Hippocampal c-fos is necessary for long-term memory of a socially transmitted food preference

The present article examined the requirement of hippocampal c-Fos for learning a socially transmitted food preference (STFP). We reported previously that expression of the c-Fos protein is increased in the dorsal and ventral hippocampus of rats trained on the STFP (Countryman, Orlowski, Brightwell, Oskowitz, & Colombo, 2005). Pretraining intrahippocampal antisense to the immediate early gene c-fos was administered to adult male Long-Evans rats to determine if c-fos expression is necessary for either short- or long-term memory for STFP. Guide cannulae were implanted bilaterally into the dorsal hippocampus. Antisense oligodeoxynucleotides (ODNs) were administered unilaterally either 6.5, 8.5, 10.5, or 12.5 h prior to STFP training while either sense ODNs or saline were infused into the opposite hemisphere. Immunocytochemistry was performed, and cells showing c-Fos immunoreactivity (ir) were counted from the antisense-treated hemisphere and compared to cell counts from the control hemisphere. The results indicated significant suppression of learning-induced c-Fos protein at the 8.5 and 10.5 infusion-train intervals. Additional rats were implanted with cannulae into the dorsal and ventral hippocampus, and antisense ODNs, sense ODNs, or saline were administered bilaterally 8.5h prior to training. Rats were tested immediately and 14 days after training. Rats in all groups showed a significant preference for the demonstrated food at the short-term memory test. At the long-term memory test, however, rats infused with c-fos antisense showed no preference for the demonstrated food whereas rats infused with either sense or saline maintained their preference. The present findings suggest that c-fos is necessary for consolidation of non-spatial hippocampal-dependent memory.     

Acquiring new spatial intuitions: learning to reason about rotations

There are certain simple rotations of objects that most people cannot reason about accurately. Reliable gaps in the understanding of a fundamental physical domain raise the question of how learning to reason in that domain might proceed. Using virtual reality techniques, this project investigated the nature of learning to reason across the domain of simple rotations. Learning consisted of the acquisition of spatial intuitions: there was encoding of useful spatiotemporal information in specific problem types and a gradual accumulation of this understanding across the domain. This pattern of learning through the accumulation of intuitions is especially interesting for rotational motion, in which an elegant domain-wide kinematics is available to support insightful learning. Individual ability to reason about rotations correlated highly with mastery motivation, skill in fluid reasoning, and skill in reasoning about spatial transformations. Thus, general cognitive advantages aided the understanding of individual rotations without guaranteeing immediate generalization across the domain.     

Speech segmentation by statistical learning depends on attention

We addressed the hypothesis that word segmentation based on statistical regularities occurs without the need of attention. Participants were presented with a stream of artificial speech in which the only cue to extract the words was the presence of statistical regularities between syllables. Half of the participants were asked to passively listen to the speech stream, while the other half were asked to perform a concurrent task. In Experiment 1, the concurrent task was performed on a separate auditory stream (noises), in Experiment 2 it was performed on a visual stream (pictures), and in Experiment 3 it was performed on pitch changes in the speech stream itself. Invariably, passive listening to the speech stream led to successful word extraction (as measured by a recognition test presented after the exposure phase), whereas diverted attention led to a dramatic impairment in word segmentation performance. These findings demonstrate that when attentional resources are depleted, word segmentation based on statistical regularities is seriously compromised.     

Acetylcholine actions in the dorsomedial striatum support the flexible shifting of response patterns

There is accumulating evidence that the dorsomedial striatum plays a significant role in the learning of a new response pattern and the inhibiting of old response patterns when conditions demand a shift in strategies. This paper proposes that activity of cholinergic neurons in the dorsomedial striatum is critical for enabling behavioral flexibility when there is a change in task contingencies. Recent experimental findings are provided supporting this idea. Measuring acetylcholine efflux from the dorsomedial striatum during the acquisition and reversal learning of a spatial discrimination shows that acetylcholine efflux selectively increases during reversal learning as a rat begins to learn a newly reinforced spatial location, but returns to near basal levels when a rat reliably executes the new choice pattern. Experimental findings are also described indicating that the blockade of muscarinic cholinergic receptors in the dorsomedial striatum does not impair acquisition of an egocentric response discrimination, but impairs reversal learning of an egocentric response discrimination. Based on these results, increased cholinergic activity at muscarinic receptors is part of a neurochemical process in the dorsomedial striatum that allows inhibition of a previously relevant response pattern while learning a new response pattern. In situations that demand behavioral flexibility, muscarinic cholinergic activity in the dorsomedial striatum may directly influence corticostriatal plasticity to produce changes in response patterns.     

The developmental course of processing speed in children with and without learning disabilities

This study contrasted the development of processing speed in children with and without learning disabilities. We examined whether the same global mechanism presumed to be responsible for the normal developmental improvement in processing speed might also be associated with the processing speed deficiencies observed in children with learning impairments. One hundred and twenty-two children with learning disabilities in reading and/or math and 206 non-disabled community controls participated. There were no differences in relation of age to the development of processing speed for children with and without learning disabilities. We interpreted these results as suggesting that the underlying etiologies for the normal developmental change in processing speed and for the relative deficiencies in processing speed seen among children with learning disabilities were different.     

The Dimensionality of Honey and Mumford’s Learning Styles Questionnaire

The Learning Style Questionnaire (LSQ) developed by Honey and Mumford (1986) is one of several measures of individual learning style. Despite its popularity in the UK there is little published evidence for construct validity. This survey of 329 British managers used cluster and factor analysis to assess the validity of the LSQ. Cluster analysis revealed learning style profiles dominated by Reflector/Theorist traits. The factor structure of the LSQ does not cleanly reflect the four-stage Learning Cycle relied upon for a theoretical foundation. The observed structure is more indicative of a three-stage learning cycle of Action, Reflection and Planning.     

Developmental changes in free recall: The interaction of task structure and age

Free-recall learning and organization were measured for 3rd, 7th, and 11th graders under conditions which varied the type and amount of task structure. Task structure for the input or list-presentation phase was manipulated by using a random, constant, or alphabetic item sequence across trials. Task structure for the output or recall phase was manipulated by providing standard instructions or instructions which suggested the possible use of an alphabetic ordering scheme. Recall performance and organization showed an interaction between age and both manipulations of task structure. The 3rd graders required the maximal amount of task structure (alphabetic order with alphabetic instructions) to demonstrate recall facilitation relative to the completely unstructured control condition. The 7th graders showed recall facilitation for intermediate and high levels of task structure, and the 11th graders showed recall facilitation for low, intermediate, and high levels of task structure. The results are related to current hypotheses about developmental changes in recall performance and their relationship to changes in the systematic use of organizational strategies.     

如何导引"儒门道脉同归佛海"?——蕅益智旭对《论语》的解释

该文分析十七世纪蕅益智旭(1599-1677)对《论语》的思想世界的解释。该文首先指出,智旭以无限生命、死生一致的观点作为核心,重构孔门的生死观,再以心学之立场重新解释孔子思想中的“学”、“道”与“天命”三个重要概念。智旭将“学”解释为“心”之觉醒,将“道”理解为“空生大觉”之道,将“知天命”解释为对“不生不灭之理”与“虚妄生灭之原”的通透。凡此种种新诠,在东亚《论语》诠释史上,均有其特殊性,一方面展现王阳明以后以“心”学解释经典的“自由的”学风,另一方面则显示明末三教合一之思想趋向。     

Perfectionism, intrinsic vs extrinsic motivation, and motivated strategies for learning: a multidimensional analysis of university students

We investigated the interrelations between dimensions of perfectionism and measures of academic motivation and learning strategies in university students. When partial correlation analysis was employed to examine the unique relation between specific perfectionism subscales and motivation/learning scales, self-oriented perfectionism was significantly related to students’ motivation and learning strategies in positive, adaptive ways whereas socially prescribed perfectionism was related in negative, maladaptive ways. Self-oriented perfectionists were motivated primarily by extrinsic compensation for their academic work whereas socially prescribed perfectionists were more motivated by recognition from others. Self-oriented perfectionism was significantly positively associated with self-efficacy for learning and performance, adaptive metacognitive and cognitive learning strategies, and effective resource management. Socially prescribed perfectionism was associated negatively with these measures. In addition, self-oriented perfectionism was associated positively with intrinsic goal orientation for a specific course, task value, and critical thinking whereas socially prescribed perfectionism was associated with test anxiety and a decreased likelihood of help-seeking. The theoretical importance of these findings and the implications for devising strategic counseling interventions are discussed.     

Is a Worried Citizen a Good Citizen? Emotions,Political Information Seeking,and Learning via the Internet

In this study we explore the mediating role of emotions in the process of becoming a politically informed citizen. Contrary to previous studies, we expect that anger and anxiety will have much different effects on this process. We suspect the role of anxiety is somewhat unique even among negative emotions as mediator of the causal effect of political threats on information seeking and learning. In addition, we speculate that anxiety should improve the quality of information seeking, not just its quantity. In one experiment, we induce emotions directly and find that while anger, enthusiasm, and anxiety can lead people to claim they will pay attention to the campaign, anger actually depresses total information seeking. In a second experiment, we examine the impact of realistic political threats and find that exposure triggers several emotions but that only anxiety boosts information seeking and learning.