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951.
In this study, associations were examined between cortisol levels of wives and husbands in 47 heterosexual married couples. Both partners' salivary cortisol levels were measured at the same moments seven times a day on 2 typical weekdays. After accounting for the effects of the diurnal rhythm of cortisol and relevant control variables, dyadic hierarchical linear modeling indicated significant positive linkages between partners' cortisol levels, consistent with the hypothesized within‐couple physiological synchrony. Variables reflecting more (spousal presence) or less connectedness (loneliness, being alone) were also collected at the time of each cortisol sample. Results indicated that husbands' cortisol levels were higher at moments they reported feeling lonelier and lower at moments they were in the presence of their spouse. Wives' cortisol levels were higher at moments they were alone. In addition, wife–husband cortisol synchrony was stronger for husbands who spent relatively more time with their spouse across the study period—even after accounting for time spent with others in general. These findings suggest that marital partners evidence positive within‐couple cortisol associations, and that connectedness (particularly physical closeness) may underpin spouses' physiological synchrony.  相似文献   
952.
Little longitudinal research has been conducted on changes in children's emotional self-regulation strategy (SRS) use after infancy, particularly for children at risk. In this study, the authors examined changes in boys’ emotional SRS from toddlerhood through preschool. Repeated observational assessments using delay of gratification tasks at ages 2, 3, and 4 years were examined with both variable- and person-oriented analyses in a low-income sample of boys (N = 117) at risk for early problem behavior. Results were consistent with theory on emotional SRS development in young children. Children initially used more emotion-focused SRS (e.g., comfort seeking) and transitioned to greater use of planful SRS (e.g., distraction) by 4 years of age. Person-oriented analysis using trajectory analysis found similar patterns from 2 to 4 years, with small groups of boys showing delayed movement away from emotion-focused strategies or delay in the onset of regular use of distraction. The results provide a foundation for future researchers to examine the development of SRS in low-income young children.  相似文献   
953.

Objective

Contrasts of verbal fluency and automatic speech provide an opportunity to evaluate the neural underpinnings of generativity and flexibility in autism spectrum disorders (ASD).

Method

We used functional magnetic resonance imaging (fMRI) to contrast brain activity in high functioning ASD (n = 17, mean verbal IQ = 117) and neurotypical (NT; n = 20, mean verbal IQ = 112) adolescent and young adult males (12–23 years). Participants responded to three word generation conditions: automatic speech (reciting months), category fluency, and letter fluency.

Results

Our paradigm closely mirrored behavioral fluency tasks by requiring overt, free recall word generation while controlling for differences in verbal output between the groups and systematically increasing the task demand. The ASD group showed reduced neural response compared to the NT participants during fluency tasks in multiple regions of left anterior and posterior cortices, and sub-cortical structures. Six of these regions fell in cortico-striatal circuits previously linked to repetitive behaviors (Langen, Durston, Kas, van Engeland, & Staal, 2011), and activity in two of them (putamen and thalamus) was negatively correlated with autism repetitive behavior symptoms in the ASD group. In addition, response in left inferior frontal gyrus was differentially modulated in the ASD, relative to the NT, group as a function of task demand.

Conclusions

These data indicate a specific, atypical brain response in ASD to demanding generativity tasks that may have relevance to repetitive behavior symptoms in ASD as well as to difficulties generating original verbal responses.  相似文献   
954.
The "ba, ba, ba" sound universal to babies' babbling around 7 months captures scientific attention because it provides insights into the mechanisms underlying language acquisition and vestiges of its evolutionary origins. Yet the prevailing mystery is what is the biological basis of babbling, with one hypothesis being that it is a non-linguistic motoric activity driven largely by the baby's emerging control over the mouth and jaw, and another being that it is a linguistic activity reflecting the babies' early sensitivity to specific phonetic-syllabic patterns. Two groups of hearing babies were studied over time (ages 6, 10, and 12 months), equal in all developmental respects except for the modality of language input (mouth versus hand): three hearing babies acquiring spoken language (group 1: "speech-exposed") and a rare group of three hearing babies acquiring sign language only, not speech (group 2: "sign-exposed"). Despite this latter group's exposure to sign, the motoric hypothesis would predict similar hand activity to that seen in speech-exposed hearing babies because language acquisition in sign-exposed babies does not involve the mouth. Using innovative quantitative Optotrak 3-D motion-tracking technology, applied here for the first time to study infant language acquisition, we obtained physical measurements similar to a speech spectrogram, but for the hands. Here we discovered that the specific rhythmic frequencies of the hands of the sign-exposed hearing babies differed depending on whether they were producing linguistic activity, which they produced at a low frequency of approximately 1 Hz, versus non-linguistic activity, which they produced at a higher frequency of approximately 2.5 Hz - the identical class of hand activity that the speech-exposed hearing babies produced nearly exclusively. Surprisingly, without benefit of the mouth, hearing sign-exposed babies alone babbled systematically on their hands. We conclude that babbling is fundamentally a linguistic activity and explain why the differentiation between linguistic and non-linguistic hand activity in a single manual modality (one distinct from the human mouth) could only have resulted if all babies are born with a sensitivity to specific rhythmic patterns at the heart of human language and the capacity to use them.  相似文献   
955.
Olfactory perceptual learning is a relatively long-term, learned increase in perceptual acuity, and has been described in both humans and animals. Data from recent electrophysiological studies have indicated that olfactory perceptual learning may be correlated with changes in odorant receptive fields of neurons in the olfactory bulb and piriform cortex. These changes include enhanced representation of the molecular features of familiar odors by mitral cells in the olfactory bulb, and synthetic coding of multiple coincident odorant features into odor objects by cortical neurons. In this paper, data are reviewed that show the critical role of acetylcholine (Ach) in olfactory system function and plasticity, and cholinergic modulation of olfactory perceptual learning at both the behavioral and cortical level.  相似文献   
956.
We used the Rasch (1980) model to develop new pictures for the Thematic Apperception Test (C. D. Morgan & Murray, 1938; McClelland, Atkinson, Clark, & Lowell, 1953) or picture story exercise to measure need for achievement (nAch). In Experiments 1 and 2, we analyzed stories to assess the difficulty level of a total of 8 pictures using the multifaceted Rasch model with picture difficulty, story probe difficulty, and participant ability as facets with a partial credit model (FACETS; Linacre, 2005). A total of 6 pictures were retained and 4 new ones added for Experiment 3 in which 201 participants wrote 6 stories to a random set of the 10 pictures. FACETS analysis revealed improved person separation reliability. In Experiment 4, 206 participants wrote 1 story to the Studying picture either before or after filling out a battery of achievement-related questionnaires. The 2 experimental groups did not differ in the amount of nAch in their stories. The coder facet was demonstrated with 2 independent coders using the revised coding system for nAch.  相似文献   
957.
Objective: An enhanced stress and coping model was used to explain depression among HIV-positive women in healthcare and community settings where highly active anti-retroviral treatment (HAART) was commonplace. Method: HIV-infected women in four cities (N=978) were assessed, cross-sectionally, for mental and physical health, stress, social support, and other background factors. Results: Self-reported level of depressive symptomatology was high. Number of physical symptoms, illness intrusiveness, and perceived stress were positively associated with depressed mood, while coping self-efficacy and social support were negatively associated. Stress mediated the effect of health status on depression and coping self-efficacy mediated the effect of psychosocial resources on depression. Our enhanced stress and coping model accounted for 52% of variance in depressive symtpomatology. Conclusions: Interventions focused on improving coping self-efficacy, bolstering social supports, and decreasing stress in the lives of HIV-positive women may help to reduce the negative effects of HIV disease on mood.  相似文献   
958.
Language and communication deficits are core features of autism spectrum disorders (ASD), even in high-functioning adults with ASD. This study investigated brain activation patterns using functional magnetic resonance imaging in right-handed adult males with ASD and a control group, matched on age, handedness, and verbal IQ. Semantic processing in the controls produced robust activation in Broca's area (left inferior frontal gyrus) and in superior medial frontal gyrus and right cerebellum. The ASD group had substantially reduced Broca's activation, but increased left temporal (Wernicke's) activation. Furthermore, the ASD group showed diminished activation differences between concrete and abstract words, consistent with behavioral studies. The current study suggests Broca's area is a region of abnormal neurodevelopment in ASD, which may be linked with semantic and related language deficits frequently observed in ASD.  相似文献   
959.
In two experiments, we explored how novice and expert athletes represent the everyday and sportspecific objects and actions that they read about. Novice and expert ice hockey players (Experiment 1) and football players (Experiment 2) read sentences describing everyday or sport-specific situations and then judged whether a pictured item (either matching the action implied in the previous sentence or not) was mentioned in the preceding sentence. The sentences in Experiment 1 consisted of everyday and hockey-specific scenarios. The sentences in Experiment 2 depicted football scenarios implying football-specific or non—football-specific actions anyone might perform. Everyone responded most quickly to items that matched the sentence-implied actions for everyday and non—sport-specific actions. Only athletes showed this effect for their respective sport-specific scenarios. Differentiating between the same item in different action orientations is thought to be driven by embodied knowledge containing the sensorimotor characteristics of what one is reading about. We show that possessing this type of representation depends on experience interacting with objects and performing the actions in question.  相似文献   
960.
Although environmental enrichment improves spatial memory and alters synaptic plasticity in aged rodents, it is unclear whether all types of enrichment treatments yield similar benefits. The present study examined the effects in aged male mice of three types of enrichment on spatial memory in Morris water maze and radial arm maze tasks, and on levels of the presynaptic protein synaptophysin in several brain regions. Non-enriched young and aged males were compared with males exposed to one of the following treatments for 10 weeks: 5 min of daily handling, 3 h of daily basic enrichment, or 24 h of continuous complex enrichment. Young controls outperformed aged controls in both tasks. Neither daily handling nor daily enrichment affected spatial memory or synaptophysin levels. In contrast, continuous enrichment significantly reduced age-related spatial memory decline in both tasks, such that this group was statistically indistinguishable from young controls in most measures of performance. Continuously enriched mice were also significantly better than other aged mice in several spatial memory measures. Despite these improvements, synaptophysin levels in the continuous enrichment group were significantly lower than those of young and aged controls in the frontoparietal cortex, hippocampus, and striatum, suggesting a negative relationship between synaptophysin levels and spatial memory in aged males. These data demonstrate that different types of enrichment in aged male mice have disparate effects on spatial memory, and that the relationship between enrichment-induced changes in synaptophysin levels and spatial memory in aged males differs from that we have previously reported in aged female mice.  相似文献   
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