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991.
Psychonomic Bulletin & Review - Speech recognition is improved when the acoustic input is accompanied by visual cues provided by a talking face (Erber in Journal of Speech and Hearing Research,...  相似文献   
992.
Social Psychology of Education - Teacher turnover has been recognized as a significant problem in the education worldwide. This study focuses on exploring reasons behind the turnover intentions,...  相似文献   
993.
Animal Cognition - Colours are commonly used as visual cues when measuring animals’ cognitive abilities. However, animals can have innate biases towards certain colours that depend on...  相似文献   
994.
Animal Cognition - Errors of source monitoring are widespread human memory challenges, and our memories are subject to distortion upon the presentation of subsequent misinformation. Less is known...  相似文献   
995.
Applied Research in Quality of Life - This study identified associations between perceived neighborhood stress and adolescents’ perceptions of life satisfaction. African American adolescents...  相似文献   
996.

Previous studies have shown that participation in leisure time physical activity is related to better mental well-being and subjective health. However, the associations between different types of leisure time physical activities and different dimensions of mental well-being have rarely been studied. In addition, longitudinal research, analyzing possible causal relations between these variables, is lacking. To investigate these research questions, data gathered at ages 42 and 50 (present N = 303) for the Finnish Jyväskylä Longitudinal Study of Personality and Social Development were used. Physical activity was assessed as frequency of participation at ages 42 and 50, and at age 50 also as frequency of participation in different types of physical activities. Mental well-being was captured by emotional, psychological and social well-being and subjective health by self-rated health and symptoms. Cross-sectionally, different types of physical activities were related to different dimensions of well-being. Walking had positive associations with psychological and social well-being, rambling in nature with emotional and social well-being, and endurance training with subjective health. Rambling in nature was also positively related to subjective health but only among men. Longitudinally, mental well-being predicted later participation in leisure-time physical activity, whereas no longitudinal associations between subjective health and physical activity were found. The results suggest that leisure time physical activities are related to current mental well-being and subjective health in midlife. Across time, good mental well-being seems to be a resource promoting engagement in physical activity.

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997.
The role of conspecific chemical cues in the activation of sexual behavior was investigated in the female musk shrew (Suncus murinus). In Experiment 1, virgin female musk shrews were exposed to either clean cages or cages recently vacated by an adult male. Regardless of whether the male used for the sexual behavior test was "familiar" to the female (having spent the 24 h exposure in his vacant cage) or "unfamiliar," females exposed to male-related cues received mounts from males significantly sooner than females exposed to clean cages. In Experiment 2, females housed for 24 h in a cage soiled by an adult male allowed males to mount significantly sooner than females housed in a cage soiled by a castrated male, another female, or a clean cage. These results demonstrate that chemical cues, produced exclusively by adult males, promote sexual receptivity in female musk shrews.  相似文献   
998.
A recent study of the development of nonassociative learning in the siphon withdrawal reflex of Aplysia showed that dishabituation (facilitation of an habituated response) and sensitization (facilitation of a nonhabituated response) emerge according to different developmental timetables: dishabituation precedes sensitization by approximately 60 days (Rankin & Carew, 1988). Both forms of facilitation of the reflex were observed within 90 s of an electrical shock to the tail. However, more recent work by Marcus and colleagues (1988) in adult animals revealed that sensitization can have a delayed onset of 20-30 min after a strong tail shock. Since the developmental study of Rankin and Carew (1988) only tested the reflex for 10 min after tail shock, it is possible that sensitization was in fact present at earlier developmental stages, but was undetected. To examine this question, in the present study we utilized a longer (40-50 min) post-shock observation period to determine whether delayed-onset sensitization is exhibited in juvenile Aplysia, and if so, when it is expressed during development. In our first experiment, we found that Early Stage 12 juveniles (80-95 days after metamorphosis) showed significant delayed-onset sensitization 30-50 min after a strong tail shock. In a second experiment, we found that delayed-onset sensitization was absent in Stage 11 animals (20-70 days after metamorphosis). Thus delayed-onset sensitization emerges in Early Stage 12. The fact that the birthdate of delayed-onset sensitization is at least 30 days after that of dishabituation (Rankin & Carew, 1987, 1988) supports the hypothesis that these two forms of nonassociative learning may have at least partly different underlying mechanisms.  相似文献   
999.
Many regions around the third ventricle of the brain are thought to participate in the regulation of water intake. In this study we have visualized in acutely hyperosmolar mice the hypothalamic regions by using autoradiography and [14C]deoxyglucose as marker. By applying a recently published, inexpensive, calibrated photographic method for the analysis of the autoradiographs, we can show that the medial parts of the hypothalamus near the third ventricle increased their uptake of deoxyglucose in comparison with the lateral parts. Densitometric measurements confirmed the results. The results also indicate that parts of the medial hypothalamus, even those that are more caudal than the paraventricular nuclei, react to hyperosmolarity.  相似文献   
1000.
Male NMRI mice were given intravenous injections of the noradrenergic neurotoxin DSP4 or the vehicle 24 to 72 h prior behavioral testing. Animals were given 2 days of training on a one-way active avoidance task. Naloxone was given in one of three doses prior to training on Day 1 and Day 2 or prior to training on Day 1 only (saline was given prior to training on Day 2). There was a dose-dependent impairment of acquisition by naloxone in the vehicle-pretreated groups; 10 mg/kg naloxone produced a significant impairment of acquisition. Naloxone also modulated retention (Day 2) performance of the active avoidance task. For vehicle-pretreated mice, 1 mg/kg naloxone facilitated and 10 mg/kg naloxone-impaired performance on Day 2. DSP4 alone produced an impairment of acquisition of this task but had no effect on retention; Day 2 scores were slightly higher in the DSP4-pretreated group than in the vehicle-pretreated group. Naloxone produced somewhat different effects in DSP4-pretreated animals than in vehicle-pretreated animals. Naloxone (1 mg/kg) ameliorated the DSP4-induced impairment of acquisition; 10 mg/kg naloxone did not significantly alter the acquisition performance of this group. For the DSP4-pretreated mice that received naloxone before training on both days, the dose-response characteristics for retention scores were similar to those of vehicle-pretreated mice; 1 mg/kg naloxone was the facilitatory dose. However, for DSP4-treated mice that received naloxone before training on Day 1 only, there was a shift to the right in the effective facilitatory dose of naloxone. For these animals, 10 mg/kg naloxone but not 1 mg/kg naloxone significantly enhanced retention performance. We discuss these results in the context of a possible state-dependent modulation by naloxone in the DSP4-treated animals.  相似文献   
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