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811.
Johnson AW Han S Blouin AM Saini J Worley PF During MJ Holland PC Baraban JM Reti IM 《Learning & memory (Cold Spring Harbor, N.Y.)》2010,17(12):620-626
Neuronal activity regulated pentraxin (Narp) is a secreted protein that regulates α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors (AMPAR) aggregation and synaptogenesis. Mapping of Narp-positive neurons in brain has revealed it is prominently expressed in several limbic system projection pathways. Consistent with this localization pattern, Narp knockout mice show deficits in using the current value of a reinforcer to guide behavior, a critical function of the limbic system. To help assess whether this behavioral deficit is due to impairment of synaptogenesis during development or in modulating synaptic signaling in the mature brain, we have used a dominant negative Narp viral construct which blocks trafficking of endogenous Narp to axons. Focal injection of this viral construct into the medial prefrontal cortex (mPFC) of adult mice, a region containing Narp-positive projection neurons, blocked reinforcer devaluation. Thus, these results indicate that Narp released from mPFC neurons plays a key role in mediating synaptic changes underlying instrumental reinforcer devaluation. 相似文献
812.
This preliminary study examined the factor structure of the Beliefs About Language Learning Inventory in two samples of about 750 college students of English as a foreign language in Taiwan. Results of confirmatory factor analysis lend partial support to Horwitz's theoretical five-factor belief model. Subsequent exploratory and confirmatory factor analyses of data show that a four-factor model represented by only 12 items performed better than other models both theoretically and empirically. This model consists of two dimensions already theorized in the inventory: Difficulty of Language Learning and Foreign Language Aptitude, and two newly interpreted dimensions, Importance of Spoken Language and Analytical Approaches to Language Learning. Although this four-factor model could be replicated in an independent sample, the factors are not reliable, suggesting the need to search for a more representative set of beliefs to tap specific aspects of language learning. 相似文献
813.
The current study examined the abilities of children (6 and 8 years of age) and adults to freely categorize and label dynamic bodily/facial expressions designed to portray happiness, pleasure, anger, irritation, and neutrality and controlled for their level of valence, arousal, intensity, and authenticity. Multidimensional scaling and cluster analyses showed that children (n = 52) and adults (n = 33) structured expressions in systematic and broadly similar ways. Between 6 and 8 years of age, there was a quantitative, but not a qualitative, improvement in labeling. When exposed to rich and dynamic emotional cues, children as young as 6 years can successfully perceive differences between close expressions (e.g., happiness, pleasure), and can categorize them with clear boundaries between them, with the exception of irritation, which had fuzzier borders. Children’s classifications were not reliant on lexical semantic abilities and were consistent with a model of emotion categories based on their degree of valence and arousal. 相似文献
814.
Majerus S Heiligenstein L Gautherot N Poncelet M Van der Linden M 《Journal of experimental child psychology》2009,103(1):66-86
This study investigated the role of auditory selective attention capacities as a possible mediator of the well-established association between verbal short-term memory (STM) and vocabulary development. A total of 47 6- and 7-year-olds were administered verbal immediate serial recall and auditory attention tasks. Both task types probed processing of item and serial order information because recent studies have shown this distinction to be critical when exploring relations between STM and lexical development. Multiple regression and variance partitioning analyses highlighted two variables as determinants of vocabulary development: (a) a serial order processing variable shared by STM order recall and a selective attention task for sequence information and (b) an attentional variable shared by selective attention measures targeting item or sequence information. The current study highlights the need for integrative STM models, accounting for conjoined influences of attentional capacities and serial order processing capacities on STM performance and the establishment of the lexical language network. 相似文献
815.
Can psychological distance affect how much perceivers form spontaneous trait inferences (STI) from others’ behaviors? On the basis of construal level theory (CLT) which posits that distant (vs. near) entities are represented more in terms of their abstract, global, and decontextualized features, we predicted that perceived distance would increase the tendency for perceivers to draw spontaneous trait inferences from behavioral information about actors. In two experiments, participants learned about people who were perceived as being distant or proximal to the self, and STI formation was subsequently assessed. We found that perceivers were more likely to form STIs about distant vs. near actors from the same behavioral information. These findings generalized across two distance dimensions: space and time. In addition, we found that priming individuals to adopt a high-level (vs. low-level) construal mindset also resulted in increased STI (Experiment 3). In sum, psychological distance facilitates STI formation, and this occurs via high-level construal of actors and their behaviors. 相似文献
816.
The "body image" is a putative mental representation of one's own body, including structural and geometric details, as well as the more familiar visual and affective aspects. Very little research has investigated how we learn the structure of our own body, with most researchers emphasising the canonical visual representation of the body when we look at ourselves in a mirror. Here, we used non-visual self-touch in healthy participants to investigate the possibility that primary sensorimotor experience may influence cognitive representations of one's own body structure. Participants used the fingers of one hand (the 'active' hand), to touch the fingers of the other (the 'passive' hand). A conflict between the experience of the active and passive hand was introduced by experimenter interleaving their fingers with the fingers of the participant's passive hand. This led to the active hand experiencing that it touched more fingers than the passive hand felt it was being touched by. The effects on representation of body structure were assessed using an implicit measure based on Kinsbourne and Warrington's 'in-between task'. We found an underestimation of the number of fingers in the central part of the hand specifically linked to the experience of self-touch. This pattern of results corresponds to the experience of the passive hand, but not the active hand. Nevertheless, comparable reorganisation of fingers within the hand representation was found for both active and passive hands. We show that primary sensorimotor experience can modify the representation of body structure. This modification is driven by the passive experience of being touched, rather than by the active experience of touching. We believe this is the first experimental study of effects of self-touch on the mental representation of the body. 相似文献
817.
MacAllister WS Bender HA Whitman L Welsh A Keller S Granader Y Sherman EM 《Child neuropsychology》2012,18(4):404-415
Children and adolescents with epilepsy are known to demonstrate executive function dysfunction, including working memory deficits and planning deficits. Accordingly, assessing specific executive function skills is important when evaluating these individuals. The present investigation examined the utility of two measures of executive functions-the Tower of London and the Behavioral Rating Inventory of Executive Functioning (BRIEF)-in a pediatric epilepsy sample. Ninety clinically referred children and adolescents with seizures were included. Both the Tower of London and BRIEF identified executive dysfunction in these individuals, but only the Tower of London variables showed significant relations with epilepsy severity variables such as age of epilepsy onset, seizure frequency, number of antiepileptic medications, etc. Further, the Tower of London and BRIEF variables were uncorrelated. Results indicate that objective measures of executive function deficits are more closely related to epilepsy severity but may not predict observable deficits, as reported by parents. Comprehensive evaluation of such deficits, therefore, should include both objective measures as well as subjective ratings from caregivers. 相似文献
818.
Embodied cognitive science appeals to the idea that cognition depends on the body as well as on the brain. This study looks at whether we are more likely to engage just the brain or enlist the body for complex cognitive functioning such as creative problem solving. Participants were presented with a puzzle based on De Bono's lateral thinking puzzles. The puzzle consisted of rotating and joining two-dimensional shapes to make a three-dimensional one. In one condition, participants were given the choice of either solving the puzzle mentally or through manipulation of the images on a computer screen. In another condition, the subjects had to solve the puzzle first mentally and then report which mode they would have preferred to solve the puzzle. Two more conditions were applied with slight variations. In all conditions, an overwhelming majority of participants chose to solve the puzzle by manipulation, even though there was not a significant increase on performance. It appeared that participants were making a conscious choice for the body to play a feedback-driven role in creative cognitive processing. This strong preference for manual manipulation over just mental representation, regardless of the impact on performance, would seem to suggest that it is our natural tendency to involve the body in complex cognitive functioning. This would support the theory that cognition may be more than just a neural process, and that it is a dynamic interplay between body, brain and world. The experiential feedback of the body moving through space and time may be an inherently important factor in creative cognition. 相似文献
819.
Virtual reality (VR) technology is increasingly used in spatial cognition research, as it offers high experimental control and interactivity in naturalistic multi-modal environments, something that is difficult to achieve in real-world settings. Even in the most sophisticated and costly VR systems, people do not necessarily perceive and behave as they would in the real world. This might be related to our inability to use embodied (and thus often highly automated and effective) spatial orientation processes in VR. While real-world locomotion affords automatic and obligatory spatial updating of our self-to-surrounding relationships, such that we easily remain oriented during simple perspective changes, the same is not necessarily true in VR. This can lead to striking systematic and qualitative errors such as failures to update rotations ("Nonturner" behavior). Here, we investigated whether rich naturalistic visual stimuli in immersive VR might be sufficient to compensate for the lack of physical motion. To this end, 24 participants performed point-to-origin tasks after visually simulated excursions along streets of varying curvature in a naturalistic virtual city. Most (21/24) participants properly updated simulated self-motions and showed only moderate regression toward mean pointing responses. 3/24 participants, however, exhibited striking "Nonturner" behavior in that they pointed as if they did not update the visually simulated turns and their heading had not changed. This suggests that our immersive naturalistic VR stimuli were an improvement over prior optic flow stimuli, but still insufficient in eliciting obligatory spatial updating that supported correct point-to-origin responses in all participants. 相似文献
820.
Autism spectrum disorder (ASD) symptoms are present in unaffected relatives and individuals from the general population. Results are inconclusive, however, on whether unaffected relatives have higher levels of quantitative autism traits (QAT) or not. This might be due to differences in research populations, because behavioral data and molecular genetic research suggest that the genetic etiology of ASD is different in multiplex and simplex families. We compared 117 unaffected siblings and 276 parents of at least one child with ASD with 280 children and 595 adults from the general population on the presence of QAT using the Social Responsiveness Scale (SRS). Mean SRS scores for siblings, control children, parents and control adults were 25.4, 26.6, 33.7 and 32.9. Fathers of children with ASD showed significantly higher levels of QAT than controls, but siblings and mothers did not. We could not detect a statistically significant difference in SRS scores between relatives from simplex and multiplex families. These results do not support the theory of differential (genetic) etiology in multiplex and simplex families and suggest that a carried genetic risk is generally not expressed phenotypically in most relatives, except in fathers. 相似文献