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181.
Entorhinal neurons receive extensive intracortical projections, and form the primary input to the hippocampus via the perforant pathway. The glutamatergic cells of origin for the perforant pathway are distinguished by their expression of reelin, a glycoprotein involved in learning and synaptic plasticity. The functional significance of reelin signaling within the entorhinal cortex, however, remains unexplored. To determine whether interrupting entorhinal reelin signaling might have consequences for learning and memory, we administered recombinant receptor-associated protein (RAP) into the lateral entorhinal cortex (LEC) of young Long-Evans rats. RAP prevents reelin from binding to its receptors, and we verified the knockdown of reelin signaling by quantifying the phosphorylation state of reelin’s intracellular signaling target, disabled-1 (DAB1). Effective knockdown of reelin signaling was associated with impaired performance in the hippocampus-dependent version of the water maze. Moreover, inhibition of reelin signaling induced a localized loss of synaptic marker expression in the LEC. These observations support a role for entorhinal reelin signaling in spatial learning, and suggest that an intact reelin signaling pathway is essential for synaptic integrity in the adult entorhinal cortex.  相似文献   
182.
Happiness is a key ingredient of well-being. It is thus reasonable to expect that valuing happiness will have beneficial outcomes. We argue that this may not always be the case. Instead, valuing happiness could be self-defeating, because the more people value happiness, the more likely they will feel disappointed. This should apply particularly in positive situations, in which people have every reason to be happy. Two studies support this hypothesis. In Study 1, female participants who valued happiness more (vs. less) reported lower happiness when under conditions of low, but not high, life stress. In Study 2, compared to a control group, female participants who were experimentally induced to value happiness reacted less positively to a happy, but not a sad, emotion induction. This effect was mediated by participants' disappointment at their own feelings. Paradoxically, therefore, valuing happiness may lead people to be less happy just when happiness is within reach.  相似文献   
183.
Differences in the presentation of clinical features of body dysmorphic disorder (BDD) across ethnic groups have received little investigation. The current study assessed BDD symptoms in an ethnically diverse sample of adults (n=401) using an online survey. Participants completed self-report measures assessing BDD symptoms, body parts of concern and BDD behaviors. Compared to Caucasian participants, no significant differences were found in body parts or behaviors reported by Latino or African American participants. Significant group differences did emerge between Asian and Caucasian participants. Specifically, Asians reported more concern with straight hair and dark skin and fewer body shape concerns than Caucasians. Asians also endorsed lower rates of grooming, touching body parts, and camouflaging and higher rates of exercise compared to Caucasians. Although most clinical features of BDD appear similar across ethnic groups, results showed some differences in body parts and behaviors between Caucasians and Asian Americans with BDD symptoms.  相似文献   
184.
An experiment was conducted to determine the coordinate system used in the development of movement codes during observation and utilized on later physical practice performance of a simple spatial-temporal movement sequence. The task was to reproduce a 1.3-s spatial-temporal pattern of elbow flexions and extensions. An intermanual transfer paradigm with a retention test and two transfer tests was used: a mirror transfer test where the same pattern of muscle activation and limb joint angles was required and a nonmirror transfer test where the visual-spatial pattern of the sequence was reinstated on the transfer test. The results indicated a strong advantage for participants in the physical practice condition when transferred to the mirror condition in which the motor coordinates (e.g., pattern of muscle activation and joint angles) were reinstated relative to transfer performance when the visual-spatial coordinates were reinstated (visual and spatial location of the target waveform). The observation group, however, demonstrated an advantage when the visual-spatial coordinates were reinstated. These results demonstrate that codes based in motor coordinates can be developed relatively quickly for simple rapid movement sequences when participants are provided physical practice, but observational practice limits the system to the development of codes based in visual-spatial coordinates. Performances of control participants, who were not permitted to practise or observe the task, were quite poor on all tests.  相似文献   
185.
To explore potential response shift effects with different quality of life (QoL) instruments in cardiac patients undergoing coronary intervention. Study Design and Setting: Recalibration was assessed with the disease specific health-related quality of life (HRQL) instrument MacNew in combination with a then-test approach. Reconceptualisation and reprioritisation were assessed with the individualised QoL instrument SEIQoL-DW. Significant treatment effects were seen on the MacNew (global Δ: 0.6 ± 1.1, p = 0.004) but not on the SEIQoL-DW (Δ: 3.3 ± 16, p = 0.37) 6 months after coronary intervention. No recalibration effect was found on the MacNew then-test, while with the SEIQOL-DW potential response shift effects of reconceptualisation and reprioritisation were seen. For the first time response shift effects were explored in cardiac patients undergoing coronary intervention. This study confirmed that there is a clinically significant improvement in disease specific HRQL over time following successful coronary interventions. However, no treatment effect was seen for individualised QoL with the SEIQoL-DW. This might be due to reconceptualisation and reprioritisation response effects. Future studies need to focus on exploring response shift effects, and the interrelationship between its different components, captured by different patient reported outcome instruments in larger patient groups undergoing coronary interventions.  相似文献   
186.
This study describes an unexpected behavioral process that influenced behavior during the teaching of concepts to a 4-year-old girl. The efficacy of and preference for three strategies that varied in teacher directedness were assessed in a multielement design and concurrent-chains arrangement, respectively. The strategy that involved the most teacher direction was most efficacious and preferred. In addition, embedded teacher prompts, common in child-led teaching procedures, functioned as a punisher for the child's toy play. Implications for designing effective and preferred teaching conditions are discussed.  相似文献   
187.
We observed 11 undergraduates in an experiment designed to simulate infant caregiving. In negative reinforcement conditions experienced by all participants, a targeted caregiving response (e.g., rocking a baby doll) produced escape from, and avoidance of, a recorded infant cry. Nine participants' caregiving was shown to be controlled by this negative reinforcement contingency. Nine participants experienced an extinction condition that consisted of an inescapable cry, and the previously reinforced caregiving responses of 2 of these participants were resistant to extinction. For both of these participants, the previously reinforced response was eliminated when an alternative form of caregiving was reinforced. These results highlight the role of negative reinforcement in infant caregiving and suggest the need for additional research on the effects of crying on caregivers as well as the development of effective strategies for minimizing infant crying.  相似文献   
188.
Research shows a strong link between adult attachment and mental and physical health, but little is known about the mechanisms that underlie these relationships. The present study examined self-compassion and mattering, two constructs from positive psychology literature, as potential mediators. Using survey data from a sample of 208 college students, relationships among attachment, self-compassion, mattering, and functional health were explored. Correlational analyses indicated that attachment anxiety and avoidance were strongly related to the mental health component of functional health. Mediation analyses indicated that mattering and self-compassion mediated the relationships between attachment orientation (i.e., levels of avoidance and anxiety) and mental health. These findings suggest that individuals' abilities to be kind toward themselves and their sense of belonging and being important to others are pathways through which attachment orientation relates to mental health.  相似文献   
189.
Over the past decade, structured programming for children and youth during the non-school hours has expanded exponentially. A confluence of recent research studies and program evaluations backs the publicly perceived notion that after-school programs can positively influence important developmental and learning outcomes. The rapid expansion of the field and the potential of programs to contribute to child and youth development have made defining what high quality programs look like and learning how to improve program quality key challenges facing the field. This paper describes what is known about the relation between youth program quality and youth developmental outcomes, summarizes different quality assessment tools being used in the field, and discusses how such tools are being used to drive systemic quality improvement efforts.  相似文献   
190.
Although proposed by bioecological models, there has been minimal empirical examination of whether children's individual differences moderate neighborhood effects on development. We used an urban community sample (8-12 years, N = 316) to examine interactions among neighborhood characteristics (problems and social organization) and children's temperament (fear, irritability and impulsivity) in predicting psychosocial adjustment. The main effects of neighborhood and temperament on outcomes were consistent with previous research. Findings show that development is challenging in disadvantaged neighborhoods whatever one's temperament, however, some effects of neighborhood were conditioned by temperament, particularly children's fear and irritability. Neighborhood problems were more strongly related to lower social competence for fearful and for less irritable children. Neighborhood problems were more strongly related to higher internalizing problems for low-fear children. Neighborhood social organization was more strongly related to greater social competence for low-fear children. Findings are discussed in relation to "diathesis-stress" and "differential responsiveness" models of temperament.  相似文献   
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