Search

Visual search requires the maintenance of a search template in visual working memory in order to guide attention towards the target. This raises the question whether a search template is essentially the same as a visual working memory representation used in tasks that do not require attentional guidance, or whether it is a qualitatively different representation. Two experiments tested this by comparing electrophysiological markers of visual working memory maintenance between simple recognition and search tasks. For both experiments, responses were less rapid and less accurate in search task than in simple recognition. Nevertheless, the contralateral delay activity (CDA), an index of quantity and quality of visual working memory representations, was equal across tasks. On the other hand, the late positive complex (LPC), which is sensitive to the effort invested in visual working memory maintenance, was greater for the search task than the recognition task. Additionally, when the same target cue was repeated across trials (Experiment 2), the amplitude of visual working memory markers (both CDA and LPC) decreased, demonstrating learning of the target at an equal rate for both tasks. Our results suggest that a search template is qualitatively the same as a representation used for simple recognition, but greater effort is invested in its maintenance. [ABSTRACT FROM AUTHOR]

Visual search is speeded when the target is repeated from trial to trial compared to when it changes, suggesting that selective attention learns from previous events. Such intertrial effects are stronger when there is more competition for selection, for example in ambiguous displays where the target is accompanied by a salient distractor. Here we investigate whether this is because the competition strengthens the learning itself, or because it allows for a learned representation to exert a greater effect. The results point to the latter. Observers looked for a colour-defined target that could repeat or change from trial to trial. A salient distractor could be present on the current trial, the previous trial, both, or neither. Intertrial effects were greater when a distractor was present on the current trial, suggesting that a primed target representation is more beneficial under conditions of competition. In contrast, distractor presence on the previous trial had no effects whatsoever, indicating that the learning process itself is not affected by competition. This suggests that the source of the learning resides at postselection stages, whereas the effects may occur at the perceptual level. [ABSTRACT FROM AUTHOR]

The hippocampal region, a group of brain structures important for learning and memory, has been the focus of a large number of computational models. These tend to fall into two groups: (1) models of the role of the hippocampal region in incremental learning, which focus on the development of new representations that are sensitive to stimulus regularities and environmental context; (2) models that focus on the role of the hippocampal region in the rapid storage and retrieval of episodic memories. Rather than being in conflict, it is becoming apparent that both approaches are partially correct and might reflect the different functions of substructures of the hippocampal region. Future computational models will help to elaborate how these different substructures interact. [Copyright &y& Elsevier]

We compared judgments of learning (JOLs) that were made either (a) after 1 study trial, (b) 2 study trials, or (c) in-between the 1st and 2nd study trials. In regard to the absolute accuracy of JOLs at predicting subsequent recall, we replicated previous findings of an underconfidence-with-practice effect for immediate JOLs and report for the first time a new finding of an underconfidence-with-practice effect for delayed JOLs (i.e., delayed JOLs after one trial overestimated the likelihood of subsequent recall, whereas delayed JOLs after two trials underestimated that likelihood). Also, although delayed JOLs always had a greater relative accuracy than did immediate JOLs, the relative accuracy of immediate and delayed JOLs was approximately the same after 1 versus 2 study trials. These results demonstrate that additional study trials affect the absolute accuracy of all JOLs but not the relative accuracy of any JOLs. Thus an increase in the number of study trials produced an increasing bias to be underconfident about the subsequent likelihood of recall but did not affect people’s ordering of which items had been more (versus less) well-learned. [Copyright &y& Elsevier]

Although many of our perceptual biases stem from long-term, repeated exposure, current theories of visual search assume a central role for visual working memory (VWM) in guiding attention to target information. Crucially, whether a VWM representation guides attention depends on the relative priority that the memory has within VWM. Here, in a combined visual search/VWM task, we used attentional guidance by irrelevant memories to measure how long a target representation remains prioritized in VWM when observers repeatedly search for the same target. Irrelevant memories started guiding attention already when the target was repeated once, indicating that the target representation rapidly lost priority within VWM as it moved to long-term memory. By showing that training can lead to interference from irrelevant memories, the findings resolve a long-standing paradox on why VWM appears central to, yet at the same time not sufficient nor necessary for attentional guidance. [ABSTRACT FROM AUTHOR]

Prominent theories of attention claim that visual search is guided through attentional templates stored in working memory. Recently, the contralateral delay activity (CDA), an electrophysiological index of working memory storage, has been found to rapidly decrease when participants repeatedly search for the same target, suggesting that, with learning, the template moves out of working memory. However, this has only been investigated with pop-out search for distinct targets, for which a strong attentional template may not be necessary. More effortful search tasks might rely more on an active attentional template in working memory, leading to a slower handoff to long-term memory and thus a slower decline of the CDA. Using ERPs, we compared the rate of learning of attentional templates in pop-out and effortful search tasks. In two experiments, the rate of decrease in the CDA was the same for both search tasks. Similar results were found for a second component indexing working memory effort, the late positive complex. However, the late positive complex was also sensitive to anticipated search difficulty, as was expressed in a greater amplitude before the harder search task. We conclude that the amount of working memory effort invested in maintaining an attentional template, but not the rate of learning, depends on search difficulty. [ABSTRACT FROM AUTHOR]

Background: Active learning relies on students' engagement with teachers, study materials and/or each other. Although medical education has adopted active learning as a core component of medical training, teachers have difficulties recognising when and why their students engage or disengage and how to teach in ways that optimise engagement. With a better understanding of the dynamics of student engagement in small‐group active learning settings, teachers could be facilitated in effectively engaging their students. Methods: We conducted a video‐stimulated recall study to explore medical students' engagement during small‐group learning activities. We recorded one teaching session of two different groups and selected critical moments of apparent (dis)engagement. These moments served as prompts for the 15 individual semi‐structured interviews we held. Interview data were analysed using Template Analysis style of thematic analysis. To guide the analysis, we used a framework that describes student engagement as a dynamic and multidimensional concept, consisting of behavioural, cognitive and emotional components. Results: The analysis uncovered three main findings: (1) In‐class student engagement followed a spiral‐like pattern. Once students were engaged or disengaged on one dimension, other dimensions were likely to follow suit. (2) Students' willingness to engage in class was decided before class, depending on their perception of a number of personal, social and educational antecedents of engagement. (3) Distinguishing engagement from disengagement appeared to be difficult for teachers, because the intention behind student behaviour was not always identifiable. Discussion: This study adds to the literature by illuminating the dynamic process of student engagement and explaining the difficulty of recognising and influencing this process in practice. Based on the importance of discerning the intentions behind student behaviour, we advise teachers to use their observations of student (dis)engagement to initiate interaction with students with open and inviting prompts. This can help teachers to (re‐)engage students in their classrooms. This study illuminates the dynamic process of student engagement in small‐group active learning settings and explains the difficulty teachers have recognizing and influencing engagement in practice. [ABSTRACT FROM AUTHOR]

The question of how learners' motivation influences their academic achievement and vice versa has been the subject of intensive research due to its theoretical relevance and important implications for the field of education. Here, we present our understanding of how influential theories of academic motivation have conceptualized reciprocal interactions between motivation and achievement and the kinds of evidence that support this reciprocity. While the reciprocal nature of the relationship between motivation and academic achievement has been established in the literature, further insights into several features of this relationship are still lacking. We therefore present a research agenda where we identify theoretical and methodological challenges that could inspire further understanding of the reciprocal relationship between motivation and achievement as well as inform future interventions. Specifically, the research agenda includes the recommendation that future research considers (1) multiple motivation constructs, (2) behavioral mediators, (3) a network approach, (4) alignment of intervals of measurement and the short vs. long time scales of motivation constructs, (5) designs that meet the criteria for making causal, reciprocal inferences, (6) appropriate statistical models, (7) alternatives to self-reports, (8) different ways of measuring achievement, and (9) generalizability of the reciprocal relations to various developmental, ethnic, and sociocultural groups. [ABSTRACT FROM AUTHOR]

Contextual cues are known to benefit memory retrieval, but whether and how sleep affects this context effect remains unresolved. We manipulated contextual congruence during memory retrieval in human volunteers across 12 h and 24 h intervals beginning with either sleep or wakefulness. Our data suggest that whereas contextual cues lose their potency with time, sleep does not modulate this process. Furthermore, our results are consistent with the idea that sleep's beneficial effect on memory retention depends on the amount of waking time that has passed between encoding and sleep onset. The findings are discussed in the framework of competitive consolidation theory. [ABSTRACT FROM AUTHOR]

Building knowledge schemas that organize information and guide future learning is of great importance in everyday life. Such knowledge building is suggested to occur through reinstatement of prior knowledge during new learning, yielding integration of new with old memories supported by the medial prefrontal cortex (mPFC) and medial temporal lobe (MTL). Congruency with prior knowledge is also known to enhance subsequent memory. Yet, how reactivation and congruency interact to optimize memory integration is unknown. To investigate this question, we used an adapted AB-AC inference paradigm in combination with functional Magnetic Resonance Imaging (fMRI). Participants first studied an AB-association followed by an AC-association, so B (a scene) and C (an object) were indirectly linked through A (a pseudoword). BC-associations were either congruent or incongruent with prior knowledge (e.g. bathduck or hammer in a bathroom), and participants reported subjective B-reactivation strength while learning AC. Behaviorally, both congruency and reactivation enhanced memory integration. In the brain, these behavioral effects related to univariate and multivariate parametric effects in the MTL, mPFC, and Parahippocampal Place Area (PPA). Moreover, mPFC exhibited larger PPA-connectivity for more congruent associations. These outcomes provide insights into the neural mechanisms underlying memory enhancement, which has value for educational learning. [ABSTRACT FROM AUTHOR]

Trial-to-trial feature repetition speeds response times in pop-out visual search tasks. These priming effects are often ascribed to a short-term memory system. Recently, however, it has been reported that a 'build-up' sequence of repetitions could facilitate responses over 16 trials later - well beyond twice the typically reported time course (Vision Research, 2011, 51, 1972-1978). Here, we first report two replication attempts that yielded little to no support for such long-term priming of pop-out. The results instead fell in line with the predictions of a previously proposed computational model that describes priming as short-lived facilitation that decays over approximately eight trials (Vision Research, 2010, 50, 2110-2115). In the second part of this study, we show that these data are consistent with a simple formulation of decay with a single timescale, and that there is no significant priming beyond eight trials. [ABSTRACT FROM AUTHOR]

Despite much research, it remains unclear if dopamine is directly involved in novelty detection or plays a role in orchestrating the subsequent cognitive response. This ambiguity stems in part from a reliance on experimental designs where novelty is manipulated and dopaminergic activity is subsequently observed. Here we adopt the alternative approach: we manipulate dopamine activity using apomorphine (D1/D2 agonist) and measure the change in neurological indices of novelty processing. In separate drug and placebo sessions, participants completed a von Restorff task. Apomorphine speeded and potentiated the novelty-elicited N2, an Event-Related Potential (ERP) component thought to index early aspects of novelty detection, and caused novel-font words to be better recalled. Apomorphine also decreased the amplitude of the novelty-P3a. An increase in D1/D2 receptor activation thus appears to potentiate neural sensitivity to novel stimuli, causing this content to be better encoded. [ABSTRACT FROM AUTHOR]

Functional neuroimaging studies of probabilistic category learning in healthy adults report activation of cortical-striatal circuitry. Based on previous findings of normal learning rate concurrent with an overall performance deficit in patients with schizophrenia, we hypothesized that relative to healthy adults, patients with schizophrenia would display preserved caudate nucleus and abnormal prefrontal cortex activation during probabilistic category learning. Forty patients with schizophrenia receiving antipsychotic medication and 25 healthy participants were assessed on interleaved blocks of probabilistic category learning and control tasks while undergoing blood oxygenation level-dependent functional magnetic resonance imaging. In addition to the whole sample of patients with schizophrenia and healthy adults, a subset of patients and healthy adults matched for good learning was also compared. In the whole sample analysis, patients with schizophrenia displayed impaired performance in conjunction with normal learning rate relative to healthy adults. The matched comparison of patients and healthy adults classified as good learners revealed greater caudate and dorsolateral prefrontal cortex activity in the healthy adults and greater activation in a more rostral region of the dorsolateral prefrontal, cingulate, parahippocampal and parietal cortex in patients. These results demonstrate that successful probabilistic category learning can occur in the absence of normal frontal-striatal function. Based on analyses of the patients and healthy adults matched on learning and performance, a minority of patients with schizophrenia achieve successful probabilistic category learning and performance levels through differential activation of a circumscribed neural network which suggests a compensatory mechanism in patients showing successful learning. [ABSTRACT FROM AUTHOR]