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941.
Spatial cognition is typically examined in non-human animals from the perspective of learning and memory. For this reason, spatial tasks are often constrained by the time necessary for training or the capacity of the animal’s short-term memory. A spatial task with limited learning and memory demands could allow for more efficient study of some aspects of spatial cognition. The traveling salesman problem (TSP), used to study human visuospatial problem solving, is a simple task with modifiable learning and memory requirements. In the current study, humans and rats were characterized in a navigational version of the TSP. Subjects visited each of 10 baited targets in any sequence from a set starting location. Unlike similar experiments, the roles of learning and memory were purposely minimized; all targets were perceptually available, no distracters were used, and each configuration was tested only once. The task yielded a variety of behavioral measures, including target revisits and omissions, route length, and frequency of transitions between each pair of targets. Both humans and rats consistently chose routes that were more efficient than chance, but less efficient than optimal, and generally less efficient than routes produced by the nearest-neighbor strategy. We conclude that the TSP is a useful and flexible task for the study of spatial cognition in human and non-human animals.  相似文献   
942.
The purpose of the current study is to create a comprehensive composite measure of parental influence based on previously developed measures to clarify the underlying dimensions of parental influence and to determine the degree to which parental influence relates to body image and dysfunctional weight concerns. Previously published literature was reviewed for measures of parental influence, and items from 22 measures were condensed and combined into a single questionnaire, which was completed by 367 female undergraduate psychology students. Two dimensions emerged from a principle components analysis: Direct Influence, which includes weight and eating related comments, and Modeling, which includes parental modeling of dieting and related behavior. Direct Influence and Modeling were significantly related to eating disturbance, such as drive for thinness and bulimic symptomatology. Overall, the results integrate the previous literature and clarify the underlying dimensions of parental influence. Further, this study provides directions for future research related to the development and maintenance of body image and eating disturbance.  相似文献   
943.
Depressed mood states affect subjective perceptions of time but it is not clear whether this is due to changes in the underlying timing mechanisms, such as the speed of the internal clock. In order to study depression effects on time perception, two experiments using time discrimination methods with short (<300?ms) and long (>1,000?ms) durations were conducted. Student participants who were categorized as mildly depressed by their scores on the Beck Depression Inventory were less able than controls to discriminate between two longer durations but were equally able to discriminate shorter intervals. The results suggest that mildly depressed or dysphoric moods do not affect pacemaker speed. It is more likely that depression affects the ability to maintain attention to elapsing duration.  相似文献   
944.
A major difference between humans and other animals is our capacity to maintain information in working memory (WM) while performing secondary tasks, which enables sustained, complex cognition. A common assumption is that the lateral prefrontal cortex (PFC) is critical for WM performance in the presence of distracters, but direct evidence is scarce. We assessed the relationship between fMRI activity and WM performance within subjects, with performance matched across distracter and no-distracter conditions. Activity in the ventrolateral PFC during WM encoding and maintenance positively predicted performance in both conditions, whereas activity in the presupplementary motor area (pre-SMA) predicted performance only under distraction. Other parts of the dorsolateral and ventrolateral PFCs predicted performance only in the no-distracter condition. These findings challenge a lateral-PFC-centered view of distracter resistance, and suggest that the lateral PFC supports a type of WM representation that is efficient for dealing with task-irrelevant input but is, nonetheless, easily disrupted by dual-task demands.  相似文献   
945.
This study addressed: (a) whether any changes in well-being over time could be attributed to participants’ aging or to economic or historical events; (b) whether predictors (e.g. age, religiosity, and financial status) were similarly associated with well-being in cohorts of college seniors assessed at different times; and (c) whether predictors of well-being were similar for the same cohort over a 25-year time span. Using three cohorts of emerging adults (1982, n?=?189; 2007, n?=?188; and 2010, n?=?79) and a subsample of the 1982 cohort followed across 25?years (n?=?83), the findings indicated that well-being declined over time, possibly due to historical influences rather than changes associated with aging. Well-being was similarly predicted by religiosity, relationship status, and financial status across cohorts. Longitudinal analyses indicated that earlier religiosity was inversely associated with later financial status and later financial status was associated with higher well-being.  相似文献   
946.
Personalized medicine continues to expand with the development and increasing use of genome-based testing. While these advances present new opportunities for diagnosis and risk assessment, they also present challenges to clinical delivery. Genetic counselors will play an important role in ushering in this new era of testing; however, it will warrant a shift from traditional genetic counseling to “genomic counseling.” This shift will be marked by a move from reactive genetic testing for diagnosis of primarily single-gene diseases to proactive genome-based testing for multiple complex diseases for the purpose of disease prevention. It will also require discussion of risk information for a number of diseases, some of which may have low relative risks or weak associations, and thus, may not substantially impact clinical care. Additionally, genomic counselors will expand their roles, particularly in the area of health promotion to reduce disease risk. This additional role will require a style of counseling that is more directive than traditional counseling and require greater knowledge about risk reducing behaviors and disease screening.  相似文献   
947.
Married adults are increasingly exposed to test results that indicate an increased genetic risk for adult-onset conditions. For example, a SERPINA1 mutation, associated with alpha-1 antitrypsin deficiency (AATD), predisposes affected individuals to diseases such as chronic obstructive pulmonary disease (COPD) and cancer, which are often detected in adulthood. Married adults are likely to discuss genetic test results with their spouses, and interpersonal research suggests that spouses’ communication patterns differ. Latent class analysis was used to identify subgroups of spousal communication patterns about AATD results from a sample of married adults in the Alpha-1 Research Registry (N?=?130). A five-class model was identified, and the subgroups were consistent with existing spousal-communication typologies. This study also showed that genetic beliefs (e.g., genetic stigma), emotions, and experiences (e.g., insurance difficulties) covaried with membership in particular subgroups. Understanding these differences can serve as the foundation for the creation of effective, targeted communications interventions to address the specific needs and conversational patterns of different kinds of couples.  相似文献   
948.
The primary aims of this study were to: (a) examine child perceptions of overprotection; and (b) explore how these perceptions relate to child health and adjustment. Children with a prior diagnosis of cancer (n = 205) and children without a history of serious illness (n = 76) reported on parental overprotective and caring behaviors. Children with cancer were recruited from one of four strata based on the elapsed time since their cancer diagnosis (1–6 months; 6–24 months; 2–5 years; >5 years) Children also reported on symptoms of depression, anxiety, and posttraumatic stress. Children with cancer did not differ from healthy children in their perceptions of parental care or overprotection. Child distress was more strongly related to perceptions of care and overprotection than child’s health status. Children with cancer do not report their parents approach to care and protection differently than children without a cancer history. These findings mirror prior research examining parental perceptions of overprotection and suggest that, despite the challenges of parenting a child with serious illness, parental protection is not significantly altered.  相似文献   
949.
Toddlers often display problem behavior during transitions. We rearranged naturally occurring events in a toddler classroom to promote more desirable classroom behavior during transitions to meals. In the intervention condition, teachers transitioned each child to meals only when that child was seated on a play mat (a requisite for engagement in teacher‐led play activities). In the reversal condition, teachers selected each child to transition when that child was by the barrier to the meal area (a practice commonly observed under natural conditions). The intervention increased the mean percentage of intervals when children were on the play mat and decreased the percentage of intervals when children were by the barrier. Individual child data show positive outcomes for five of six children. Results are discussed in terms of the positive effects of small manipulations to existing contingencies on classroom behavior as well as their potential influence on the adoptability of classroom interventions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
950.
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