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991.
The peak amplitude of EMG activity was measured from the orbicularis oris superior (OOS), orbicularis oris inferior (OOI) and masseter muscles for 3 normal 4-yr.-old children and compared to past data gathered on a group of articulatory disordered children, normal children, and adults. The 4-yr.-olds evidenced greater average peak EMG activity than the other groups, suggesting that speech-sound production becomes more efficient with maturation. Also, levels of variability obtained for the younger children were considerably smaller than for the normal speakers across the three muscles, showing that motor equivalence changes with age whereby the flexibility in the control of articulators increases. The coefficient of variation for the OOI muscle for the disordered children, however, was similar to that for the 4-yr.-olds, while the corresponding data for the other two muscles paralleled those for normal ones. These findings were interpreted as reflecting a delay in the development of speech-motor equivalence that affects certain muscles while sparing others.  相似文献   
992.
40 schizophrenic subjects, divided into paranoid/non-paranoid categories and 14 normal controls were presented a task which involved making "same-different" judgments during random presentations of a series of visual comparison stimuli with a standard which represented the midpoint of the stimulus continuum. Using Sternberg's Choice RT paradigm for studying the locus of cognitive deficit, difficulty at the response-selection stage was manipulated while holding other stages constant. It was predicted that paranoids would have shorter RTs at easy decision points and longer RTs at difficult decision points relative to non-paranoids. The directions of the differences were as predicted but did not attain statistical significance. Both schizophrenic groups, compared to normals, made significantly fewer "same" responses on those trials where the comparison and standard were most similar.  相似文献   
993.
Transient, focal, epileptic-like electrical changes in the temporal lobe, without convulsions, have been hypothesized to be primary correlates of religious experiences. Given these properties, direct measurement of these phenomena within the laboratory should be rare. However, two illustrated instances have been recorded. The first case involved the occurrence of a delta-wave-dominant electrical seizure for about 10 sec. from the temporal lobe only of a Transcendental Meditation teacher during a peak experience within a routine TM episode. The second case involved the occurrence of spikes within the temporal lobe only during protracted intermittent episodes of glossolalia by a member of a pentecostal sect . Neither subject had any psychiatric history. These observations are commensurate with the hypothesis that religious experiences are natural correlates of temporal lobe transients that can be detected by routine EEG measures.  相似文献   
994.
HONESTY TESTING FOR PERSONNEL SELECTION: A REVIEW AND CRITIQUE   总被引:1,自引:0,他引:1  
Paper and pencil predictors of employee theft are described and studies of validity, reliability, and adverse impact of these tests are examined. Validity studies for 10 tests were grouped into 5 categories: comparisons with polygraph examination results, correlations with admissions of past theft, predictive studies using future job behaviors as criteria, comparisons of shrinkage rates before and after the introduction of a testing program, and comparisons of test scores of groups known to be dishonest with groups representing the general population. While positive correlations were consistently found, a variety of methodological differences between studies were identified which make the direct comparison of test validities suspect. High reliabilities are consistently reported, and test score comparisons by race and sex generally report no differences. Ethical issues in honesty test usage are considered and future research needs are identified.  相似文献   
995.
996.
Previous research aimed at quantifying and reducing the decrements encountered in performing manual tasks in cold weather has not described the relationships between task characteristics and cold-induced impairments. The amount of decrement and, often times, the optimal means for reducing the decrement, appear to be task-specific. The research reported here is one in a series of studies formulated to explore those relationships. The strategy is to use tasks from the battery developed by Fleishman (1967) to measure the factorially 'pure' abilities needed to perform all manual tasks. 24 U.S. Marines performed this battery of nine tasks across a range of cold temperatures. To determine if the decrement due to wearing gloves might be less than the decrement due to cold hands as the air temperature decreased, performance on the battery of tasks was measured with and without gloves. Only three of the tasks (abilities) were affected by cold temperatures, and the amount of decrement increased as the air temperature decreased. Three tasks deteriorated due to wearing of gloves, two of those affected by cold and one other. Temperature affected performance independently of the glove effect. Half of the subjects did not complete bare-handed testing at -18 degrees C (approximately 20 min.), indicating this is the lower end of the temperature range in which bare-handed performance for more than a few minutes is practical.  相似文献   
997.
This article reviews three studies giving evidence on the effects of meditation practice on employees' health in the work setting. Although there may be a beneficial role for meditation, unfortunately, these findings await further replication so it would be premature to conclude that meditation practice reduces occupational stress.  相似文献   
998.
Tachistoscopic presentation of light flashes was used to test for differences in visual sensitivity among 3 groups of practitioners of Buddhist mindfulness meditation and non-meditator-controls. Meditation practitioners were able to detect light flashes of shorter duration than the non-meditators. There were no differences among the meditator groups. There were no differences among the groups in ability to discriminate between closely spaced successive light flashes. The lower detection threshold for single light flashes for the meditators may reflect an enduring increase in sensitivity, perhaps the long-term effects of the practice of mindfulness meditation on certain perceptual habit patterns. The lack of significant differences in the discrimination of successive light flashes probably reflects the resistance of other perceptual habit patterns to modification. The results support the statements found in Buddhist texts on meditation concerning the changes in perception encountered during the practice of mindfulness.  相似文献   
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1000.
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