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101.
Young and older adults' eye fixations were monitored as they read sentences with temporary ambiguities such as "The experienced soldiers warned about the dangers conducted the midnight raid." Their fixation patterns were similar except that older adults made many regressions. In a 2nd experiment, high- and low-span older adults were compared with high- and low-span young adults. Pint-pass fixations were similar, except low-span readers made many regressions and their total fixation times were longer. High-span readers also used the focus operator "only" (e.g., "Only experienced soldiers warned about the dangers.") to immediately resolve the temporary ambiguities. No age group differences were observed. These results are discussed with reference to theories of the role of working memory in sentence processing.  相似文献   
102.
The authors examined the role of family factors and the course of schizophrenia by carrying out additional assessments and analyses in 2 previously published studies of Mexican American and Anglo American patients and families. The authors found partial support for an attributional model of relapse for families who are low in emotional overinvolvement. Attributions of control, criticism, and warmth together marginally predicted relapse. The data also indicated that for Mexican Americans, family warmth is a significant protective factor, whereas for Anglo Americans, family criticism is a significant risk factor. These findings suggest that the sociocultural context shapes the pathways by which family processes are related to the course of illness. Moreover, the warmth findings suggest that families may contribute to preventing relapse.  相似文献   
103.
People differ in the extent to which they emphasize feelings of activation or deactivation in their verbal reports of experienced emotion, termed arousal focus (AF). Two multimethod studies indicate that AF is linked to heightened interoceptive sensitivity (as measured by performance on a heartbeat detection task). People who were more sensitive to their heartbeats emphasized feelings of activation and deactivation when reporting their experiences of emotion over time more than did those who were less sensitive. This relationship was not accounted for by several other variables, including simple language effects. Implications for the role of interoception in experienced emotion and the validity of self-reported emotion are discussed.  相似文献   
104.
Coherent visual experience requires not only segmenting incoming visual input into a structured scene of objects, but also binding discrete views of objects into dynamic representations that persist across time and motion. However, surprisingly little work has explored the principles that guide the construction and maintenance of such persisting object representations. What causes a part of the visual field to be treated as the same object over time? In the cognitive development literature, a key principle of object persistence is cohesion: An object must always maintain a single bounded contour. Here we demonstrate for the first time that mechanisms of adult midlevel vision are affected by cohesion violations. Using the object-file framework, we tested whether object-specific preview benefits-a hallmark of persisting object representations-are obtained for dynamic objects that split into two during their motion. We found that these preview benefits do not fully persist through such cohesion violations without incurring significant performance costs. These results illustrate how cohesion is employed as a constraint that guides the maintenance of object representations in adult midlevel vision.  相似文献   
105.
Positron emission tomography was used to investigate whether the motor-iconic basis of certain forms in American Sign Language (ASL) partially alters the neural systems engaged during lexical retrieval. Most ASL nouns denoting tools and ASL verbs referring to tool-based actions are produced with a handshape representing the human hand holding a tool and with an iconic movement depicting canonical tool use, whereas the visual iconicity of animal signs is more idiosyncratic and inconsistent across signs. We investigated whether the motor-iconic relation between a sign and its referent alters the neural substrate for lexical retrieval in ASL. Ten deaf native ASL signers viewed photographs of tools/utensils or of actions performed with or without an implement and were asked to overtly produce the ASL sign for each object or action. The control task required subjects to judge the orientation of unknown faces. Compared to the control task, naming tools engaged left inferior and middle frontal gyri, bilateral parietal lobe, and posterior inferotemporal cortex. Naming actions performed with or without a tool engaged left inferior frontal gyrus, bilateral parietal lobe, and posterior middle temporal gyrus at the temporo-occipital junction (area MT). When motor-iconic verbs were compared with non-iconic verbs, no differences in neural activation were found. Overall, the results indicate that even when the form of a sign is indistinguishable from a pantomimic gesture, the neural systems underlying its production mirror those engaged when hearing speakers name tools or tool-based actions with speech.  相似文献   
106.
Cerebellar volumes show small positive correlations with cognitive ability in young adults, but no studies have examined this relationship in older adults. Furthermore, no studies have examined relationships between sizes of subareas of the cerebellum and cognitive ability. We hypothesized that size of the two areas of the neocerebellar vermis would correlate with a battery of eight cognitive tests in 50 men aged 65-70. Size of the neocerebellar areas of the vermis correlated positively with several cognitive tests (r's=.29-.37, p<.05), whilst sizes of other parts of the vermis did not correlate with any cognitive tests. Total cerebellar volumes correlated significantly with a test of nonverbal reasoning (r=.030, p=.42). These findings suggest a specific association of neocerebellar vermis size with variations in cognitive ability in older adults.  相似文献   
107.
108.
This study describes the effects of different weekly work intensity levels on adolescent functioning in a sample of 3,083 high school students in rural South Texas, where economically disadvantaged and Hispanic youth are heavily represented. Anonymous surveys were conducted in 10th- and 12th-grade students' classrooms in 1995. The following effects were associated with long hours of weekly employment during the school year: (1) decreased performance/engagement in school and satisfaction with amount of leisure time, and (2) increased health risk behaviors and psychological stress. The effects of school-year work on academic factors and health behaviors differed by grade, but not by race/ethnicity, parent education, or race/ethnicity and parent education considered together. It was concluded that parents and professionals should continue to monitor the number of weekly hours that students work during the school year.  相似文献   
109.
Because studies examining the emotional impact of infertility-related stress generally focus on individuals, there has been little research examining how relationship and individual variables are linked. The purpose of this study was to explore the impact of congruence (e.g., agreement) between partner's perceived infertility-related stress and its effects on depression and marital adjustment in infertile men and women. Couples referred for infertility treatments at a University-affiliated teaching hospital completed the Fertility Problem Inventory (FPI), the Beck Depression Inventory (BDI), and the Dyadic Adjustment Scale (DAS) 3 months prior to their first treatment cycle. Study findings show that men and women in couples who perceived equal levels of social infertility stress reported higher levels of marital adjustment when compared to men and women in couples who perceived the stress differently. In addition, women in couples who felt a similar need for parenthood reported significantly higher levels of marital satisfaction when compared to women in couples where the males reported a greater need for parenthood. While couple incongruence was unrelated to depression in males, incongruence over relationship concerns and the need for parenthood was related to female depression. These findings provide initial support for the theory that high levels of agreement between partners related to the stresses they experience help them successfully manage the impact of these stressful life events. Possibilities for future research examining the construct of couple congruence are discussed.  相似文献   
110.
Although reactivation and reinstatement reminders differ procedurally, differences in their memory-preserving effects have been described as artifactual. In three experiments, we examined this conclusion. One hundred and twelve 6-month-olds learned an operant task, forgot it, received a reactivation or reinstatement reminder to recover the inactive memory, and were tested after increasing delays until they forgot it again. In Experiments 1a and 1b, a single reactivation reminder extended infants' memory of an operant mobile task for 2 weeks after reminding, but a single reinstatement extended it for 4 weeks, when testing was discontinued. In Experiment 2, a single reinstatement extended 6-month-olds' memory of an operant train task for 19 weeks after reminding, when infants were almost 1 year old. After reactivation, infants remember this task for only 2 weeks. The finding that the memory-preserving effect of reinstatement is greater by an order of magnitude suggests that procedural differences between the two reminders have functional significance.  相似文献   
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