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131.
    
The current 8‐year panel study explored changes in marital satisfaction among 614 married middle‐aged persons with seventh‐grade children. It also examined how individual health (physical health and depressive moods) and role changes (parenting transitions and life stress) were related to trajectories of marital satisfaction and investigated the buffering effect of family cohesion on these associations. Growth curve analyses show an inverted‐U shape in marital satisfaction during middle age. This indicates that regardless of the gender or age of the respondents, marital satisfaction among middle‐aged adults increased when their children were in the 9th and 12th grade, and then declined when their children were in their sophomore year of college. Declining physical health and an increase in depressive moods were related to a drop in marital satisfaction. Stressful events in midlife had negative effects on marital satisfaction, and family cohesion served as a buffer to mitigate the adverse impact of life stress on marital satisfaction. Overall, these results highlight the role of adolescent children in understanding why marital satisfaction changes among middle‐aged parents and emphasize the importance of health and life stress in relation to midlife marital satisfaction. These findings are discussed with life course perspectives and Taiwanese cultural values in relation to familism and academic achievement among children.  相似文献   
132.
    
Most studies of molecular mechanisms of synaptic plasticity have focused on the sequence of changes either at individual synapses or in the cell nucleus. However, studies of long-term facilitation at Aplysia sensory neuron–motor neuron synapses in isolated cell culture suggest two additional features of facilitation. First, that there is also regulation of the number of synaptic contacts between two neurons, which may occur at the level of cell pair-specific branch points in the neuronal arbor. Branch points contain many molecules that are involved in protein synthesis-dependent long-term facilitation including neurotrophins and the RNA binding protein CPEB. Second, the regulation involves homeostatic feedback and tends to keep the total number of contacts between two neurons at a fairly constant level both at rest and following facilitation. That raises the question of how facilitation and homeostasis can coexist. A possible answer is suggested by the findings that they both involve spontaneous transmission and postsynaptic Ca2+, which can have bidirectional effects similar to LTP and LTD in hippocampus. In addition, long-term facilitation can involve a change in the set point of homeostasis, which could be encoded by plasticity molecules such as CPEB and/or PKM. A computational model based on these ideas can qualitatively simulate the basic features of both facilitation and homeostasis of the number of contacts.

Synaptic plasticity is a change in strength of the synaptic connection (postsynaptic potential or PSP) between neurons and includes increases during facilitation and decreases during depression. Plasticity is thought to underlie circuit formation during development and learning and memory in adults, and correspondingly to be defective in neurodevelopmental disorders including autism, ADHD, and schizophrenia as well as learning and memory disorders including Alzheimer''s, age-related memory loss, and drug addiction (Hawkins 2013; Hawkins et al. 2017). Most studies of molecular mechanisms of synaptic plasticity have focused on either changes at individual synapses or gene regulation in the cell nucleus. However, studies of long-term facilitation at Aplysia sensory neuron–motor neuron (SN–MN) synapses in isolated cell culture (Glanzman et al. 1990), sensitization in the intact animal (Wainwright et al. 2004), and long-term potentiation in hippocampal neurons (Antonova et al. 2001, 2009) have shown that there are also changes in the number of contacts between presynaptic varicosities and the postsynaptic neuron. We refer to these as synaptic contacts although not all of them are functional synapses (Kim et al. 2003). The number of contacts is thought to be an important determinant of the strength of the PSP (Zhang et al. 2003) and to be different for different neuron pairs. It also increases during long-term facilitation of the PSP and is thought to be a major determinant of the time course of the facilitation (Bailey and Chen 1989).As in other systems (Antonova et al. 2001, 2009; Holtmaat and Svoboda 2009), the contacts are dynamic and are continually being formed and eliminated, but the total number and the PSP remain fairly constant both at rest and during long-term facilitation (Miniaci et al. 2008; Chen et al. 2014). Furthermore, the number of contacts and the PSP return to baseline when maintenance of the facilitation is blocked, but the individual contacts are not all the same as they were before facilitation. These results have led some to suggest that memories are not stored at individual synaptic contacts, as is often supposed, but rather are stored in the nucleus (Chen et al. 2014). However, most of the previous experiments have involved a single SN and a single MN, so it has not been possible to examine the synapse specificity of the effects. Experiments with one SN and two MNs (Martin et al. 1997) or two SNs and 1 MN (Schacher et al. 1997) have shown that facilitation of the number of synaptic contacts and the PSP is specific to the stimulated synaptic pair (e.g., SN–MN1) and does not occur for the other pair (e.g., SN–MN2). These results should generalize to multiple pre- and postsynaptic partners and suggest two novel features of synaptic regulation during plasticity: (1) that the number of synaptic contacts between two neurons is regulated, and (2) that the regulation is homeostatic. We first describe those features and some of the evidence supporting them, then propose a model that could account for them and present computational modeling to illustrate the plausibility of the model.  相似文献   
133.
    
The present research explored the selfishness of power and status as well as the mechanism in Chinese work situations. By using experimental and survey methods, two studies were designed to investigate the relationships among power, status, and self‐interested behaviour (SIB) as well as the mediating effect of perspective‐taking (PT). Results of the two studies consistently indicated that power increases whereas status reduces SIB. These opposing behavioural effects are partially attributed to the fact that power reduces whereas status increases PT. In addition, our results showed an interaction between power and status on SIB in Study 1 (interaction as a mental function), and a positive correlation between perceived power and status in Study 2 (correlation as a mental perception). Through the discussion from the perspective of the self/other‐orientation trait, as well as the stable effects of power and status on SIB in the two studies, we conclude that power is selfish and status is unselfish in Chinese work situations.  相似文献   
134.
    
A Multiple Indicators Multiple Causes (MIMIC) approach was applied to investigate the relationship between virtues and positive mental health as determined using the Character Strength Test and the Mental Health Continuum‐Short Form. The study participants were 876 college students (54% women; overall mean age [SD] 21.50 years [2.35]) recruited from introductory psychology courses at two universities in Seoul. Findings revealed that the intellectual virtues of college students predicted subjective well‐being according to all emotional, social and psychological measures. Results are discussed in the context of previous work using the Values in Action classification of virtues and character strengths. In addition, implications regarding understanding the nature and possible origins of positive mental health are outlined.  相似文献   
135.
We conducted three studies to investigate indulgent choice in settings with and without impression management by public–private manipulation with evaluation. Study 1 showed that the participants were less indulgent under public scrutiny due to the employment of impression management. Study 2 focused on the impression management context to test the moderate effect of self‐consciousness in two impression managed contexts. Study 3 focused on context without impression management to test the moderate effects of self‐awareness on choices. We found that depending on differences in primed personality, individuals tended to make choices other than those they favoured privately when anticipating that others might form impressions of them based on the decisions made. The findings of all three studies support our basic prediction that people are less indulgent under impression management and suggest that people tend to manage their impression by eating healthier (less indulgently) in public.  相似文献   
136.
    
To enhance the predictive validity of self-report personality measures, 2 distinct ways of increasing specificity of personality measures have been proposed in the literature—contextual specificity (i.e., providing a contextual referent) and content specificity (i.e., focusing on more specific constructs such as the Big Five facets). This study extends this line of research by examining whether there is an optimal way to configure, align, or integrate contextual and content specificity using measures of conscientiousness to predict college student success. A sample of 478 undergraduate students completed 4 measures of conscientiousness that varied in the level of content and contextual specificity. These forms of specificity were crossed to yield 4 distinct measures of conscientiousness. We then evaluated and compared the relative importance and the incremental importance of these different measures in the prediction of academic success. Superior predictive validity was found for both contextualized and facet measures of conscientiousness compared to a measure of global conscientiousness in predicting grade-point average and a broader behavioral criterion of student performance. When contextual and content specificity approaches were compared and combined, we observed the strongest predictive validity when the level of specificity is appropriately matched between predictor and criterion.  相似文献   
137.
    
ABSTRACT

This research was designed to test the hypothesis that motor practice can enhance the capabilities of motor control in healthy controls (NC) and patients with a diagnosis of probable Alzheimer's disease (AD) and mild cognitive impairment (MCI), and consequently results in better motor performance. Approximately half of the subjects in the NC (n = 31), AD (n = 28), and MCI (n = 29) either received or did not receive practice on a task of fast and accurate arm movement with a digitizer. Changes in movement time (MT), movement smoothness (jerk), and percentage of primary submovement (PPS) were recorded and compared among the three groups across six blocks of trials (baseline and five training sessions). For all subjects, practice improved motor functions as reflected by faster and smoother motor execution, as well as a greater proportion of programming control. Compared to unaffected matched controls, AD and MCI subjects exhibited a greater reduction in movement jerk due to practice. Movement time and PPS data revealed that motor practice appeared to reduce the use of “on-line” correction adopted by the AD or MCI patients while performing the aiming movements. Evidently, their arm movements were quicker, smoother, and temporally more consistent than their untrained peers. The findings of this study shed light on how MCI and AD may affect motor control mechanisms, and suggest possible therapeutic interventions aimed at improving motor functioning in these impaired individuals.  相似文献   
138.
    
Radiologists often miss nodules that may represent lung cancer on chest radiographs. We investigated whether eye movements collected during the search for lung nodules by large samples of laypeople may provide information that could assist radiologists in their detection. For that purpose, we developed a partially invisible Markov model with partially unobserved states and analyzed eye tracking data of over 100 laypeople who reviewed 14 chest X‐ray images, of which seven contained a potentially cancerous nodule. We used the luminance value of the pixels in the X‐ray images as prior information on the possible location of a nodule and identified six regions of interest on each image that may contain a nodule. Our study demonstrated that the eye movements recorded from laypersons contained information that may assist radiologists in the detection of nodules in chest X‐rays, which has important implications for crowdsourcing of search for pulmonary nodules, which are discussed. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
139.
    
Auditory distractions can have serious consequences in critical situations such as driving. Mobile phones, radios, media players, and information devices that interpret and produce speech are increasingly common in vehicles, but the threats to visual attention are not yet fully understood. In three experiments, we found that most speech tasks had relatively small adverse effects on the detection of a briefly presented target among distractors across a 60° subarea of the visual field. Although there was a little impact on detectability, moderately difficult speech tasks slowed responding relative to silence. Our most demanding condition—generating and speaking a word beginning with the last letter of another word—had the greatest effects on accuracy and latency, with responding slowed by about 900 ms. An impairment of this magnitude presents a significant threat to safe driving and calls into question the belief that hands‐free voice‐controlled devices are the answer to the problem of driver distraction. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
140.
    
ABSTRACT

Cultural differences in autobiographical memory characteristics and function have often been presumed to be associated with different cultural beliefs related to the self. The current research aimed to investigate whether self-construal mediated the relationship between cultural group and the characteristics and functional use of autobiographical memory. Caucasian Australians (n?=?71) and Malay Malaysians (n?=?50) completed an online questionnaire that included the Self-Defining Memory task, the Thinking About Life Experiences Revised Questionnaire and the Self Construal Scale. As expected, the Australian group provided longer, more autonomously oriented, specific memories than the Malay group. However, contrary to our predictions, self-construal did not mediate the relationships between cultural group and memory characteristics. The Malay group reported more frequently using autobiographical memories for self-continuity than the Australian group. Finally, there was support for an indirect pathway between cultural group and use of autobiographical memories for self-continuity and social-bonding through self-construal (i.e. independent self relative to interdependent self). The findings highlight the importance of explicitly examining values assumed to be associated with autobiographical remembering, and relating these values to memory characteristics and function.  相似文献   
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