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91.
Sleep in the dove Zenaida asiatica   总被引:1,自引:0,他引:1  
Electrographic and behavioral observations were made in five adult birds of the genus Zenaida asiatica. Five different vigilance states were quantitated: (1) Active waking (Aw) was characterized by constant behavioral activity; the nuchal electromyogram was tonically active with bursts associated to movements. The electroencephalographic pattern was low voltage and high frequency. (2) Quiet waking (Qw) was characterized by diminished behavioral activity and the EEG pattern was similar to that of Aw. (3) Drowsiness (D) was characterized by behavioral calm. Frequency of cerebral activity diminished progressively, but there were short periods of desynchronization corresponding to brief awakenings. (4) Slow wave sleep (SWS); during this period there was behavioral rest and EEG pattern of continuous slow waves and the nuchal EMG was tonically reduced. Spindles of sleep were not observed. (5) Paradoxical sleep (SP), behaviorally characterized by phasic manifestations consisting of noddings originated by rapid falling down of head and bursts of rapid eye movements. EEG activity was like that of waking state. EMG activity was maintained at the same level as during SWS but sometimes it decreased lightly. Total atonie was not observed. Sleep percentages were higher when recordings were done during the nocturnal period.  相似文献   
92.
Effects of aging and task difficulty on divided attention performance   总被引:2,自引:0,他引:2  
We report two experiments that compare the performance of young and older adults on perceptual-motor tasks involving division of attention. Previous studies have shown older people to be especially penalized by divided attention situations, but the generality of this finding was recently challenged by Somberg and Salthouse (1982). The present study was conducted to investigate the possibility that age differences in dual-task performance are amplified by an increase in the difficulty of the constituent tasks, where difficulty was manipulated by varying the central, cognitive nature of the tasks (Experiment 1) or the degree of choice involved (Experiment 2). With the present tasks, strong evidence was found for an age-related decrement in divided attention performance. Contrary to our original expectations, however, it does not seem that division of attention presents some especial difficulty to older people. Rather, division of attention is one of several equivalent ways to increase overall task complexity. In turn, age differences are exaggerated as tasks are made more complex.  相似文献   
93.
In choice reaction time, stimuli and responses in some combinations (e.g., based on spatial arrangement) are faster than in other combinations. To test whether motion toward a position yields faster responses at that position, a computer-generated square in front of one hand appeared to move either toward that hand or toward the other hand. Compatible responses (e.g., motion toward left hand/left response) were faster than incompatible responses, even when that opposed traditional positional compatibility. In Experiment 2, subjects responded to the same stimuli but with both hands left, right, or on the body midline. Medial responses were the fastest, showing that destination, rather than mere relative position, was a critical variable. It was suggested that spatial compatibility effects are not unique to position but apply to a variety of task situations, describable by J.J. Gibson's theory of affordances, in which he claims that one perceives the actions (e.g., catching) permitted in a situation.  相似文献   
94.
This study evaluated the efficacy of the Garren-Edwards Behavior Modification Program, which uses the Garren-Edwards Gastric Bubble as an adjunct to treatment. Group therapy sessions were conducted with 23 morbidly obese subjects for 6 months on a biweekly basis. Each therapy session used a five-stage problem-solving sequence designed to facilitate adaptive behavioral alternatives. In evaluating weight change, a multivariate analysis of variance was conducted along with two preplanned orthogonal comparisons. Patients lost significant amounts of weight between initial to 3-month (p<.0001) and 3- to 6-month intervals (p<0001). A similar treatment effect was noted in an additional sample of 24 morbidly obese subjects following 3 months of treatment (p<0005). The findings support the value of longer goal-oriented programs in promoting continued weight loss. Implications for treatment process and therapist interventions prompted by this new format are discussed.  相似文献   
95.
96.
The present study was designed to assess whether the conversational behavior of children separated into accepted, rejected, and mixed-status dyads differed along the dimensions of listening to, paying attention to, and indicating interest in their dyadic partner. Conversations of 40 third-grade dyads were analyzed as they occurred in a 2- min waiting period and a 4- min conversation period. Seventeen categories of verbal behaviors that indexed these dimensions were used as content codes. Multivariate analyses of variance performed on the observational data yielded significant main effects for status, sex, and experimental condition. Results are interpreted in terms of previous social skills research, and suggestions for future research are offered.  相似文献   
97.
98.
Differences in reproduction as well as in behavior in the presence of females were evaluated according to dominant and subordinate male rank in albino mice, in the temporary absence of each male's antagonist. Dominant males reproduced more successfully than subordinate males. Subordinate males were generally inactive, except for displacement activities, during the first 15 min they were exposed to female partners. These findings suggest that mechanisms other than male-male interference or mating order may be operating or influencing behavior and reproductive results.  相似文献   
99.
Although stress and anxiety have long been assumed to play an exacerbatory role in asthma, no study has systematically documented that daily exacerbations of asthma symptoms are related to stress and/or anxiety. In this study, 24 airways obstruction patients (12 asthmatics and 12 chronic obstructive pulmonary disease patients) were instructed to monitor the severity of daily respiratory symptoms. In addition, subjects recorded their daily anxiety level and the number and perceived impact of daily stressors. The results showed that although there were differences between high- and low-stress days for both groups, there were no differences between groups on symptom severity or between high- and low-anxiety days, as measured by the State-Trait Anxiety Inventory (STAI). Thus, although the number and impact of daily stressors were found to be directly associated with the severity of asthma symptoms, anxiety does not appear to have a direct role in the exacerbation of asthma. The findings failed to support the anxiety theory of asthma but provided an explanation for the poor results obtained in previous treatment studies which employed anxiety management with asthmatics.  相似文献   
100.
August Dvorak is best known for his development of the Dvorak keyboard. However, Dvorak also adapted and applied many behavioral and scientific management techniques to the field of education. Taken collectively, these techniques are representative of many of the procedures currently used in applied behavior analysis, in general, and especially in precision teaching. The failure to consider Dvorak's instructional methods may explain some of the discrepant findings in studies which compare the efficiency of the Dvorak to the standard keyboard. This article presents a brief background on the development of the standard (QWERTY) and Dvorak keyboards, describes parallels between Dvorak's teaching procedures and those used in precision teaching, reviews some of the comparative research on the Dvorak keyboard, and suggests some implications for further research in applying the principles of behavior analysis.  相似文献   
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