Associative learning performance is impaired in zebrafish (Danio rerio) by the NMDA-R antagonist MK-801

The zebrafish is gaining popularity in behavioral neuroscience perhaps because of a promise of efficient large scale mutagenesis and drug screens that could identify a substantial number of yet undiscovered molecular players involved in complex traits. Learning and memory are complex functions of the brain and the analysis of their mechanisms may benefit from such large scale zebrafish screens. One bottleneck in this research is the paucity of appropriate behavioral screening paradigms, which may be due to the relatively uncharacterized nature of the behavior of this species. Here we show that zebrafish exhibit good learning performance in a task adapted from the mammalian literature, a plus maze in which zebrafish are required to associate a neutral visual stimulus with the presence of conspecifics, the rewarding unconditioned stimulus. Furthermore, we show that MK-801, a non-competitive NMDA-R antagonist, impairs memory performance in this maze when administered right after training or just before recall but not when given before training at a dose that does not impair motor function, perception or motivation. These results suggest that the plus maze associative learning paradigm has face and construct validity and that zebrafish may become an appropriate and translationally relevant study species for the analysis of the mechanisms of vertebrate, including mammalian, learning and memory.     

初中生生活事件、心理韧性与学习倦怠的关系

目的:探讨初中生的学习倦怠、生活事件和心理韧性的关系。方法:从济宁市四所初级中学抽取465名初中生,以青少年生活事件量表、青少年心理韧性量表、中学生学习倦怠问卷为研究工具,对初中生进行测查。结果:初中生的学习倦怠水平随年级增长呈逐渐升高趋势;男生的学习倦怠水平显著高于女生;心理韧性作为中介变量,影响到生活事件与学习倦怠之间的关系,中介效应占总效应的比例为42.4%。结论:培养学生的心理韧性可以有助于降低他们的学习倦怠水平。     

Stimulus/response learning in masked congruency priming of faces: Evidence for covert mental classifications?

Reaction times for categorization of a probe face according to its sex or fame were contrasted as a function of whether the category of a preceding, sandwich-masked prime face was congruent or incongruent. Prime awareness was measured by the ability to later categorize the primes, and this was close to chance and typically uncorrelated with priming. When prime faces were never presented as visible probes within a test, priming was not reliable; when prime faces were also seen as probes, priming was only reliable if visible and masked presentation of faces were interleaved (not simply if primes had been visible in a previous session). In the latter case, priming was independent of experimentally induced face–response or face–category contingencies, ruling out any simple form of stimulus–response learning. We conclude that the reliable masked congruency priming reflects bindings between stimuli and multiple, abstract classifications that can be generated both overtly and covertly.     

Getting connected: Both associative and semantic links structure semantic memory for newly learned persons

The present study examined whether semantic memory for newly learned people is structured by visual co-occurrence, shared semantics, or both. Participants were trained with pairs of simultaneously presented (i.e., co-occurring) preexperimentally unfamiliar faces, which either did or did not share additionally provided semantic information (occupation, place of living, etc.). Semantic information could also be shared between faces that did not co-occur. A subsequent priming experiment revealed faster responses for both co-occurrence/no shared semantics and no co-occurrence/shared semantics conditions, than for an unrelated condition. Strikingly, priming was strongest in the co-occurrence/shared semantics condition, suggesting additive effects of these factors. Additional analysis of event-related brain potentials yielded priming in the N400 component only for combined effects of visual co-occurrence and shared semantics, with more positive amplitudes in this than in the unrelated condition. Overall, these findings suggest that both semantic relatedness and visual co-occurrence are important when novel information is integrated into person-related semantic memory.     

“I see what you mean”: Oral deaf individuals benefit from speaker's gesturing

Recent studies in the psychological literature reveal that cospeech gestures facilitate the construction of an articulated mental model of an oral discourse by hearing individuals. In particular, they facilitate correct recollections and discourse-based inferences at the expense of memory for discourse verbatim. Do gestures accompanying an oral discourse facilitate the construction of a discourse model also by oral deaf individuals trained to lip-read? The atypical cognitive functioning of oral deaf individuals leads to this prediction. Experiments 1 and 2, each conducted on 16 oral deaf individuals, used a recollection task and confirmed the prediction. Experiment 3, conducted on 36 oral deaf individuals, confirmed the prediction using a recognition task.     

Digit Span and Articulatory Suppression: A Cross-linguistic Comparison

Information Reduction, a performance-enhancing cognitive strategy which develops with practice, is thought to be consciously and abruptly adopted and then applied consistently. Previous investigations used an Alphabet Verification Task where one observation was that not everyone adopts the strategy, but reasons for this are unclear. We demonstrated Information Reduction in three other tasks, confirming that it is not task-specific. Post-testing questionnaires probed verbally expressible knowledge, to gauge conscious awareness of any strategy. Overall, results indicate considerable variation in Information Reduction usage: Some individuals discovered and used the strategy and could verbally express this, others chose not to use it and some appeared to use it without awareness of doing so. Results also indicate that Information Reduction is not consistently applied, suggesting it is less robust than has been proposed. Our results may be better explained by a theory of practice learning which incorporates both data-driven automaticity and top-down controlled processes.     

Continuities across continents: Assessing African American cultural themes among Black and Coloured South Africans

Much of the scholarship concerning African American culture is premised on the notion that it is a legacy of African origins but there has been essentially no attempt to document that relationship empirically. This paper briefly reviews existing evidence for cultural continuity in the Diaspora and then compares the responses of Black and Coloured South African and African Americans on measures of culture emic to African American populations. The observed patterns of psychometric performance, participants' responses, and the predictive utility of the measures employed were consistent with the thesis that despite inevitable variation, these three groups of the African Diaspora share similar orientations on the cultural themes assessed. This research hopes to initiate empirical work on the continuity thesis as it applies to connecting African American culture with a legacy of Africa and as related more broadly to the study of global Diasporas.     

An Evolutionary Analysis of Learned Attention

Humans and many other species selectively attend to stimuli or stimulus dimensions—but why should an animal constrain information input in this way? To investigate the adaptive functions of attention, we used a genetic algorithm to evolve simple connectionist networks that had to make categorization decisions in a variety of environmental structures. The results of these simulations show that while learned attention is not universally adaptive, its benefit is not restricted to the reduction of input complexity in order to keep it within an organism's processing capacity limitations. Instead, being able to shift attention provides adaptive benefit by allowing faster learning with fewer errors in a range of ecologically plausible environments.     

中学生学习主观幸福感的影响因素及其教育建议

学习主观幸福感对中学生整体生活的满意程度和心理健康有着重要的影响。本文分析了影响中学生学习主观幸福感的主要因素：学习体验、归因倾向、学习成绩、自我效能感及社会支持,并在此基础上提出了针对学校、教师及家庭的教育建议。