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981.
982.
The interrelationships between cigarette, alcohol, and coffee use were examined in 307 U.S. army trainees and 304 U.S. enlisted army personnel. Usage patterns indicated distinct gender differences in this occupational setting. Among women, cigarette use and alcohol consumption were positively correlated; whereas for men, cigarette and coffee use were positively related. For both males and females, alcohol and coffee use were only weakly correlated. As demonstrated in other studies, nonsmokers showed a consistent pattern of abstention from coffee and alcohol or moderate alcohol use.  相似文献   
983.
Because they were participating in a concurrent panel study, 222 older adults had been asked how much help they would expect to receive in a hypothetical emergency before experiencing two separate floods. For the subsample suffering losses or injuries during the floods, Study 1 examined the accuracy of their expectations, as well as possible changes in them, as a result of help actually received. Generally, victims received much less help than they had expected to receive prior to the floods. Preflood expectation of support predicted help from kin, whereas loss and education predicted help from nonkin sources. However, subsequent expectations did not change as a result of the level of help received. Using the total sample, Study 2 examined the broader issue of whether the disaster itself affected subsequent perceptions of support. Flood exposure, as measured at both individual and community levels, was associated with declines in perceptions of support and social participation.  相似文献   
984.
An overview is presented of a pilot psychoendocrine study of PTSD inpatients in comparison with several subgroups of schizophrenic and affective disorder patients. Using a hormonal profile including Cortisol, norepinephrine, epinephrine, testosterone, and thyroxine, it was found that the mean values for the PTSD group were at or near the extreme end of the range for every hormone measured, i.e., relatively low for Cortisol and high for the remaining hormones. The possible clinical meaning of these findings is considered in the light of prior psychoendocrine research on chronic stress. The hormonal alterations in PTSD appear to be persistent and suggest the possibility of being linked largely to traits or character structure, perhaps particularly to cognitive variables related to defense and coping mechanisms, as reviewed in detail for each hormonal system. There appears to be a potential for a fruitful union between the traumatic stress and psychoendocrine fields and some future strategies for developing and strengthening such a union are suggested.  相似文献   
985.
The temporal characteristics of repetitive finger tapping by the left and right hands were examined in two experiments. In the first experiment, interresponse intervals (IRIs) were recorded while right-handed male subjects tapped in synchrony with an auditory timing pulse (the synchronization phase) and then attempted to maintain the same tapping rate without the timing pulses (the continuation phase). The left and right hands performed separately, at four different rates (interpulse intervals of 250, 500, 750, and 1500 ms). There was no asymmetry of the asynchronies of the timing pulses and the associated responses in the synchronization phase or of the IRIs in either phase, but there was an asymmetry of chronization phase or of the IRIs in either phase, but there was an asymmetry in the temporal dispersion of the responses in both phases. in the second experiment, right-handed males tapped separately with each hand at three different speeds: as quickly as possible, at a fast but steady rate, and at a slow rhythmical rate. The speed asymmetry present when tapping as quickly as possible (with the preferred hand tapping more quickly ) was reduced when tapping at the fast steady rate and was absent when tapping at the slow rhythmical rate. The temporal dispersion of the IRIs produced by the nonpreferred hand was greater than the temporal dispersion of those produced by the preferred hand in all speed conditions. These results show smaller temporal dispersion of tapping by the preferred hand in right-handed males under different conditions, including submaximal speeds at which both hands respond at the same rate. This suggests that the motor system controlling the preferred hand in right-handers had more precise timing of response output than that controlling the nonpreferred hand.  相似文献   
986.
Monosynaptic Hoffman reflexes (H reflexes) were recorded from the soleus muscle during the response latency of a warned reaction time (RT) task that required plantarflexion of the foot. The task was done under four conditions of predictability of the response signal (RS), created by the factorial combination of foreperiod duration (1 and 4 s) and variability (fixed and variable). RT varied systematically with RS predictability and was facilitated in conditions that favored prediction of the RS. The response latency was divided into two successive phases by the onset of reflex augmentation: a premotor phase of constant reflex amplitude and a succeeding motor phase marked by progressively increasing reflex amplitude. Reflex augmentation during the motor phase was coupled more closely to the imminent movement than to the preceding signal to respond. The duration of the premotor phase was unaffected by RS predictability, but the duration of the motor phase (like RT) was shorter when the RS was more predictable. The maximum H reflex amplitude reached during the motor phase was greater when the RS was more predictable. The tonic level of H reflex amplitude during the premotor phase was greater in conditions that made prediction of the RS difficult. A second experiment showed that this difference was present throughout the foreperiod. These results suggest that conditions that favor prediction of the RS enhance motor preparation. changes in motor preparation (which affect RT) affect the processes underlying reflex amplitudes in the premotor phase and throughout the preceding foreperiod, in conditions that make prediction of the RS difficult, appear to reflect heightened general arousal.  相似文献   
987.
The present study investigates effects of different types of instructions (high-rate, interval, and minimal) during training with a fixed-interval schedule as a function of prior acquired temporal knowledge. A pretest was used to assess 4 1/2- and 6-year-old children's ability to understand the temporal parameters of a fixed-interval schedule of reinforcement. The results as a whole show that the control exerted by instructions given by the experimenter or elaborated by the subjects themselves on fixed-interval performance of young children depends on the interaction of two factors: development of verbal self-control skills and mastery of knowledge required by the rules forming the instructions.  相似文献   
988.
We analyzed the role of the range of variation in training exemplars as a contextual variable influencing the effects of in vivo versus simulation training in producing generalized responding. Four mentally retarded adults received single case instruction, followed by general case instruction, on washing machine and dryer use; one task was taught using actual appliances (in vivo) and the other using simulation. In vivo and simulation training were counterbalanced across the two tasks for the 2 subject pairs, using a within-subjects Latin square design. With both paradigms, more errors were made after single case than after general case instruction during probe sessions with untrained washing machines and dryers. These results suggest that generalization errors were affected by the range of training exemplars and not by the use of simulated versus natural training stimuli. Although both general case simulation and general case in vivo training facilitated generalized performance of laundry skills, an analysis of training time and costs indicated that the former approach was more efficient. The study illustrates a methodology for studying complex interactions and guiding decisions on the optimal use of instructional alternatives.  相似文献   
989.
Interactions of preschool and kindergarten friends and acquaintances   总被引:1,自引:0,他引:1  
The interactions of 4-, 5-, and 6-year-old friends and acquaintances in a peer teaching and game-playing situation were examined. The sample consisted of 102 children who were divided into pairs of same-age, same-sex friends or acquaintances using sociometrics. One child in each pair was randomly chosen to be the teacher and the other the learner. The teachers taught a novel board game to the learners. The most common teaching method was a combination of explaining and demonstrating the rules before the game began; older children gave more comprehensive instructions than younger children. At all ages, teachers were more likely than learners to take the first turn, issue commands, and change the rules. Friends were rated more involved with their partners, more emotionally expressive, and more competitive than acquaintances. Teachers who taught friends were rated more domineering than teachers who taught acquaintances, and learners who were taught by friends were rated more playful and friendly than learners taught by acquaintances.  相似文献   
990.
Purdue Pegboard performance of 16 male and 25 female right-handed college students were compared, and results were replicated with 25 male and 28 female subjects. In agreement with the literature, women performed significantly better than men. When measures of index finger and thumb thickness were used as covariate, all significant sex differences in performance disappeared. Negative correlations between performance and finger size were observed in both sexes. Sex differences in fine manual dexterity tasks may therefore be confounded by sex differences in finger size.  相似文献   
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