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 IMAGO DEI AS A WORK IN PROGRESS: A PERSPECTIVE FROM PALEOANTHROPOLOGY

This article considers the imago Dei from the perspective of paleoanthropology. We identify structural, functional, and relational elements of the imago Dei that emerged mosaically during human evolution. Humans are unique in their ability to relate to each other and to God, and in their membership of cultural communities where shared attention, the transmission of moral norms, and symbolic behavior are important elements. We discuss similarities between our approach and the concept of theosis adopted in the Eastern Orthodox Church.     

Do goal cue and motor activity impact preschoolers’ working memory?

Preschoolers are well known for their poor working memory (WM) performance. This could result from goal neglect, which would hamper the setting of maintenance strategies. Previous studies have shown that preschoolers’ WM performance can be improved in game-like tasks, because they provide cues to support goal maintenance. However, in these studies, it was unclear what features of the task (either the main toy or the motor activity required by the game) provide efficient cues. The aim of the present study was to disentangle the two features to examine cue effects in 5- to 7-year-old children. No improvement of WM performance was observed when the toy was a potential goal cue, whereas the motor activity had a detrimental effect in all age groups. The latter effect could result from a distraction of attention from attention-based maintenance activities. Hence, preschoolers' poor WM performance would not be fundamentally due to goal neglect.     

Effects of irrelevant object structure on early attention deployment

Event-related potential (ERP) studies have suggested that Gestalt principles or grouping factors in a visual scene modulate attention deployment in early visual processing. The present study examined the effects of an extrinsic grouping factor, region commonality, on early ERP spatial attention. Effects of sex were also explored, since the processing of task-irrelvant objects may differ between the sexes. Twenty-four participants were required to discriminate one side of rapidly-presented bilateral letters, and attention effects were indexed by hemispheric lateralization accroding to attended visual fields. In results, an early P1 attention effect (70–110 ms) increased when the letters were surrounded by an object, compared to the control stimulus without a complete object, and this result was more prominent in women than in men. The present study demonstrates that visual object and sex differences play a novel role at very early cortical stages of processing in attention deployment to a task-irrelevant visual structure.     

急性应激损害对威胁刺激的注意解除

急性应激会增强个体对威胁刺激的注意偏向,但急性应激是增强了对威胁刺激的注意定向还是损害了对威胁刺激的注意解除还不清楚。本研究采用社会评估冷压任务和点探测任务,结合事件相关电位技术,考察急性应激对威胁刺激注意偏向影响的认知机制。在进行社会评估冷压任务后,应激组个体的状态焦虑和皮质醇浓度显著升高。在注意偏向中,应激组对威胁刺激的注意解除比控制组更慢,应激组和控制组在对威胁刺激的注意定向上无显著差异。ERP结果上,威胁刺激诱发应激组比控制组产生了更负的SPCN,在N2pc上没有显著差异。应激组和控制组皮质醇增量的差异和N2pc、SPCN的组间差异均有显著正相关。这些结果说明,急性应激增强对威胁刺激的注意偏向是因为其损害个体对威胁刺激的注意解除,这可能是因为急性应激损害了与注意解除相关的额-顶网络的功能所致。     

内源性注意和外源性注意的ERP研究

内源性注意和外源性注意反映注意指向与集中的自上而下和自下而上的加工。大量事件相关电位的ERP研究考察了内源性注意和外源性注意的神经活动机制。内源性注意诱发了早期N1成分和晚期P300成分,是否诱发P1成分的研究结果不尽一致;外源性注意加强了N1成分、P1成分以及P300成分。研究还表明内源性注意和外源性注意是两种独立的注意系统,以不同的方式影响着脑内的信息加工     

Both fearful and happy expressions interact with gaze direction by 200 ms SOA to speed attention orienting

Attention orienting towards a gazed-at location is fundamental to social attention. Whether gaze cues can interact with emotional expressions other than those signalling environmental threat to modulate this gaze cueing, and whether this integration changes over time, remains unclear. With four experiments we demonstrate that, when perceived motion inherent to dynamic displays is controlled for, gaze cueing is enhanced by both fearful and happy faces compared to neutral faces. This enhancement is seen with stimulus-onset asynchronies ranging from 200–700?ms. Thus, gaze cueing can be reliably modulated by positive expressions, albeit to a smaller degree than fearful ones, and this gaze–emotion integration impacts behaviour as early as 200?ms post-cue onset.     

A psychometric comparison of anxiety-relevant attention measures

Background and Objectives: Preferential attention to threat, emotional response inhibition, and attentional control each purportedly play a key role in anxiety disorders. Divergent psychometric properties among attention measures may produce differential detection of anxiety-related associations and treatment-related changes. However, no studies have directly compared the psychometric properties of these attention measures in the same sample.

Design: Eighty-five young adults (M?=?19.41 years, SD?=?1.47, 48 Females) completed a cognitive task battery and a subset of 60 participants (M?=?19.42 years, SD?=?1.48, 33 Females) completed the task battery again approximately two weeks later.

Method: To assess preferential attention to threat, emotional response inhibition, and attentional control, the cognitive task battery included a dot-probe task, emotion and gender Stroop tasks, and a flanker task. Tasks varied in how attention was directed and if emotional stimuli were included. Internal consistency and test-retest reliability were compared across measures.

Results: Within the same sample, internal consistency and reliability differed across attention measures. Explicit attention measures (emotional Stroop and flanker) exhibited stronger internal consistency and greater test-retest reliability compared to implicit measures (dot-probe and gender Stroop).

Conclusions: These results inform clinical research using attention measures to assess anxiety-related differences and treatment response.     

Visual attention control differences in 12-month-old preterm infants

There have been few previous attempts to assess the development of early markers of executive function in infants born preterm despite well-established deficits reported for older preterm children that have been closely linked to poorer academic functioning. The present study investigates early attention control development in healthy 12-month-old age-corrected pre-term infants who were born less than 30 weeks and compares their performance to full-term infants. Eye-tracking methodology was used to measure attention control. Preterm Infants spent less time focused on the target and were slower to fixate attention, with lower gestational age associated with poorer target fixation and slower processing speed. There were no significant group differences observed for inhibition of return or interference control. These findings suggest that specific emerging deficits in attention control may be observed using eye tracking methodology in very preterm infants at this early stage of development, despite scores within the average range on the Bayley Scales of Infant Development.