Impairment in attentional processing in a field survival environment

The suggestion that maladaptive behaviour often observed in survival incidents may be due to a restriction in attentional processing was tested using sub‐components of the Test of Everyday Attention in participants undergoing a field survival exercise. Compared to a baseline condition and control group those undergoing environmental duress showed significant impairment in selective and sustained attention which taken together suggests dysfunction in controlled attention. No impairment was found in either attentional switching or auditory‐verbal working memory. It is argued that this type of cognitive impairment makes flexible interaction with the survival environment difficult and the victim's behaviour becomes dominated by environmental cues at the expense of wilful, goal‐directed survival behaviour. This would begin to answer at least one anomaly that exists in survivorship: why so many people perish when there is no need. Copyright © 2007 John Wiley & Sons, Ltd.     

The contribution of executive control to semantic cognition: Convergent evidence from semantic aphasia and executive dysfunction

Semantic cognition, as described by the controlled semantic cognition (CSC) framework (Rogers et al., 2015 , Neuropsychologia, 76, 220), involves two key components: activation of coherent, generalizable concepts within a heteromodal ‘hub’ in combination with modality‐specific features (spokes), and a constraining mechanism that manipulates and gates this knowledge to generate time‐ and task‐appropriate behaviour. Executive–semantic goal representations, largely supported by executive regions such as frontal and parietal cortex, are thought to allow the generation of non‐dominant aspects of knowledge when these are appropriate for the task or context. Semantic aphasia (SA) patients have executive–semantic deficits, and these are correlated with general executive impairment. If the CSC proposal is correct, patients with executive impairment should not only exhibit impaired semantic cognition, but should also show characteristics that align with those observed in SA. This possibility remains largely untested, as patients selected on the basis that they show executive impairment (i.e., with ‘dysexecutive syndrome’) have not been extensively tested on tasks tapping semantic control and have not been previously compared with SA cases. We explored conceptual processing in 12 patients showing symptoms consistent with dysexecutive syndrome (DYS) and 24 SA patients, using a range of multimodal semantic assessments which manipulated control demands. Patients with executive impairments, despite not being selected to show semantic impairments, nevertheless showed parallel patterns to SA cases. They showed strong effects of distractor strength, cues and miscues, and probe–target distance, plus minimal effects of word frequency on comprehension (unlike semantic dementia patients with degradation of conceptual knowledge). This supports a component process account of semantic cognition in which retrieval is shaped by control processes, and confirms that deficits in SA patients reflect difficulty controlling semantic retrieval.     

Divergent thinking: Strategies and executive involvement in generating novel uses for familiar objects

Although the Alternative Uses divergent thinking task has been widely used in psychometric and experimental studies of creativity, the cognitive processes underlying this task have not been examined in detail before the two studies are reported here. In Experiment 1, a verbal protocol analysis study of the Alternative Uses task was carried out with a Think aloud group (N = 40) and a Silent control group (N = 64). The groups did not differ in fluency or novelty of idea production indicating no verbal overshadowing. Analysis of protocols from the Think aloud group suggested that initial responses were based on a strategy of Retrieval from long‐term memory of pre‐known uses. Later responses tended to be based on a small number of other strategies: property‐use generation, imagined Disassembly of the target object into components and scanning of Broad Use categories for possible uses of the target item. Novelty of uses was particularly associated with the Disassembly strategy. Experiment 2 (N = 103) addressed the role of executive processes in generating new and previously known uses by examining individual differences in category fluency, letter fluency and divergent task performance. After completing the task, participants were asked to indicate which of their responses were new for them. It was predicted and found in regression analyses that letter fluency (an executively loading task) was related to production of ‘new’ uses and category fluency was related to production of ‘old’ uses but not vice versa.     

Associations between evaluation anxiety,cognitive interference and performance on working memory tasks

According to Cognitive Interference Theory, evaluation anxiety leads to increased negative off‐task self‐dialogue which then results in diminished cognitive performance. Given that negative off‐task self‐dialogue is primarily verbal, the phonological loop and central executive components of the working memory system should be most affected by evaluation anxiety. Eighty‐eight participants were randomly assigned to receive evaluation anxiety inducing instructions or supportive instructions prior to administration of three tests (Digit Span, Visual Memory Span, and StroopColour‐Word) that measured the phonological loop, visuospatial sketchpad, and central executive components of working memory. Measures of evaluation anxiety and negative off‐task self‐dialogue were obtained during and after testing. Results showed that participants receiving anxiety inducing instructions reported significantly more evaluation anxiety and off‐task self‐dialogue. They also had significantly lower performance on the Digit Span Test and the StroopColour‐Word Test. Negative off‐task self‐dialogue also mediated the relationship between evaluation anxiety and performance on the Digit Span Test. Copyright © 2011 John Wiley & Sons, Ltd.     

Musical Training,Bilingualism, and Executive Function: A Closer Look at Task Switching and Dual‐Task Performance

This study investigated whether musical training and bilingualism are associated with enhancements in specific components of executive function, namely, task switching and dual‐task performance. Participants (n = 153) belonging to one of four groups (monolingual musician, bilingual musician, bilingual non‐musician, or monolingual non‐musician) were matched on age and socioeconomic status and administered task switching and dual‐task paradigms. Results demonstrated reduced global and local switch costs in musicians compared with non‐musicians, suggesting that musical training can contribute to increased efficiency in the ability to shift flexibly between mental sets. On dual‐task performance, musicians also outperformed non‐musicians. There was neither a cognitive advantage for bilinguals relative to monolinguals, nor an interaction between music and language to suggest additive effects of both types of experience. These findings demonstrate that long‐term musical training is associated with improvements in task switching and dual‐task performance.     

The mediating effect of adaptive and maladaptive emotion regulation strategies on executive functioning impairment and depressive symptoms among adolescents

Past research results suggest that executive functioning (EF) impairment represents an important vulnerability factor in depression. Little research, however, has examined mechanisms underlying this association. The current study investigates the associations between EF impairment, emotion regulation (ER) strategies, and depressive symptoms in a sample of 579 adolescents (320 females, mean age = 12.06 years). Parents reported on adolescents’ EF and general psychopathology, and adolescents self-reported ER strategies and depressive symptoms. The results indicate that greater EF impairment is associated with more depressive symptoms. Youth with greater EF impairment reported more maladaptive ER and less adaptive ER, and maladaptive and adaptive ER strategies jointly mediated the association between EF impairment and depressive symptoms. The results highlight an important role of both maladaptive and adaptive ER in explaining the relationship between EF and depressive symptoms and suggest that clinical interventions targeting ER skills may provide one strategy for the prevention and treatment of depression. Further longitudinal research is needed to replicate these results and evaluate the causality of the relations.     

Implication des fonctions exécutives dans le décodage en lecture : étude comparative entre normolecteurs et faibles lecteurs de CE2

The implication of executive functions in reading was studied. Normo and poor third grade readers were compared in an illusory conjunction task using the selection of a letter features embedded in a grapheme or risen to the syllable boundary. Executive task of updating or shifting were then added to this task. According to decoding progress from graphemes to syllables we suppose that the cost of executive processing will be more important for poor readers. Results showed that addition of an executive control task to a selection task, led to an increase in response times for poor readers whatever the presentation (grapheme, syllable).     

Relationship between language switching experience and executive functions in bilinguals: an Internet-based study*

We examined the relationship between self-reported everyday language switching experience and the performance of early bilinguals in tasks measuring different executive functions. Our participants were Finnish–Swedish early bilinguals, aged 16–41 years (N?=?66, Experiment 1) and 18–69 years (N?=?111, Experiment 2). An earlier study using a sample from a similar population discovered a negative relationship between self-reported language switching and a mixing cost in error rates in a number–letter task. This finding was not replicated. Instead, we found that a higher rate of reported contextual language switching predicted larger switching cost reaction times in the number–letter task, and that a higher rate of reported unintended language switches predicted larger error rates in a spatial n-back task. We conclude that these results likely reflect individual differences in executive skills, and do not provide evidence for the hypothesis that language switching trains executive functions.     

“各说各话”的语言经验对景颇族大学生执行功能的影响

在中国云南的景颇族中,相当多的家庭是由不同支系的人组成的,家庭成员交际时存在着"各说各话"的现象。"各说各话"对讲话者的执行功能有无影响?采用抑制控制、注意转换和记忆刷新任务测量各说各话和非各说各话的景颇族大学生的抑制能力、转换能力和刷新能力。结果表明,各说各话与非各说各话的景颇族大学生在色词干扰和数字转换中差异显著,各说各话者的Stroop效应量小,停止信号的反应时短。各说各话与非各说各话的景颇族大学生在数字转换和图形转换中差异显著,各说各话者反应快,转换代价小。各说各话与非各说各话的景颇族大学生在活动记忆刷新与色点位置刷新任务中差异不显著。这表明,各说各话者比非各说各话者在抑制能力与转换能力上具有优势。语言经验对执行功能的影响具有功能特异性。     

The effects of adult aging and induced positive and negative mood on planning

Changes in executive functions have been found in older adults and also in young adults experiencing positive or negative mood states. The current study investigated the hypothesis that older adults would show greater executive function impairment following mood induction than young adults. Ninety-six participants (half aged 19-37, half aged 53-80) completed a neutral, positive, or negative mood induction procedure, followed by the Tower of London planning task. Significant interactions were found between age and mood such that older adults showed greater planning impairment than young adults in both the positive and negative mood conditions. Emotionally salient events occurring before testing may interfere with executive function in older adults.     

Semantic and Phonemic Verbal Fluency in Blinds

A person who has suffered the total loss of a sensory system has, indirectly, suffered a brain lesion. Semantic and phonologic verbal fluency are used for evaluation of executive function and language. The aim of this study is evaluation and comparison of phonemic and semantic verbal fluency in acquired blinds. We compare 137 blinds and 124 sighted people in verbal fluency task. The tasks were phonemic and semantic verbal fluency test that subjects should be generate as many word as possible in a limited amount of time for a given letter (Phonemic fluency) or a given category (Semantic fluency). Independent T Test was used to comparing blind with sighted. Findings show significant difference between two groups so that that sighted subjects have higher performance in semantic verbal fluency task (p = 0.000). Comparing sighted and blind subjects in phonemic verbal fluency task shows performance in sighted subjects (p = 0.000). Based on this study blinds have lower performance in semantic and phonemic verbal fluency task as a executive function of frontal lobe.     

The contribution of executive function and social understanding to preschoolers’ letter and math skills

The influence of executive function and social understanding on letter and math skills was examined in 129 3–5-year-olds. Tasks were administered to measure working memory, inhibition, social understanding, letter and math skills, and vocabulary. Using latent variable analyses, multiple models were compared in order to examine the influence of executive function and social understanding on participants’ emerging academic skills. In the best-fitting model, working memory contributed to letter and math skills, over and above inhibition, social understanding, age, and vocabulary. Inhibition and social understanding did not uniquely contribute to letter and math skills, but significant relations were found among working memory, inhibition, and social understanding. Findings are discussed with respect to improving ways to examine the complex relations among preschoolers’ executive function, social understanding, and school readiness skills.     

进行中任务变化对轻度认知功能障碍者基于事件前瞻记忆的影响

本实验采用2被试组别(MCI组、正常老年组) × 3进行中任务变化(无变化、顺序变化、随机变化)被试间设计探究进行中任务变化对轻度认知功能障碍者基于事件前瞻记忆的影响。结果表明：(1)轻度认知功能障碍者的前瞻记忆成绩显著低于正常老年人的前瞻记忆成绩; (2)进行中任务变化对两组被试前瞻记忆和进行中任务的反应时影响存在显著差异。进行中任务变化越大, 轻度认知功能障碍者完成前瞻记忆和进行中任务的反应速度越慢; 而正常老年被试则不受影响。研究支持前瞻记忆策略加工的理论观点, 认为执行功能损伤可能是导致轻度认知功能障碍者前瞻记忆失败的主要原因。     

Is short‐term memory involved in decision making? Evidence from a short‐term memory patient

It is reasonable to suggest that working memory (WM; Baddeley & Hitch, 1974 ) is involved in decision making, as decision making is dependent on the ability to remember and update past choices and outcomes. However, contradictory results have been reported in the literature concerning the role of two of its components, namely the central executive and the phonological loop. In order to investigate the role of these components in the decision‐making process, we tested a patient with intact central executive but impaired phonological loop on a laboratory decision‐making task involving hypothetical gambles (gambling task, GT). When tested in a no‐load condition (simple keypress task), her performance was not significantly different from that of matched controls. We also verified whether her performance would be affected differently by memory‐load when compared with control subjects. The memory task (holding a string of letters in memory) loaded WM without incurring number‐number interference. When the memory‐load was imposed during the GT, both the patient and the controls showed a decline in performance, but the strategy they adopted differed. Possible explanations are discussed. In conclusion, our results suggest that the phonological loop is not directly involved in decision making.     

Executive and visuospatial sketchpad resources in euthymic bipolar disorder: Implications for visuospatial working memory architecture

Visuospatial working memory theory is used to interpret the cognitive impairment in euthymic bipolar disorder. Such patients show deficits in the Corsi Blocks Test (CBT) and executive control. To understand these deficits, 20 euthymic bipolar patients and controls were administered the CBT, Visual Patterns Test (VPT), and a new visual memory task designed to make minimal demands on executive resources. Initial analyses validated the visual memory task and implicated executive involvement in the CBT and VPT. Subsequent analyses on a number of tests confirmed CBT and executive deficits while performance was normal on the VPT and visual memory test. ANCOVA indicated that impaired executive function underpinned patients' CBT performance. Implications for the interface between executive and slave systems of working memory are discussed.     

Lack of awareness of neuropsychological deficit in cerebral small vessel disease: The relationship with executive and episodic memory functions

A common cause of neuropsychological impairment in older adults is cerebral small vessel disease (SVD), but little is known as to whether lack of awareness of neuropsychological impairment is a feature of this clinical condition. In this study, we investigated awareness deficits in a well‐phenotyped population of patients with SVD (n= 45; 21 with defined concomitant neuropsychological impairment) and made comparisons with 24 Alzheimer's disease (AD) patients and a further 80 control participants. Awareness of performance on a range of neuropsychological measures was examined based on the Brief Memory and Executive Test Battery (BMET) (Brookes, Hannesdottir, Lawrence, Morris, & Markus, 2012 ), exploring the relationship between awareness and memory and executive function. The results revealed significant awareness deficits in both the SVD and AD groups. When splitting the SVD group into those with or without concomitant neuropsychological impairment, only those with neuropsychological impairment showed reduced awareness. For the SVD group, executive function was significantly correlated with awareness but memory was not. By comparison, memory was significantly correlated with awareness in the AD group, with executive function showing a trend but remaining non‐significant. The results show that lack of awareness of deficit is a clinical feature of SVD and indicate that there are distinct neuropsychological associations with awareness deficit for SVD and AD.     

The effects of short-term L2 training on components of executive control in Indian bilinguals

This study investigated whether a short training (8 weeks) in the second-language (English) has any facilitative effect on components of executive functions in young adults. A pre-post design was used with two groups of participants: one group (experimental group) of students received English language training for eight weeks, and another group (control group) matched on age and background did not. Executive function tasks (Flanker, Stroop, and color-shape switching task) along with the object naming and working memory tasks were administered before and after the training. We observed that the experimental group demonstrated significant improvement in task switching, working memory capacity, and language skills. Findings from the study provide evidence that short training in second-language can enhance some components of executive functions besides improving language skills in young adult students. This finding contributes to a better understanding of language training and executive function among young adult bilinguals.

     

Age,working memory,and the Tower of London task

The current study explores the role of three components of working memory in age differences in an executive task, the Tower of London (TOL). The TOL task is sensitive to frontal lobe damage, and is widely used to measure planning ability. Dual tasks were used to test the involvement of the phonological loop (articulatory suppression), visuospatial buffer (pattern tapping), and central executive (random generation) in age effects on the TOL. Older adults showed greater reliance than young on domain-specific verbal and spatial memory components in performing the TOL. In terms of executive function, qualitatively different interference patterns were seen in young and old participants. However, the validity of using random generation tasks to assess executive function in older populations can be questioned. For older participants, performing the TOL loads all components of working memory, whereas for the younger participants the TOL more specifically loads executive functioning.     

The role of the executive system in visuo-spatial memory functioning

Participants were presented with a spatial sequence in which between 4 and 10 cells were highlighted. On each trial list length was unknown to the participant who was required to serially recall the last four cells. Processing of longer lists is assumed to call upon the executive system, which is thought to be involved in updating the contents of the short-term visuo-spatial store. Study 1 revealed that loading the executive system with concurrent random letter generation impaired performance on the spatial task especially recall of the early serial positions. However, contrary to expectation the degree of impairment was no greater on the longer lists, where it had been assumed that updating would be occurring. Study 2 confirmed this finding and demonstrated that relative to sequences of known length, under conditions of uncertainty when the list length was unknown, spatial recall was impaired even on short sequences. The present results support the growing consensus, which is suggestive of closer links between visuo-spatial and executive processes. However, it remains unclear whether or not updating is actually occurring on the longer sequences, and if it is, what specific executive processes are involved.     

Central executive involvement in children's spatial memory

Previous research with adults found that spatial short-term and working memory tasks impose similar demands on executive resources. We administered spatial short-term and working memory tasks to 8- and 11-year-olds in three separate experiments. In Experiments 1 and 2 an executive suppression task (random number generation) was found to impair performances on a short-term memory task (Corsi blocks), a working memory task (letter rotation), and a spatial visualisation task (paper folding). In Experiment 3 an articulatory suppression task only impaired performance on the working memory task. These results suggest that short-term and working memory performances are dependent on executive resources. The degree to which the short-term memory task was dependent on executive resources was expected to be related to the amount of experience children have had with such tasks. Yet we found no significant age-related suppression effects. This was attributed to differences in employment of cognitive strategies by the older children.