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891.
This study examined self-recognition processing in both the auditory and visual modalities by determining how comparable hearing a recording of one’s own voice was to seeing photograph of one’s own face. We also investigated whether the simultaneous presentation of auditory and visual self-stimuli would either facilitate or inhibit self-identification. Ninety-one participants completed reaction-time tasks of self-recognition when presented with their own faces, own voices, and combinations of the two. Reaction time and errors made when responding with both the right and left hand were recorded to determine if there were lateralization effects on these tasks. Our findings showed that visual self-recognition for facial photographs appears to be superior to auditory self-recognition for voice recordings. Furthermore, a combined presentation of one’s own face and voice appeared to inhibit rather than facilitate self-recognition and there was a left-hand advantage for reaction time on the combined-presentation tasks.  相似文献   
892.
Dynamic changes in neurochemistry, fiber architecture, and tissue composition occur in the adolescent brain. The course of these maturational processes is being charted with greater specificity, owing to advances in neuroimaging and indicate grey matter volume reductions and protracted development of white matter in regions known to support complex cognition and behavior. Though fronto-subcortical circuitry development is notable during adolescence, asynchronous maturation of prefrontal and limbic systems may render youth more vulnerable to risky behaviors such as substance use. Indeed, binge-pattern alcohol consumption and comorbid marijuana use are common among adolescents, and are associated with neural consequences. This review summarizes the unique characteristics of adolescent brain development, particularly aspects that predispose individuals to reward seeking and risky choices during this phase of life, and discusses the influence of substance use on neuromaturation. Together, findings in this arena underscore the importance of refined research and programming efforts in adolescent health and interventional needs.  相似文献   
893.
This study explores the social context of hereditary cancer risk perception in three families, an African-American family, a Mexican-American family, and a Caucasian family, each with Lynch Syndrome documented by a mismatch repair gene mutation. Communication network assessments measured family communication about cancer experiences and genetic testing information among a total of 26 participants. Participant narratives were evaluated to gain insight into how family cancer experiences and genetic testing information have shaped perceptions of cancer risk. Analysis of communication networks indicated that some families discussed cancer experiences to a greater extent than genetic testing information, and vice-versa. Interviews elucidated that sharing both types of health information led participants to conceptualize linkages among a strong family history of cancer, genetic testing information, and cancer prevention strategies. Understanding how different types of family communication influence the formation of perceived hereditary disease risk may enhance efforts to tailor genetic counseling services for families.  相似文献   
894.
It is well known that conversation (e.g, on a cell phone) impairs driving. We demonstrate that the reverse is also true: Language production and comprehension, and the encoding of the products of comprehension into memory, are less accurate when one is driving. Ninety-six pairs of drivers and conversation partners engaged in a story-retelling task in a driving simulator. Half of the pairs were older adults. Each pair completed one dual-task block (driving during the retelling task) and two single-task control blocks. The results showed a decline in the accuracy of the drivers’ storytelling and of their memory for stories that were told to them by their nondriving partners. Speech production suffered an additional cost when the difficulty of driving increased. Measures of driving performance suggested that the drivers gave priority to the driving task when they were conversing. As a result, their linguistic performance suffered.  相似文献   
895.
Anxiety is a common co-occurring problem among young people with autism spectrum disorders (ASD). Characterized by deficits in social interaction, communication problems, and stereotyped behavior and restricted interests, this group of disorders is more prevalent than previously realized. When present, anxiety may compound the social deficits of young people with ASD. Given the additional disability and common co-occurrence of anxiety in ASD, we developed a manual-based cognitive-behavioral treatment program to target anxiety symptoms as well as social skill deficits in adolescents with ASD [Multimodal Anxiety and Social Skills Intervention: MASSI]. In this paper, we describe the foundation, content, and development of MASSI. We also summarize data on treatment feasibility based on a pilot study that implemented the intervention.  相似文献   
896.
Children differ in how quickly they reach linguistic milestones. Boys typically produce their first multi‐word sentences later than girls do. We ask here whether there are sex differences in children’s gestures that precede, and presage, these sex differences in speech. To explore this question, we observed 22 girls and 18 boys every 4 months as they progressed from one‐word speech to multi‐word speech. We found that boys not only produced speech + speech (S+S) combinations (‘drink juice’) 3 months later than girls, but they also produced gesture + speech (G+S) combinations expressing the same types of semantic relations (‘eat’ + point at cookie) 3 months later than girls. Because G+S combinations are produced earlier than S+S combinations, children’s gestures provide the first sign that boys are likely to lag behind girls in the onset of sentence constructions.  相似文献   
897.
Data from three experiments provide the first evidence that children, at least as young as age two, are vigilant of others’ non‐verbal cues to credibility, and flexibly use these cues to facilitate learning. Experiment 1 revealed that 2‐ and 3‐year‐olds prefer to learn about objects from someone who appears, through non‐verbal cues, to be confident in performing actions on those objects than from someone who appears uncertain when performing actions on those objects. Experiment 2 revealed that when 2‐year‐olds observe only one model perform a single action, either confidently or unconfidently, they do not use the model’s level of confidence in this single instance to influence their learning. Experiment 3 revealed that 2‐year‐olds will use a single model’s level of confidence to guide their learning if they have observed that the model has a history of being either consistently confident or consistently uncertain. These findings reveal that young children selectively alter their learning based on others’ non‐verbal cues of credibility, and underscore the importance of an early sensitivity to socio‐cognitive cues for human learning and development.  相似文献   
898.
English, French, and bilingual English-French 17-month-old infants were compared for their performance on a word learning task using the Switch task. Object names presented a /b/ vs. /g/ contrast that is phonemic in both English and French, and auditory strings comprised English and French pronunciations by an adult bilingual. Infants were habituated to two novel objects labeled 'bowce' or 'gowce' and were then presented with a switch trial where a familiar word and familiar object were paired in a novel combination, and a same trial with a familiar word–object pairing. Bilingual infants looked significantly longer to switch vs. same trials, but English and French monolinguals did not, suggesting that bilingual infants can learn word–object associations when the phonetic conditions favor their input. Monolingual infants likely failed because the bilingual mode of presentation increased phonetic variability and did not match their real-world input. Experiment 2 tested this hypothesis by presenting monolingual infants with nonce word tokens restricted to native language pronunciations. Monolinguals succeeded in this case. Experiment 3 revealed that the presence of unfamiliar pronunciations in Experiment 2, rather than a reduction in overall phonetic variability was the key factor to success, as French infants failed when tested with English pronunciations of the nonce words. Thus phonetic variability impacts how infants perform in the switch task in ways that contribute to differences in monolingual and bilingual performance. Moreover, both monolinguals and bilinguals are developing adaptive speech processing skills that are specific to the language(s) they are learning.  相似文献   
899.
Animals are often assumed to use highly conspicuous features of a goal to head directly to that goal (‘beaconing’). In the field it is generally assumed that flowers serve as beacons to guide pollinators. Artificial hummingbird feeders are coloured red to serve a similar function. However, anecdotal reports suggest that hummingbirds return to feeder locations in the absence of the feeder (and thus the beacon). Here we test these reports for the first time in the field, using the natural territories of hummingbirds and manipulating flowers on a scale that is ecologically relevant to the birds. We compared the predictions from two distinct hypotheses as to how hummingbirds might use the visual features of rewards: the distant beacon hypothesis and the local cue hypothesis. In two field experiments, we found no evidence that rufous hummingbirds used a distant visual beacon to guide them to a rewarded location. In no case did birds abandon their approach to the goal location from a distance; rather they demonstrated remarkable accuracy of navigation by approaching to within about 70 cm of a rewarded flower’s original location. Proximity varied depending on the size of the training flower: birds flew closer to a previously rewarded location if it had been previously signalled with a small beacon. Additionally, when provided with a beacon at a new location, birds did not fly directly to the new beacon. Taken together, we believe these data demonstrate that these hummingbirds depend little on visual characteristics to beacon to rewarded locations, but rather that they encode surrounding landmarks in order to reach the goal and then use the visual features of the goal as confirmation that they have arrived at the correct location.  相似文献   
900.
Recent research has shown that domestic dogs are particularly good at determining the focus of human attention, often outperforming chimpanzees and hand-reared wolves. It has been suggested that the close evolutionary relationship between humans and dogs has led to the development of this ability; however, very few other domestic species have been studied. We tested the ability of 36 domestic horses to discriminate between an attentive and inattentive person in determining whom to approach for food. The cues provided were body orientation, head orientation or whether the experimenters’ eyes were open or closed. A fourth, mixed condition was included where the attentive person stood with their body facing away from the subjects but their head turned towards the subject while the inattentive person stood with their body facing the subject but their head turned away. Horses chose the attentive person significantly more often using the body cue, head cue, and eye cue but not the mixed cue. This result suggests that domestic horses are highly sensitive to human attentional cues, including gaze. The possible role of evolutionary and environmental factors in the development of this ability is discussed.  相似文献   
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