Working memory retrieval differences between medial temporal lobe epilepsy patients and controls: A three memory layer approach

Multi-store models of working memory (WM) have given way to more dynamic approaches that conceive WM as an activated subset of long-term memory (LTM). The resulting framework considers that memory representations are governed by a hierarchy of accessibility. The activated part of LTM holds representations in a heightened state of activation, some of which can reach a state of immediate accessibility according to task demands. Recent neuroimaging studies have studied the neural basis of retrieval information with different states of accessibility. It was found that the medial temporal lobe (MTL) was involved in retrieving information within immediate access store and outside this privileged zone. In the current study we further explored the contribution of MTL to WM retrieval by analyzing the consequences of MTL damage to this process considering the state of accessibility of memory representations. The performance of a group of epilepsy patients with left hippocampal sclerosis in a 12-item recognition task was compared with that of a healthy control group. We adopted an embedded model of WM that distinguishes three components: the activated LTM, the region of direct access, and a single-item focus of attention. Groups did not differ when retrieving information from single-item focus, but patients were less accurate retrieving information outside focal attention, either items from LTM or items expected to be in the WM range. Analyses focused on items held in the direct access buffer showed that consequences of MTL damage were modulated by the level of accessibility of memory representations, producing a reduced capacity.     

The Interplay Between Trust Among Peers and Interpersonal Characteristics in Homophobic Bullying Among Italian Adolescents

This study is based on exploring the trust between peers and the individual characteristics related to homophobic bullying in adolescence. Participants were 334 adolescents (141 boys and 193 girls) aged from 15 to 20 years. Participants completed the homophobic bullying scale, to investigate bullying actions towards sexual minorities, the personal attributes questionnaire, for personal characteristics, and the inventory of parent and peer attachment, to the trust between peers. The results demonstrated how female participants manifested a higher level of interpersonal traits and trust among peers than boys. Results showed how a lack of trust between peers predicts homophobic bullying. Nevertheless, we found that the lack of interpersonal characteristics represents a variable that likely mediates the relationship between lack of trust in peers and homophobic bullying. Theoretical and practical implications are discussed.     

The effects of expected reward on creative problem solving

Creative problem solving involves search processes, and it is known to be hard to motivate. Reward cues have been found to enhance performance across a range of tasks, even when cues are presented subliminally, without being consciously detected. It is uncertain whether motivational processes, such as reward, can influence problem solving. We tested the effect of supraliminal and subliminal reward on participant performance on problem solving that can be solved by deliberate analysis or by insight. Forty-one participants attempted to solve 100 compound remote associate problems. At the beginning of each problem, a potential reward cue (1 or 25 cents) was displayed, either subliminally (17 ms) or supraliminally (100 ms). Participants earned the displayed reward if they solved the problem correctly. Results showed that the higher subliminal reward increased the percentage of problems solved correctly overall. Second, we explored if subliminal rewards preferentially influenced solutions that were achieved via a sudden insight (mostly processed below awareness) or via a deliberate analysis. Participants solved more problems via insight following high subliminal reward when compared with low subliminal reward, and compared with high supraliminal reward, with no corresponding effect on analytic solving. Striatal dopamine (DA) is thought to influence motivation, reinforce behavior, and facilitate cognition. We speculate that subliminal rewards activate the striatal DA system, enhancing the kinds of automatic integrative processes that lead to more creative strategies for problem solving, without increasing the selectivity of attention, which could impede insight.     

Cross-Age Peer Tutoring and Fluency-Based Instruction to Achieve Fluency with Mathematics Computation Skills: A Randomized Controlled Trial

The current study employed a randomized controlled trial to evaluate the use of peer tutoring and fluency-based instruction to increase mathematics fluency with addition and subtraction computation skills. Forty-one elementary school students between the ages of eight and 12 years participated in the 8-week study using cross-age peer tutoring, Say All Fast Minute Every Day Shuffled, frequency building, and the morningside math facts curriculum (Johnson in Morningside mathematics fluency: math facts (vol 1–6; curriculum program), Morningside Press, Seattle, 2008). Pre- and post-test measures of mathematics fluency and calculation were conducted with all participants. A measure of social skills and competing problem behaviors was also conducted at pre- and post-testing to evaluate any additional effects of the peer tutoring model. The results demonstrated a statistically significant difference between groups on measures of mathematics fluency, with the experimental group demonstrating significantly higher scores than the control group at post-testing. There were no significant differences between groups on measures of social skills and competing problem behaviors or calculation. The findings indicate that cross-age peer tutoring and fluency-based instruction resulted in positive outcomes for tutees in the mathematics domain, specifically mathematics fluency.     

Benefits of team participative decision making and its potential to affect individual creativity

How does team participative decision‐making affect individual creative performance? Building on team climate theory (Anderson & West, 1998; West 1990, 2002; West & Sacramento, 2012), this study investigates the indirect effect of team participative decision making on employee creativity through individual perception of cognition team diversity and psychological safety. Results from 256 supervisor–subordinate dyads in 45 teams show that team participative decision making is positively associated with cognitive team diversity and psychological safety. For the mediating effects, team participative decision‐making climate is positively indirectly related to creative performance via psychological safety but not via cognitive team diversity. Theoretical and practical implications are discussed.     

Individual Differences in Commitment to Value‐Based Beliefs and the Amplification of Perceived Belief Dissimilarity Effects

The commitment to beliefs (CTB) framework (Maxwell‐Smith & Esses, 2012) proposes that there are individual differences in the extent to which people generally follow beliefs that are a reflection of their values. The current research hypothesized that CTB would amplify the effects of perceived belief dissimilarity or incompatibility, such that individuals higher in CTB would display more pronounced reactions to belief‐relevant groups, events, or individuals seen as incompatible with their value‐based beliefs. We tested our hypothesis in three studies that assessed participants' CTB and their perceptions of belief dissimilarity or incompatibility with regard to other religious groups (Study 1), political parties during a national election (Study 2), and their romantic partner (Study 3). CTB amplified the effects of perceived belief dissimilarity or incompatibility on people's biases toward other religious groups, voting intentions and behavior in a national election, and their evaluative and behavioral responses toward their romantic partner. These results collectively suggest that perceptions of belief dissimilarity or incompatibility are particularly important cues for individuals with higher levels of CTB as they encounter other people or events that are relevant to their beliefs.     

Sleep deprivation impairs object recognition in mice

Many studies in animals and humans suggest that sleep facilitates learning, memory consolidation, and retrieval. Moreover, sleep deprivation (SD) incurred after learning, impaired memory in humans, mice, rats, and hamsters. We investigated the importance of sleep and its timing in an object recognition task in OF1 mice subjected to 6h SD either immediately after the acquisition phase (0-6 SD) or 6h later (7-12 SD), and in corresponding undisturbed controls. Motor activity was continuously recorded with infrared sensors. All groups explored two familiar, previously encountered objects to a similar extent, both at the end of the acquisition phase and 24h later during the test phase, indicating intact familiarity detection. During the test phase 0-6 SD mice failed to discriminate between the single novel and the two familiar objects. In contrast, the 7-12 SD group and the two control groups explored the novel object significantly longer than the two familiar objects. Plasma corticosterone levels determined after SD did not differ from time-matched undisturbed controls, but were significantly below the level measured after learning alone. ACTH did not differ between the groups. Therefore, it is unlikely that stress contributed to the memory impairment. We conclude that the loss of sleep and the activities the mice engaged in during the SD, impaired recognition memory retrieval, when they occurred immediately after acquisition. The delayed SD enabled memory consolidation during the 6h when the mice were allowed to sleep, and had no detrimental effect on memory. Neither SD schedule impaired object familiarity processing, suggesting that only specific cognitive abilities were sensitive to the intervention. Sleep may either actively promote memory formation, or alternatively, sleep may provide optimal conditions of non-interference for consolidation.