Changes In Working Memory Research Articles

Effects of cognitive remediation on negative symptoms dimensions: exploring the role of working memory.

Recent theories suggest that poor working memory (WM) may be the cognitive underpinning of negative symptoms in people with schizophrenia. In this study, we first explore the effect of cognitive remediation (CR) on two clusters of negative symptoms (i.e. expressive and social amotivation), and then assess the relevance of WM gains as a possible mediator of symptom improvement. Data were accessed for 309 people with schizophrenia from the NIMH Database of Cognitive Training and Remediation Studies and a separate study. Approximately half the participants received CR and the rest were allocated to a control condition. All participants were assessed before and after therapy and at follow-up. Expressive negative symptoms and social amotivation symptoms scores were calculated from the Positive and Negative Syndrome Scale. WM was assessed with digit span and letter-number span tests. Participants who received CR had a significant improvement in WM scores (d = 0.27) compared with those in the control condition. Improvements in social amotivation levels approached statistical significance (d = -0.19), but change in expressive negative symptoms did not differ between groups. WM change did not mediate the effect of CR on social amotivation. The results suggest that a course of CR may benefit behavioural negative symptoms. Despite hypotheses linking memory problems with negative symptoms, the current findings do not support the role of this cognitive domain as a significant mediator. The results indicate that WM improves independently from negative symptoms reduction.

Spectral Entropy Can Predict Changes of Working Memory Performance Reduced by Short-Time Training in the Delayed-Match-to-Sample Task.

Spectral entropy, which was generated by applying the Shannon entropy concept to the power distribution of the Fourier-transformed electroencephalograph (EEG), was utilized to measure the uniformity of power spectral density underlying EEG when subjects performed the working memory tasks twice, i.e., before and after training. According to Signed Residual Time (SRT) scores based on response speed and accuracy trade-off, 20 subjects were divided into two groups, namely high-performance and low-performance groups, to undertake working memory (WM) tasks. We found that spectral entropy derived from the retention period of WM on channel FC4 exhibited a high correlation with SRT scores. To this end, spectral entropy was used in support vector machine classifier with linear kernel to differentiate these two groups. Receiver operating characteristics analysis and leave-one out cross-validation (LOOCV) demonstrated that the averaged classification accuracy (CA) was 90.0 and 92.5% for intra-session and inter-session, respectively, indicating that spectral entropy could be used to distinguish these two different WM performance groups successfully. Furthermore, the support vector regression prediction model with radial basis function kernel and the root-mean-square error of prediction revealed that spectral entropy could be utilized to predict SRT scores on individual WM performance. After testing the changes in SRT scores and spectral entropy for each subject by short-time training, we found that 16 in 20 subjects’ SRT scores were clearly promoted after training and 15 in 20 subjects’ SRT scores showed consistent changes with spectral entropy before and after training. The findings revealed that spectral entropy could be a promising indicator to predict individual’s WM changes by training and further provide a novel application about WM for brain–computer interfaces.

The Effects of Home-Based Cognitive Training on Verbal Working Memory and Language Comprehension in Older Adulthood.

Effective language understanding is crucial to maintaining cognitive abilities and learning new information through adulthood. However, age-related declines in working memory (WM) have a robust negative influence on multiple aspects of language comprehension and use, potentially limiting communicative competence. In the current study (N = 41), we examined the effects of a novel home-based computerized cognitive training program targeting verbal WM on changes in verbal WM and language comprehension in healthy older adults relative to an active component-control group. Participants in the WM training group showed non-linear improvements in performance on trained verbal WM tasks. Relative to the active control group, WM training participants also showed improvements on untrained verbal WM tasks and selective improvements across untrained dimensions of language, including sentence memory, verbal fluency, and comprehension of syntactically ambiguous sentences. Though the current study is preliminary in nature, it does provide initial promising evidence that WM training may influence components of language comprehension in adulthood and suggests that home-based training of WM may be a viable option for probing the scope and limits of cognitive plasticity in older adults.

Differences in brain morphology and working memory capacity across childhood.

Working memory (WM) skills are closely associated with learning progress in key areas such as reading and mathematics across childhood. As yet, however, little is known about how the brain systems underpinning WM develop over this critical developmental period. The current study investigated whether and how structural brain correlates of components of the working memory system change over development. Verbal and visuospatial short‐term and working memory were assessed in 153 children between 5.58 and 15.92 years, and latent components of the working memory system were derived. Fractional anisotropy and cortical thickness maps were derived from T1‐weighted and diffusion‐weighted MRI and processed using eigenanatomy decomposition. There was a greater involvement of the corpus callosum and posterior temporal white matter in younger children for performance associated with the executive part of the working memory system. For older children, this was more closely linked with the thickness of the occipitotemporal cortex. These findings suggest that increasing specialization leads to shifts in the contribution of neural substrates over childhood, moving from an early dependence on a distributed system supported by long‐range connections to later reliance on specialized local circuitry. Our findings demonstrate that despite the component factor structure being stable across childhood, the underlying brain systems supporting working memory change. Taking the age of the child into account, and not just their overall score, is likely to be critical for understanding the nature of the limitations on their working memory capacity.

The role of top-down suppression in mitigating the disruptive effects of task-irrelevant feature changes in visual working memory.

Studies of change detection have shown that changing the task-irrelevant features of remembered objects impairs change detection for task-relevant features, a phenomenon known as the irrelevant change effect. Although this effect is pronounced at short study-test intervals, it is eliminated at longer delays. This has prompted the proposal that although all features of attended objects are initially stored together in visual working memory (VWM), top-down control can be used to suppress task-irrelevant features over time. The present study reports the results of three experiments aimed at testing the top-down suppression hypothesis. Experiments 1 and 2 tested whether the magnitude or time course of the irrelevant change effect was affected by the concurrent performance of a demanding executive load task (counting backwards by threes). Contrary to the top-down suppression view, the decreased availability of executive resources did not prolong the duration of the irrelevant change effect in either experiment, as would be expected if these resources were necessary to actively suppress task-irrelevant features. Experiment 3 showed that a visual pattern mask eliminates the irrelevant change effect and suggests that the source of the effect may lie in the use a high-resolution, sensory memory representation to match the memory and test displays when no task-irrelevant feature changes are present. These results suggest that the dissipation of the irrelevant change effect over time likely does not depend on the use of top-down control and raises questions about what can be inferred about the nature of storage in VWM from studies of this effect.

Frontoparietal neurostimulation modulates working memory training benefits and oscillatory synchronization

There is considerable interest in maintaining working memory (WM) because it is essential to accomplish most cognitive tasks, and it is correlated with fluid intelligence and ecologically valid measures of daily living. Toward this end, WM training protocols aim to improve WM capacity and extend improvements to unpracticed domains, yet success is limited. One emerging approach is to couple WM training with transcranial direct current stimulation (tDCS). This pairing of WM training with tDCS in longitudinal designs promotes behavioral improvement and evidence of transfer of performance gains to untrained WM tasks. However, the mechanism(s) underlying tDCS-linked training benefits remain unclear. Our goal was to gain purchase on this question by recording high-density EEG before and after a weeklong WM training+tDCS study. Participants completed four sessions of frontoparietal tDCS (active anodal or sham) during which they performed a visuospatial WM change detection task. Participants who received active anodal tDCS demonstrated significant improvement on the WM task, unlike those who received sham stimulation. Importantly, this pattern was mirrored by neural correlates in spectral and phase synchrony analyses of the HD-EEG data. Notably, the behavioral interaction was echoed by interactions in frontal-posterior alpha band power, and theta and low alpha oscillations. These findings indicate that one mechanism by which paired tDCS+WM training operates is to enhance cortical efficiency and connectivity in task-relevant networks.

Reduced Theta Coherence and P Wave Ratio Linked to Memory Deficits After Sleep Deprivation in Rat Model

It is well established that loss of sleep leads to lapses in learning and memory. The brain regions including hippocampus, amygdala and the prefrontal cortex are associated with memory processes. However, there are not many studies on the changes in neuronal communications between these brain areas during sleep deprivation. In this study, changes in the P waves, and theta coherence among the hippocampus, amygdala and the prefrontal cortex, were studied before and after exposing the animals to total sleep deprivation of 24 h. Changes in reference and working memory were evaluated after sleep deprivation. Concomitant with a rebound increase in non-REM sleep after total sleep deprivation, there was a decrease in the coherence of theta waves between all the studied areas, especially between hippocampus and amygdala. The ratio of P wave cluster to singlet was reduced. There was a decrease in ‘correct memory performance’ after sleep deprivation. This study showed that after sleep deprivation, there was a correlation in the cognitive deficits and decrease in the coherence of theta waves, and the ratio of P wave cluster to singlet. Impairments in brain function, especially cognition, after sleep loss could be attributed to changes in functional connectivity between these neural networks. This study highlighted important functions of sleep in maintaining an appropriate synchrony between various neuronal networks during REM sleep.

The Ratio of HDL to LDL in Serum Is Related to Macular Pigment Density and Cognitive Function in Older Adults: Potential Insights into Lutein Transport to Neural Tissue

The dietary carotenoid, lutein, is selectively taken up into neural tissue. Neural lutein is related to better cognition. However, serum lutein concentrations may not accurately reflect neural levels. Lutein is mainly transported on high‐density lipoprotein (HDL) followed by low‐density lipoprotein (LDL). HDL may play a significant role in delivery of lipophilic nutrients to neural tissue. Therefore, lutein content on HDL may better reflect neural levels. However, this has yet to be investigated in humans. The relative amounts of HDL and LDL (HDL/LDL) is an indicator of the distribution of lutein in the circulation. The aim of this study was to determine the relationship between changes in lipoprotein profiles, neural lutein concentration (measured by macular pigment density, MPD), and cognitive performance in older adults (n=31) using a previously conducted study in which participants were followed for 6 months. Serum collection, MPD (using heterochromatic flicker photometry), and cognitive testing (computerized cognitive assessment battery, CANTAB) were performed at baseline, 3 months, and 6 months. Serum lipoproteins and carotenoids were determined using an enzymatic colorimetric method and HPLC, respectively. There was a group of individuals who had MPD increases >0.10 optical density (OD) over the study period (n=17). These subjects were classified as “MPD responders”. In these subjects, adjusting for age, change in HDL/LDL was positively associated with change in MPD (r=0.66, p=0.006) and the strength of this association was greater in a subset of MPD responders who also had increases in serum lutein (n=10, r=0.77, p=0.01). The association between change in HDL/LDL and MPD was not significant in MPD responders without increases in serum lutein. In all MPD responders, change in both HDL/LDL and MPD were positively associated with change in spatial working memory and increased spatial planning, while change in serum lutein was positively related to spatial planning only (adjusted for age and education, P<0.05). Associations between HDL/LDL and cognition were stronger in the subset of MPD responders who also had increases in serum lutein (P<0.05). In MPD non‐responders (ΔMPD ≤0.05 OD), HDL/LDL was not related to MPD, but was associated with spatial planning. Collectively, these findings lend support to the hypothesis that lutein carried on HDL is targeted to neural tissue and may be important for cognition.Support or Funding InformationThis work was supported by the Hass Avocado Board and USDA (1950‐51000‐087)

Functional neuroanatomical associations of working memory in early-onset Alzheimer's disease.

To characterize metabolic correlates of working memory impairment in clinically defined subtypes of early-onset Alzheimer's disease. Established models of working memory suggest a key role for frontal lobe function, yet the association in Alzheimer's disease between working memory impairment and visuospatial and language symptoms suggests that temporoparietal neocortical dysfunction may be responsible. Twenty-four patients with predominantly early-onset Alzheimer's disease were clinically classified into groups with predominantly amnestic, multidomain or visual deficits. Patients underwent neuropsychological evaluation focused on the domains of episodic and working memory, T1-weighted magnetic resonance imaging and brain fluorodeoxyglucose positron emission tomography. Fluorodeoxyglucose positron emission tomography data were analysed by using a region-of-interest approach. Patients with multidomain and visual presentations performed more poorly on tests of working memory compared with amnestic Alzheimer's disease. Working memory performance correlated with glucose metabolism in left-sided temporoparietal, but not frontal neocortex. Carriers of the apolipoprotein E4 gene showed poorer episodic memory and better working memory performance compared with noncarriers. Our findings support the hypothesis that working memory changes in early-onset Alzheimer's disease are related to temporoparietal rather than frontal hypometabolism and show dissociation from episodic memory performance. They further support the concept of subtypes of Alzheimer's disease with distinct cognitive profiles due to prominent neocortical dysfunction early in the disease course. Copyright © 2017 John Wiley & Sons, Ltd.

P255 Electrophysiological and behavioral monitoring of learning: An EEG and tRNS combined study

Question Improving cognitive abilities by means of training and brain stimulation has often been reported ( Elmasry et al., 2015 ). However, the specific electrophysiological and cognitive processes underlying these improvements are still overlooked. In order to investigate the behavioural and electrophysiological effects of brain stimulation on learning, we designed a training study of visual working memory and inhibitory abilities. Our main goal was to characterize the behavioral and brain oscillatory correlates of training, combined or not with tRNS. Methods Thirty healthy young participants were tested before and after being trained for 4 consecutive days. Half of the participants received training coupled with parietal brain stimulation (tRNS), half coupled with sham. We used an established retrocueing paradigm ( Pertzov et al., 2013 ), which provides an index of WM precision as well as of inhibitory abilities, which are critical for memory recall ( Gazzaley et al., 2005 ). Electrophysiological activity was recorded for the entire duration of the training. Frequency specific changes of the ongoing EEG activity were analysed using Morlet wavelet decomposition. Results We found a significant amelioration in inhibitory abilities and in the precision of the memory trace, particularly in the tRNS group. Electrophysiologically, these changes were explained by parietal alpha desynchronization in both groups as well as decreased frontal theta synchronization in the tRNS group. Conclusion Training induced changes in visual working memory and inhibitory abilities can be monitored behaviorally and electrophysiologically. Here, theta driven modulation of top-down attention and alpha driven modulation of inhibitory abilities explain tRNS and training-related changes in performance.

Working memory decline in normal aging: Is it really worse in space than in color?

Aging is associated with a variety of changes in cognitive capacities, including a decline in working memory performance. Nevertheless, visuo-spatial working memory has been shown to exhibit a greater age-related decline than verbal working memory. Here, we assessed age-related changes in allocentric spatial working memory and color working memory. We tested 20–30-year-old and 65–75-year-old adults on four memory tasks requiring participants to learn, on a repeated-trial basis (i.e., reference memory) or a trial-unique basis (i.e., working memory), the locations or colors of three pads among 18 pads distributed in a real-world laboratory environment. Older adults performed worse than young adults on all memory tasks, but especially on working memory tasks. Some measures, including the older adults’ relative decrease in the number of correct choices before erring (CBE), as compared to young adults, and the number of trials with the first or first two choices correct, may suggest a greater age-related decline in allocentric spatial than color working memory. In contrast, the total number of disks visited to find the goals, the absolute decrease in CBE in older adults, the number of errorless trials and the number of trials with the first three choices correct revealed no age-related differences in working memory performance for spatial versus color information. We discuss how, depending on the measures used to evaluate memory performance, age-related declines in working memory may appear greater for spatial information because allocentric spatial memory may have quantitatively greater representational demands (i.e., require more bits of information) than color memory.

The unconscious nature of insight: A dual-task paradigm investigation

Background. Insight is a specific part of the thinking process during creative problem solving. The experience of a sudden unexpected solution of the problem makes it distinct from other problem solving. Though the insight problem solving process is hidden from the observer and the solver himself, it is possible to study working memory changes during the problem-solving process in order to observe the tracks of insight.

Working memory outcomes following unilateral arterial ischemic stroke in childhood

ABSTRACTThere is a dearth of research examining working memory (WM) following pediatric arterial ischemic stroke (AIS). This study assesses the WM patterns of 32 children, aged 6 to 14 years, with a history of unilateral AIS and 32 controls using a paradigm based on Baddeley and Hitch’s multi-component WM model. The results indicate compromised WM in children with AIS relative to controls and parent reports confirm higher rates of dysfunction. Supplementary analyses of impairment confirm higher rates in children with AIS, ranging from 31.25% to 38.70% on performance-based measures and 50.00% on parent reports, compared to 0.00% to 21.88% on performance-based measures in controls and 15.63% on parent reports. Continual follow-up is recommended given that a subset of children with stroke appear to be at risk for WM impairment. Moreover, the subtle nature of WM challenges experienced by many children who have experienced a stroke increases the likelihood that WM impairment could go undetected. The long-term trajectories of WM in the pediatric stroke population remains unknown and future studies are needed to track changes in WM functioning over time.

Physical and Cognitive Performance Effects of Caffeine in Women and Men Exercising in the Heat

Acute caffeine ingestion is considered effective in improving endurance capacity. Caffeine may also improve cognitive functions and mood. However, current knowledge about the effects of caffeine is based on the findings of studies which mainly have been conducted in temperate environmental conditions and on male subjects, whereas some physiological and mood effects of caffeine have been shown to differ between sexes. PURPOSE: The aim of this study was to compare physical and cognitive performance effects of caffeine in young women and men during constant-load treadmill walk to exhaustion in the heat. METHODS: Thirteen male (age 24.9±4.1 yr, height 1.83±0.06 m, body mass 78.8±7.9 kg, VO2peak 51.7±2.7 ml·kg−1·min−1) and ten female (age 22.5±2.0 yr, height 1.67±0.05 m, body mass 61.0±5.4 kg, VO2peak 45.6±4.0 ml·kg−1·min−1) physically active students completed two constant-load walks (60% VO2peak) on a treadmill until volitional exhaustion in a climatic chamber (air temperature 42°C and relative humidity 20%) after caffeine (CAF) and placebo (wheat flour; PLC) ingestion in a double-blind, randomly assigned, crossover manner. Both CAF and PLC were administered in gelatine capsules in 2 doses: 60 min (4 mg/kg) and immediately (2 mg/kg) prior to exercise. RESULTS: Walking time to exhaustion was 82±15 min and 76±11 min (p>0.05) in females and 83±17 min and 82±14 min (p>0.05) in males in PLC and CAF trial, respectively. CAF compared to PLC increased (p<0.05) heart rate and blood lactate concentration in both males and females, but had no impact (p>0.05) on changes in rectal and mean weighted skin temperature during walk to exhaustion. CAF had no impact (p>0.05) on changes in mood, short-term memory and working memory during exercise in either gender, however, CAF compared to PLC decreased (p<0.05) ratings of perceived exertion and fatigue in males, but not in females. In females, but not in males, stronger belief that they had administered CAF associated with shorter time to exhaustion. CONCLUSION: In both males and females, caffeine has no impact on endurance capacity, cognitive performance or mood under hot environmental conditions. Supported by the Estonian Ministry of Education and Research, institutional research funding IUT 20-58.

Neurodevelopmental Deceleration by Urban Fine Particles from Different Emission Sources: A Longitudinal Observational Study.

Background:A few studies have reported associations between traffic-related air pollution exposure at schools and cognitive development. The role of PM components or sources other than traffic on cognitive development has been little explored.Objectives:We aimed to explore the role of PM sources in school air on cognitive development.Methods:A cohort of 2,618 schoolchildren (average age, 8.5 years) belonging to 39 schools in Barcelona (Spain) was followed up for a year. Children completed computerized tests assessing working memory, superior working memory, and inattentiveness during four visits. Particulate matter ≤ 2.5 μm (PM2.5) was measured during two 1-week campaigns in each school, both outdoors and in the classroom. Source apportionment resulted in nine sources: mineral, organic/textile/chalk, traffic, secondary sulfate and organics, secondary nitrate, road dust, metallurgy, sea spray, and heavy oil combustion. Differences in cognitive growth trajectories were assessed with mixed models with age-by-source interaction terms.Results:An interquartile range increase in indoor traffic-related PM2.5 was associated with reductions in cognitive growth equivalent to 22% (95% CI: 2%, 42%) of the annual change in working memory, 30% (95% CI: 6%, 54%) of the annual change in superior working memory, and 11% (95% CI: 0%, 22%) of the annual change in the inattentiveness scale. None of the other PM2.5 sources was associated with adverse effects on cognitive development.Conclusions:Traffic was the only source of fine particles associated with a reduction in cognitive development. Reducing air pollution from traffic at primary schools may result in beneficial effects on cognition.Citation:Basagaña X, Esnaola M, Rivas I, Amato F, Alvarez-Pedrerol M, Forns J, López-Vicente M, Pujol J, Nieuwenhuijsen M, Querol X, Sunyer J. 2016. Neurodevelopmental deceleration by urban fine particles from different emission sources: a longitudinal observational study. Environ Health Perspect 124:1630–1636; http://dx.doi.org/10.1289/EHP209

Object representations in visual working memory change according to the task context

This study investigated whether an item's representation in visual working memory (VWM) can be updated according to changes in the global task context. We used a modified change detection paradigm, in which the items moved before the retention interval. In all of the experiments, we presented identical color–color conjunction items that were arranged to provide a common fate Gestalt grouping cue during their movement. Task context was manipulated by adding a condition highlighting either the integrated interpretation of the conjunction items or their individuated interpretation. We monitored the contralateral delay activity (CDA) as an online marker of VWM. Experiment 1 employed only a minimal global context; the conjunction items were integrated during their movement, but then were partially individuated, at a late stage of the retention interval. The same conjunction items were perfectly integrated in an integration context (Experiment 2). An individuation context successfully produced strong individuation, already during the movement, overriding Gestalt grouping cues (Experiment 3). In Experiment 4, a short priming of the individuation context managed to individuate the conjunction items immediately after the Gestalt cue was no longer available. Thus, the representations of identical items changed according to the task context, suggesting that VWM interprets incoming input according to global factors which can override perceptual cues.

Insight in bipolar disorder through the course of manic episode and its clinical correlates

IntroductionInsight is a well-documented phenomenon for psychotic disorders. It has been studied extensively in schizophrenia and its association with clinical outcomes has drawn increased attention. Although less is known for affective disorders, recent studies point out that impaired insight in bipolar disorder may take part in patients’ overall well-being.AimsExploring the main components of insight in psychiatry, particularly in bipolar disorder.ObjectivesWith this study, we wanted to examine how clinical and cognitive insights change in patients with bipolar disorder through their hospitalization period and how they correlate with symptom severity and neuropsychological functioning.MethodsIn this prospective study, inpatients with bipolar I disorder who were presented by manic episode with psychotic features were included. The patients were assessed with Young Mania Rating Scale, Beck Cognitive Insight Scale, Schedule for the Assessment of Insight-Expanded Version (SAI-E) and a neuropsychological test battery both at the time of admission and discharge.ResultsAs of October 2015, a total number of 20 patients with bipolar I disorder participated in the study. Preliminary results revealed a significant improvement in the total score of clinical insight, which was measured with SAI-E by the time of discharge (P = 0.001). This transition was strongly correlated with the decrease in symptom severity (P = 0.006, r = −0.61). Improved clinical insight exhibited significant correlation with the increase in patients’ memory span (P = 0.007, r = −0.596).ConclusionThe preliminary results suggest that changes in symptom severity and working memory might be the determinants of improvement in clinical insight of inpatients with bipolar disorder through manic episode.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Application of Neuro-Cognitive Assessment and Rehabilitation (NCAR) Computerized Test in Working Memory Deficit in Parkinson

Patients with Parkinson have working memory changes, so they need rehabilitation and treatment is required for them. The purpose of current study is to determine the effect of neuro-cognitive rehabilitation computerized test on these impairments. The present cross-sectional study was conducted on 120 patients with Parkinson and neuro-cognitive rehabilitation computerized test were used for assessment (before) and rehabilitation (after) in patients in 15 minutes. Before and after neuro-cognitive rehabilitation, a significant difference was identified in neuro-cognitive rehabilitation computerized test’ scores (P<0.000). This technique can rehab in Parkinson with working memory disorders associated with neurological conditions to facilitate the acquisition.

Predictors of trajectories of cognitive change in women with breast cancer.

149 Background: Subgroups of women with breast cancer may be vulnerable to cognitive changes with systemic therapy. Given our previous findings of changes in concentration and working memory (WM), we sought to identify subgroups of women with distinct trajectories of concentration and WM and determine predictors of subgroup membership. Methods: Cognitive function was assessed before systemic therapy and semi-annually to 18 months post-therapy initiation in 181 postmenopausal women with breast cancer who received the AI, anastrozole, or chemotherapy+anastrozole and at matched time points for 110 healthy controls. Group-based trajectory modeling identified subgroups of women with distinct trajectories of concentration and WM (as measured by composites of mean z-scores for neuropsychological tests). Multinomial logistic regression identified predictors of subgroup membership. Results: A 3-group model was found for concentration: low and constant (25%; b0 = -0.84), normal but declining (65%; b0 = 0.05, b1 = -0.04), and high and constant (10%; b0 = 1.29). At baseline, the low subgroup was older (p = .009) and had lower psychomotor speed (p = .035) than the normal subgroup. Controlling for baseline concentration z-scores, membership in the low concentration subgroup was associated with greater age (p &lt; .001), more fatigue (p &lt; .001), and poorer self-reported cognitive function (p = .001). For WM, a 2-group model was identified: low and increasing (35%; b0 = -0.67, b1 = 0.11) and high and increasing (65%; b0 = 0.32, b1 = 0.07). At baseline, the low WM subgroup was older (p = .008), had less education (p &lt; .001), and scored lower on the NART verbal IQ test (p &lt; .001). Controlling for baseline WM z-scores, membership in the low WM subgroup was associated with poorer executive function (p &lt; .001), receipt of anastrozole alone (p = .011), and worse pain (p = .002) and anxiety (p = .008). Conclusions: Subgroups of women are more vulnerable to poorer concentration and WM during adjuvant therapy for breast cancer. Advancing age, less education, and co-occurring symptoms are associated with membership in these vulnerable subgroups.

Modulation of Alpha and Beta Oscillations during an n-back Task with Varying Temporal Memory Load.

Temporal information can be retained and manipulated in working memory (WM). Neural oscillatory changes in WM were examined by varying temporal WM load. Electroencephalography was obtained from 18 subjects performing a temporal version of the visual n-back WM task (n = 1 or 2). Electroencephalography revealed that posterior alpha power decreased and temporal region-distributed beta power increased as WM load increased. This result is consistent with previous findings that posterior alpha band reflects inhibition of task-irrelevant information. Furthermore, findings from this study suggest that temporal region-distributed beta band activity is engaged in the active maintenance of temporal duration in WM.