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81.
Pigs are a valuable animal model for studying neurodevelopment in humans due to similarities in brain structure and growth. The development and validation of behavioral tests to assess learning and memory in neonatal piglets are needed. The present study evaluated the capability of 2-week old piglets to acquire a novel place and direction learning spatial T-maze task. Validity of the task was assessed by the administration of scopolamine, an anti-cholinergic drug that acts on the hippocampus and other related structures, to impair spatial memory. During acquisition, piglets were trained to locate a milk reward in a constant place in space, as well as direction (east or west), in a plus-shaped maze using extra-maze visual cues. Following acquisition, reward location was reversed and piglets were re-tested to assess learning and working memory. The performance of control piglets in the maze improved over time (P < 0.0001), reaching performance criterion (80 % correct) on day 5 of acquisition. Correct choices decreased in the reversal phase (P < 0.0001), but improved over time. In a separate study, piglets were injected daily with either phosphate-buffered saline (PBS; control) or scopolamine prior to testing. Piglets administered scopolamine showed impaired performance in the maze compared to controls (P = 0.03), failing to reach performance criterion after 6 days of acquisition testing. Collectively, these data demonstrate that neonatal piglets can be tested in a spatial T-maze task to assess hippocampal-dependent learning and memory.  相似文献   
82.
It has been suggested that downward pointing triangles convey negative valence, perhaps because they mimic an underlying primitive feature present in negative facial expressions (Larson, Aronoff, and Stearns, 2007). Here, we test this proposition using a flanker interference paradigm in which participants indicated the valence of a central face target, presented between two adjacent distracters. Experiment 1 showed that, compared with face flankers, downward pointing triangles had little influence on responses to face targets. However, in Experiment 2, when attentional competition was increased between target and flankers, downward pointing triangles slowed responses to positively valenced face targets, and speeded them to negatively valenced targets, consistent with valence-based flanker compatibility effects. These findings provide converging evidence that simple geometric shapes may convey emotional valence.  相似文献   
83.
Participants were presented with sentences mentioning an entity with a typical location in the upper or lower vertical space (e.g., roof vs. root). Sentences supported or reversed the typical location of the target entity. Sensibility judgments requiring upwards or downwards responses were faster when the response matched rather than mismatched the target entity's typical location. This compatibility effect was independent of whether the sentence context supported or reversed the target entity's typical location. The results, therefore, provide clear evidence for word-based but no evidence for sentence-based simulation processes.  相似文献   
84.
Behavioral activation that is associated with incentive-reward motivation increases in adolescence relative to childhood and adulthood. This quadratic developmental pattern is generally supported by behavioral and experimental neuroscience findings. It is suggested that a focus on changes in dopamine neurotransmission is informative in understanding the mechanism for this adolescent increase in reward-related behavioral activation and subsequent decline into adulthood. Evidence is presented to indicate that incentive-reward motivation is modulated by mesoaccumbens dopamine, and that it increases in adolescence before declining into adulthood because of normative developmental changes at the molecular level. Potential mechanisms of variation in functional mesoaccumbens dopamine transmission are discussed with a focus on the interplay between tonic and phasic modes of dopamine transmission in modulating both general incentive-motivational biases and the efficacy of reward learning during exposure to novel reward experiences. Interactions between individual difference factors and these age-related trends are discussed.  相似文献   
85.
The exhibition of actions that are causally unnecessary to the outcomes with which they are associated is a core feature of human cultural behavior. To enter into the world(s) of their cultural in-group, children must learn to assimilate such unnecessary actions into their own behavioral repertoire. Past research has established the habitual tendency of children to adopt the redundant actions of adults demonstrated directly to them. Here we document how young children will do so even when such actions are modeled to a third person regardless of whether children are presented with the test apparatus by the demonstrating, and assumedly expert, adult or by the observing, and assumedly naive, adult (Experiment 1), whether or not children had opportunity to discover how the apparatus works prior to modeling (Experiment 1), and whether or not children's attention was drawn to the demonstration while they were otherwise occupied (Experiment 2). These results emphasize human children's readiness to acquire behavior that is in keeping with what others do, regardless of the apparent efficiency of the actions employed, and in so doing to participate in cultural learning.  相似文献   
86.
Feedback on task performance is often phrased in subjective language (e.g., “not bad!”), but how do recipients understand or translate that feedback into a clear, objective, performance metric? We suggest that when feedback is provided in a stereotype-relevant domain, translation is made with reference to stereotyped expectations for one's group. In Study 1, women and men were exposed to negative subjective feedback about their performance on a leadership task; in Study 2, Black and White participants were provided subjective negative feedback, or no feedback, on an academic writing task. Women relative to men, and Black students relative to White students, translated their feedback to indicate objectively worse performance. Furthermore, this translation mediated a drop in the importance placed on the domain among women and Blacks. This research extends the literature on gender- and race-based reactions to feedback by noting the importance of the immediate interpretation of the feedback received.  相似文献   
87.
ADHD is associated with academic underachievement, but it remains unclear what mechanism accounts for this association. Semantic language is an underexplored mechanism that provides a developmental explanation for this association. The present study will examine whether semantic language deficits explain the association between ADHD and reading and mathematics underachievement, taking into account alternative explanations for associations, including verbal working memory (WM) impairments, as well as specificity of effects to inattentive and hyperactive-impulsive ADHD symptom domains. Participants in this cross-sectional study were 546 children (54?% male) ages six to twelve (M?=?9.77, SD?=?1.49). ADHD symptoms were measured via maternal and teacher report during structured interviews and on standardized rating forms. Children completed standardized semantic language, verbal WM, and academic testing. Semantic language fully mediated the ADHD-reading achievement association and partially mediated the ADHD-mathematics achievement association. Verbal WM also partially mediated the ADHD-mathematics association but did not mediate the ADHD-reading achievement association. Results generalized across inattentive and hyperactive-impulsive ADHD symptom domains. Semantic language explained the association between ADHD and reading underachievement and partially explained the association between ADHD and mathematics underachievement. Together, language impairment and WM fully explained the association between ADHD and reading underachievement, in line with developmental models suggesting that language and WM conjointly influence the development of attention and subsequent academic achievement. This work has implication for the development of tailored interventions for academic underachievement in children with ADHD.  相似文献   
88.
This study examined the relations of dysregulated negative emotional reactivity, emotional distress, and chronic peer victimization in childhood. A model was proposed whereby dysregulated reactivity was directly and indirectly related to concurrent peer victimization through victimization‐related emotional distress. The model further proposed that dysregulated reactivity directly incrementally predicted longitudinal peer victimization above and beyond the effect of concurrent victimization. Two hundred thirteen 9‐ to 13‐year‐old children and their parents completed measures of dysregulated reactivity and victimization experiences at baseline and 6‐month follow‐up. Children also related narratives of personal victimization experiences at baseline that were coded to assess victimization‐related emotional distress. Model testing strongly supported the direct association of dysregulated reactivity with concurrent victimization and incremental predictive effects of dysregulated reactivity on peer victimization over time. Model testing also provided support for an indirect effect of dysregulated reactivity on concurrent peer victimization through victimization‐related emotional distress. This study demonstrated the powerful role that dysregulated negative emotional reactivity plays in the development of chronic peer victimization over time. Aggr. Behav. 38:414‐427, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
89.
The study evaluated trait associations with common Disruptive Behavior Disorders (DBD), Oppositional Defiant Disorder (ODD) and Attention-Deficit/Hyperactivity Disorder (ADHD), during an understudied developmental period: preschool. Participants were 109 children ages 3–6 and their families. DBD symptoms were available via parent and teacher/caregiver report on the Disruptive Behavior Rating Scale. Traits were measured using observational coding paradigms, and parent and examiner report on the Child Behavior Questionnaire and the California Q-Sort. The DBD groups exhibited significantly higher negative affect, higher surgency, and lower effortful control. Negative affect was associated with most DBD symptom domains; surgency and reactive control were associated with hyperactivity-impulsivity; and effortful control was associated with ADHD and inattention. Interactive effects between effortful control and negative affect and curvilinear associations of reactive control with DBD symptoms were evident. Temperament trait associations with DBD during preschool are similar to those seen during middle childhood. Extreme levels of temperament traits are associated with DBD as early as preschool.  相似文献   
90.
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