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231.
This study examined an activity restriction/pleasurable activities mismatch model for psychosocial and health-related outcomes. A total of 108 spousal caregivers of patients with Alzheimer's Disease (AD) were assessed for their experience of social and recreational activities over the past month as well as their perception of how restricted they were for engaging in social and recreational activities. Participants were divided into three groups based on their reported activities and activity restriction: HPLR = High Pleasant Events + Low Activity Restriction (i.e., reference group; N = 28); HPHR/LPLR = Either High Pleasant Events + High Activity Restriction or Low Pleasant Events + Low Activity Restriction (N = 43); LPHR = Low Pleasant Events + High Activity Restriction (N = 37). We hypothesized that participants reporting low pleasant events combined with high activity restriction (LPHR) would demonstrate greater disturbance relative to other two groups in multiple outcome domains, including: (a) greater mood disturbance, (b) greater use of negative coping factors, (c) reduced use of positive coping strategies, (d) reduced report of psychological resource factors (e.g., personal mastery, self-efficacy), and (e) increased report of subjective health difficulties (e.g., sleep disturbance). Results generally supported our hypotheses, suggesting that assessment of both constructs is important for best predicting quality of well-being in AD caregivers, and potentially for establishing maximal effect in behavior therapy for caregivers.  相似文献   
232.
Hein E  Moore CM 《Perception》2010,39(10):1330-1340
A central bar repeatedly presented in alternation with two flanking bars can lead to the disappearance of the central bar. Recently it has been suggested that this masking effect could be explained by object-mediated updating: the information from the central bar is integrated into the representation of the flankers, leading not only to the disappearance of the central bar as a separate object, but also to the perception of the flankers in apparent motion between their real position and the position of the central bar. This account suggests that the visibility of the central bar should depend on the same factors as those that influence the construction and maintenance of object representations. Therefore separation between central bar and flankers should not influence visibility as long as the time interval between them is adequate to make an interpretation of the scene in terms of one object moving from one location to the other possible location. We found that if the time interval between the central bar and the flankers is neither too short nor too long, the central bar becomes invisible even at large separations. These findings are inconsistent with traditional accounts of the cycling lateral masking displays in terms of local inhibitory mechanisms.  相似文献   
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234.
The current study examined how work support resources and working from home influenced forms of work-family conflict (WFC) in employees at a large corporation. Scales measuring employee’s general WFC, time-based WFC, and strain-based WFC were used to evaluate the extent to which employees experienced work-induced conflict at home. Two forms of working at home were assessed, days worked at home and extra hours worked at home, and five variables measured the extent of one’s support resources: work social support, organizational support, individual consideration from one’s manager, idealized influence from one’s manager and contingent reward from one’s manager. We predicted that days worked at home would be negatively related to the three forms of WFC, while the extra hours worked at home would be positively related. Moreover, we hypothesized that the five support variables would moderate the relationship between extra hours worked at home and the types of WFC. The data supported some of the predictions, and the implications of these findings are discussed.  相似文献   
235.
There are few studies on the development of anxiety and depression in orthopaedics and trauma (O&T) inpatients. We designed a cross-sectional study aimed at comparing the prevalence of depression and anxiety in 100 O&T inpatients and 100 clinical inpatients in the same hospital. O&T patients were divided into subgroups: trauma and non-trauma (arthroplasty, tumour, and infection sub grouping). We measured anxiety and depression by the Hospital Anxiety and Depression Scale and co-morbidities by the Charlson age-adjusted comorbidity index (CCI). For the trauma subgroup, AO/OTA fracture classification and Gustillo and Anderson grade of open fractures classification was applied. The prevalence of anxiety and depression was 35% and 28%, respectively for the clinical sample, and 44% and 33% for the O&T sample. Compared with the clinical sample, anxiety scores were higher in the O&T sample (p = .047), and in arthroplasty (p = .020) and trauma subgroups (p = .031). In the O&T sample, high CCI scores were associated with high anxiety scores (p = .033).  相似文献   
236.
What role do surface features (e.g., color) play in the establishment and maintenance of episodic representations of objects (object files)? Mitroff and Alvarez (2007) showed that stimuli that were linked by a continuous spatiotemporal history yielded object-specific preview benefits—a standard index of object files—whereas stimuli linked only by shared surface features did not. Here, it is shown that abruptly changing the features of an object that has been established on the basis of spatiotemporal history can disrupt object-specific preview benefits (Experiments 1 and 2). Moreover, under some conditions, feature match alone can give rise to the preview benefits (Experiment 3). These results indicate that surface features, as well as spatiotemporal factors, play an important role in establishing and maintaining episodic object representations.  相似文献   
237.
In this paper, we describe a digital scenario where we simulated the emergence of self-organized symbol-based communication among artificial creatures inhabiting a virtual world of unpredictable predatory events. In our experiment, creatures are autonomous agents that learn symbolic relations in an unsupervised manner, with no explicit feedback, and are able to engage in dynamical and autonomous communicative interactions with other creatures, even simultaneously. In order to synthesize a behavioral ecology and infer the minimum organizational constraints for the design of our creatures, we examined the well-studied case of communication in vervet monkeys. Our results show that the creatures, assuming the role of sign users and learners, behave collectively as a complex adaptive system, where self-organized communicative interactions play a major role in the emergence of symbol-based communication. We also strive in this paper for a careful use of the theoretical concepts involved, including the concepts of symbol and emergence, and we make use of a multi-level model for explaining the emergence of symbols in semiotic systems as a basis for the interpretation of inter-level relationships in the semiotic processes we are studying.  相似文献   
238.
The tendency to hear a tone sequence as 2 or more streams (segregated) builds up, but a sudden change in properties can reset the percept to 1 stream (integrated). This effect has not hitherto been explored using an objective measure of streaming. Stimuli comprised a 2.0-s fixed-frequency inducer followed by a 0.6-s test sequence of alternating pure tones (3 low [L]-high [H] cycles). Listeners compared intervals for which the test sequence was either isochronous or the H tones were slightly delayed. Resetting of segregation should make identifying the anisochronous interval easier. The HL frequency separation was varied (0-12 semitones), and properties of the inducer and test sequence were set to the same or different values. Inducer properties manipulated were frequency, number of onsets (several short bursts vs. one continuous tone), tone:silence ratio (short vs. extended bursts), level, and lateralization. All differences between the inducer and the L tones reduced temporal discrimination thresholds toward those for the no-inducer case, including properties shown previously not to affect segregation greatly. Overall, it is concluded that abrupt changes in a sequence cause resetting and improve subsequent temporal discrimination.  相似文献   
239.
This study examined effectiveness of Home‐Start, a program designed to support parents with young children. The aims were (a) to examine whether Home‐Start improved maternal well‐being and (b) to examine whether Home‐Start led to changes in the behavior of mothers or children. Self‐reported and observational data were collected in two waves, using data from 54 mothers and their children between 1.5 and 3.5 years of age who participated in this intervention program for 6 months. These data were compared to 51 comparison families who reported need for parenting support. The results showed a significant improvement in perceived parenting competence, but no effects on maternal depressive moods. Mixed results were found for parenting behavior: Parental consistency and observed sensitivity improved significantly in the Home‐Start group whereas no effects were found on the other parenting variables. Child behavioral problems seemed to diminish at the second measurement in both groups, and therefore these changes cannot be attributed to Home‐Start.  相似文献   
240.
Studies suggest motor deficit asymmetry may help predict the pattern of cognitive impairment in individuals with Parkinson disease (PD). We tested this hypothesis using a highly validated and sensitive spatial memory task, spatial delayed response (SDR), and clinical and neuroimaging measures of PD asymmetry. We predicted SDR performance would be more impaired by PD-related changes in the right side of the brain than in the left. PD (n = 35) and control (n = 28) participants performed the SDR task. PD participants either had worse motor deficits on the right (RPD) or left (LPD) side of the body. Some participants also had magnetic resonance imaging for measurement of their substantia nigra (SN) volumes. The LPD group performed worse on the SDR task than the RPD and control groups. Right SN volume accounted for a unique and significant portion of the variance in SDR error, with smaller volume predicting poorer performance. In conclusion, left motor dysfunction and smaller right SN volume are associated with poorer spatial memory.  相似文献   
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