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Two experiments are reported which investigated how subject gender and time-of-day influenced the estimation of duration and the perception of task-related mental workload. In the first experiment, 24 subjects performed a filled time-estimation task in a constant blacked-out, noise-reduced environment at 0800h, 1200h, 1600h, and 2000h, respectively. In the second experiment, 12 different subjects performed an unfilled time estimation task in similar conditions at 0900h, 1400h, and 1900h. At the termination of all experimental sessions, participants completed the NASA Task Load Index workload assessment questionnaire as a measure of perceived mental workload. Results indicated that physiological response, reflected in body temperature change, followed an expected pattern of sequential increase with time-of-day. However, estimates of duration and the perception of mental workload showed no significant effects for time-of-day. In each of the experiments there were significant differences in time estimation and mental workload response contingent on the gender of the participant. These results are interpreted in light of the previous positive findings for circadian fluctuation in performance efficiency and the equivocal findings of a gender difference in time estimation. A unifying account of these collective results is given based on gender by time-of-day interactional effects. An earlier version of this paper was presented at the 32nd Annual Meeting of the Human Factors Society, Anaheim, CA, October, 1988.  相似文献   
214.
The authors used a correlated motion paradigm to investigate the effects of aging and gender on motion sensitivity. In 2 experiments with a total of 50 elderly and 50 young subjects, motion thresholds were significantly higher for elderly women. The correlated motion signal, which was embedded in random motion, may have been coherent to subjects in much the same way a form is in Witkin's Embedded Figures Test (EFT). In Experiment 2, EFT scores were obtained. A significant positive relationship between motion thresholds and EFT performance was found within each age group. Although gender-related perceptual style differences may contribute to motion perception effects, the authors argue that a common neural factor contributes to performance on both the EFT and the correlated motion task.  相似文献   
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The relationship between memories of childhood experiences (e.g., adverse parenting) and adult depression often found raises questions of interpretation. On the one hand, both laboratory studies and clinicians' experiences suggest that subjects in a depressed mood frequently show a negative bias in perceptions and memories. Negative childhood memories in depressed persons might, therefore, be interpreted as epiphenomena of depressed mood instead of etiological factors. On the other hand, memories of childhood experiences seem remarkably stable across changes in depressed mood, especially when memories are elicited by means of standardized questionnaires. In the mood and memory literature several explanations for this stability are offered. For one thing, highly structured cues to elicit memories (such as in questionnaires) are hypothesized to be less susceptible to mood bias than unstructured memory cues (such as in free recall procedures). On the other hand, resource allocation theorists suggest that childhood memories, being well established and rehearsed, are relatively impervious to mood bias no matter how they are elicited. In this study we examined whether different methods of eliciting childhood memories (i.e., free recall and questionnaire-cued) are differentially susceptible to mood bias. To this aim, we used a mood induction procedure to induce depressed, neutral, and elated mood and assessed childhood memories both before and after the mood induction using both questionnaires and free recall to elicit memories. Results suggested that memories elicited by means of free recall as well as by means of questionnaire-cued recall were susceptible to depressed and elated mood bias. The implications for research addressing the link between childhood experiences and depression are discussed.  相似文献   
217.
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   
218.
Short-term memory for actions was investigated for young adult and elderly adult subjects with the Brown-Peterson procedure at retention intervals of 0 and 15 s. The short-term memory trials were followed by the long-term recall of the prior to-be-remembered actions. The 15-s retention interval was filled either with no activity or with 1 of 3 different interfering activities. Verbal interference had little effect on short-term memory at either age level. Actions performed in the interval either by the subjects or by the experimenter produced significantly lower recall scores at each age level, with the decrement being more pronounced for the elderly than for the young subjects. The long-term memory results indicated that successful short-term recall enhanced later long-term recall, regardless of age level.  相似文献   
219.
The research questions of this study are the following: To what degree can results such as those of Thayer and colleagues (1978a, 1985, 1986, 1988) concerning diurnal variation and differences between diurnal types, obtained for energetic and tense arousal, be (1) replicated, (2) extended to elation and pleasantness, and (3) generalized to positive and negative affect? With regard to energetic arousal, all results were in line with those of Thayer and colleagues. However, regarding tense arousal, there was an unexpected main effect for time of day. For energetic arousal, elation, pleasantness, positive affect, and negative affect, there was (a) a significant main eflect for time of day, (b) a quadratic trend for diurnal variation, and (c) a significant Diurnal Type × Time of Day interaction, There were no significant sex differences in diurnal variation. Two final hypothetical statements are made about the diurnal variation and differences between diurnal types with regard to state scales: (a) the diurnal variation of a state scale cannot be described with a quadratic function if that scale is completely unrelated to energetic arousal; and (b) the characteristic differences between morning types and evening types, especially when measured in the morning and in the evening, will not manifest themselves on a state scale if that scale is entirely unrelated to energetic arousal. Finally, the possible usefulness of the results of this study for practical applications and the development of theories are discussed.  相似文献   
220.
The development of competence was studied in a longitudinal sample of 98 children, with measurement points when the children were 7, 10, and 12 years old. Competence was defined in terms of adequate adaptation to developmental tasks, both on a general and on a domain-specijic level. The general form of competence was measured by ego-resiliency, reflecting fexibility and ability to solve developmental problems Domain-specific competencies were measured by school achievement and social preference. The results showed that ego-resiliency was related to the two domain-specific competencies, although the hypothesized causal direction from general competence to specific competencies was not supported. Both domain-specific competencies were found to have a feedback effect on ego-resiliency. This feedback effect was stronger for social preference. These results suggest a transactional relationship between general and domain-specific competencies, and point to the importance of domain-specific competencies (especially social preference by the peer group) in the development of general competence in the child.  相似文献   
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