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891.
892.
Sexual infidelity can be costly to members of both the extra-pair and the paired couple. Thus, detecting infidelity risk is potentially adaptive if it aids in avoiding cuckoldry or loss of parental and relationship investment. Among men, testosterone is inversely related to voice pitch, relationship and offspring investment, and is positively related to the pursuit of short-term relationships, including extra-pair sex. Among women, estrogen is positively related to voice pitch, attractiveness, and the likelihood of extra-pair involvement. Although prior work has demonstrated a positive relationship between men?s testosterone levels and infidelity, this study is the first to investigate attributions of infidelity as a function of sexual dimorphism in male and female voices. We found that men attributed high infidelity risk to feminized women?s voices, but not significantly more often than did women. Women attributed high infidelity risk to masculinized men?s voices at significantly higher rates than did men. These data suggest that voice pitch is used as an indicator of sexual strategy in addition to underlying mate value. The aforementioned attributions may be adaptive if they prevent cuckoldry and/or loss of parental and relationship investment via avoidance of partners who may be more likely to be unfaithful.  相似文献   
893.
Most neural fibers of the cerebral cortex engage in electric signaling, but one particular fiber, the apical dendrite of the pyramidal neuron, specializes in electric resonating. This dendrite extends upward from somas of pyramidal neurons, the most numerous neurons of the cortex. The apical dendrite is embedded in a recurrent corticothalamic circuit that induces surges of electric current to move repeatedly down the dendrite. Narrow bandwidths of surge frequency (resonating) enable cortical circuits to use specific carrier frequencies, which isolate the processing of those circuits from other circuits. Resonating greatly enhances the intensity and duration of electrical activity of a neuron over a narrow frequency range, which underlies attention in its various modes. Within the minicolumn, separation of the central resonating circuit from the surrounding signal processing network separates “having” subjective impressions from “thinking about” them. Resonating neurons in the insular cortex apparently underlie cognitive impressions of feelings.  相似文献   
894.
ObjectivesLittle is known about the mechanisms that might mediate the relationship between transformational leadership behaviors and follower outcomes in the sporting domain. The purpose of this study was to examine whether intrateam communication mediated the effects of transformational leadership behaviors on task cohesion.Design/MethodsA cross-sectional study of university level ultimate frisbee players (N = 199). Participants completed a measure assessing their perceptions of their captain's transformational leadership behaviors. Post-competition, participants completed measures assessing perceptions of intrateam communication and task cohesion within their own team.ResultsMultilevel analyses revealed intrateam communication to partially mediate the relationships between two of the transformational leadership behaviors and task cohesion.ConclusionsIntrateam communication is seen to be a mechanism that explains the relationship between transformational leadership and task cohesion. Overall, the results support and add to the range of positive effects associated with transformational leadership in sport, and are suggestive of interventions that may raise levels of team cohesion.  相似文献   
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897.
Optimal cognitive ability is likely important for military working dogs (MWD) trained to detect explosives. An assessment of a dog’s ability to rapidly learn discriminations might be useful in the MWD selection process. In this study, visual discrimination and reversal tasks were used to assess cognitive performance in Labrador retrievers selected for an explosives detection program using a modified version of the Toronto General Testing Apparatus (TGTA), a system developed for assessing performance in a battery of neuropsychological tests in canines. The results of the current study revealed that, as previously found with beagles tested using the TGTA, Labrador retrievers (N = 16) readily acquired both tasks and learned the discrimination task significantly faster than the reversal task. The present study confirmed that the modified TGTA system is suitable for cognitive evaluations in Labrador retriever MWDs and can be used to further explore effects of sex, phenotype, age, and other factors in relation to canine cognition and learning, and may provide an additional screening tool for MWD selection.  相似文献   
898.
We hypothesized that semantic memory for object concepts involves both representations of visual feature knowledge in modality-specific association cortex and heteromodal regions that are important for integrating and organizing this semantic knowledge so that it can be used in a flexible, contextually appropriate manner. We examined this hypothesis in an fMRI study of mild Alzheimer’s disease (AD). Participants were presented with pairs of printed words and asked whether the words matched on a given visual–perceptual feature (e.g., guitar, violin: SHAPE). The stimuli probed natural kinds and manufactured objects, and the judgments involved shape or color. We found activation of bilateral ventral temporal cortex and left dorsolateral prefrontal cortex during semantic judgments, with AD patients showing less activation of these regions than healthy seniors. Moreover, AD patients showed less ventral temporal activation than did healthy seniors for manufactured objects, but not for natural kinds. We also used diffusion-weighted MRI of white matter to examine fractional anisotropy (FA). Patients with AD showed significantly reduced FA in the superior longitudinal fasciculus and inferior frontal-occipital fasciculus, which carry projections linking temporal and frontal regions of this semantic network. Our results are consistent with the hypothesis that semantic memory is supported in part by a large-scale neural network involving modality-specific association cortex, heteromodal association cortex, and projections between these regions. The semantic deficit in AD thus arises from gray matter disease that affects the representation of feature knowledge and processing its content, as well as white matter disease that interrupts the integrated functioning of this large-scale network.  相似文献   
899.
Although content analyses have found that superhero programs in the media portray strong gender stereotypes of masculinity, little research has examined the effects of viewing such programs. In the current study, 134 mothers of preschool children (from the Western and Northwestern United States) reported their child’s superhero exposure in the media, male-stereotyped play, weapon play, and parental active mediation of the media at two time points (1 year apart). Results revealed that boys viewed superhero programs more frequently than girls, with nearly a quarter of boys viewing superhero programs at least weekly. Analyses revealed that superhero exposure was related to higher levels of male-stereotyped play for boys and higher levels of weapon play for both boys and girls from Time 1 to Time 2, even after controlling for initial levels. Parental active mediation did not negate these effects, and even served to strengthen one finding for girls. Specifically, among girls with high superhero exposure, weapon play was highest for girls who received frequent active mediation. Implications of the results are discussed with a focus on whether such programs are developmentally appropriate for preschool children.  相似文献   
900.
David Barrett 《Synthese》2014,191(12):2695-2714
Piccinini and Craver (Synthese 183:283–311, 2011) argue for the surprising view that psychological explanation, properly understood, is a species of mechanistic explanation. This contrasts with the ‘received view’ (due, primarily, to Cummins and Fodor) which maintains a sharp distinction between psychological explanation and mechanistic explanation. The former is typically construed as functional analysis, the analysis of some psychological capacity into an organized series of subcapacities without specifying any of the structural features that underlie the explanandum capacity. The latter idea, of course, sees explanation as a matter of describing structures that maintain (or produce) the explanandum capacity. In this paper, I defend the received view by criticizing Piccinini and Craver’s argument for the claim that psychological explanation is not distinct from mechanistic explanation, and by showing how psychological explanations can possess explanatory force even when nothing is known about the underlying neurological details. I conclude with a few brief criticisms about the enterprise of mechanistic explanation in general.  相似文献   
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