlations among the drawing tasks. In Experiment 3, the function relating timing variance to the square of the observed movement duration for tapping was different from that for drawing. The conclusions drawn were that timing is not an ability to be shared by a variety of tasks but instead that the temporal qualities of skilled movement are the result of the specific processes necessary to produce a trajectory. These results are consistent with the idea that timing is an emergent property of movement.  相似文献   
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