Behavioural and neurophysiological differences in working memory function of depressed patients and healthy controls

Objective: Major depressive disorder (MDD) is associated with deficits in working memory. Several cognitive subprocesses interact to produce working memory, including attention, encoding, maintenenace and manipulation. We sought to clarify the contribution of functional deficits in these subprocesses in MDD by varying cognitive load during a working memory task.Methods: 41 depressed participants and 41 age- and gender-matched healthy controls performed the n-back working memory task at three levels of difficulty (0-, 1-, and 2-back) in a pregistered study. We assessed response times, accuracy, and event-related electroencephalography (EEG), including P2 and P3 amplitudes, and frontal theta power (4-8 Hz). Results: MDD participants had prolonged response times and more positive P3 amplitudes relative to controls. Working memory accuracy, P2 amplitudes and frontal theta event-related synchronisation did not differ between groups at any level of task difficulty.Conclusions: Depression is associated with generalized psychomotor slowing of working memory processes, as well as compensatory hyperactivity in frontal regions.Significance: These findings provide insights into MDD working memory deficits, indicating that depressed individuals dedicate greater levels of cortical processing and cognitive resources to achieve comparable workig memory performance to controls.

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Maintaining fixation does not increase demands on working memory relative to free viewing

PeerJ ◽

10.7717/peerj.6839 ◽

2019 ◽

Vol 7 ◽

pp. e6839 ◽

Cited By ~ 6

Author(s):

Michael J. Armson ◽

Jennifer D. Ryan ◽

Brian Levine

Keyword(s):

Working Memory ◽

Eye Movements ◽

Response Times ◽

Memory Load ◽

Memory Performance ◽

Memory Task ◽

Oculomotor System ◽

Finger Tapping ◽

Long Term Memory ◽

Free Viewing

The comparison of memory performance during free and fixed viewing conditions has been used to demonstrate the involvement of eye movements in memory encoding and retrieval, with stronger effects at encoding than retrieval. Relative to conditions of free viewing, participants generally show reduced memory performance following sustained fixation, suggesting that unrestricted eye movements benefit memory. However, the cognitive basis of the memory reduction during fixed viewing is uncertain, with possible mechanisms including disruption of visual-mnemonic and/or imagery processes with sustained fixation, or greater working memory demands required for fixed relative to free viewing. To investigate one possible mechanism for this reduction, we had participants perform a working memory task—an auditory n-back task—during free and fixed viewing, as well as a repetitive finger tapping condition, included to isolate the effects of motor interference independent of the oculomotor system. As expected, finger tapping significantly interfered with n-back performance relative to free viewing, as indexed by a decrease in accuracy and increase in response times. By contrast, there was no evidence that fixed viewing interfered with n-back performance relative to free viewing. Our findings failed to support a hypothesis of increased working memory load during fixation. They are consistent with the notion that fixation disrupts long-term memory performance through interference with visual processes.

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Working Memory Depletion Affects Intertemporal Choice Among Internet Addicts and Healthy Controls

Frontiers in Psychology ◽

10.3389/fpsyg.2021.675059 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hongxia Li

Keyword(s):

Working Memory ◽

Delay Discounting ◽

Intertemporal Choice ◽

Response Times ◽

Memory Task ◽

Reaction Times ◽

Self Report ◽

The Internet ◽

Control Group ◽

Healthy Controls

Addiction to the Internet has emerged as a new kind of addictive behavior. Although previous studies have revealed that impairments in working memory led to suboptimal decision making (e.g., a greater willingness to choose smaller, more immediate rewards), little is known about how working memory affects intertemporal choice in Internet addicts and normal users. Thus, this study’s aim was to investigate the effect of working memory task on intertemporal choice in 33 participants addicted to internet and 25 healthy controls. Participants were administered (a) a test for Internet Addiction, (b) a single delay discounting self-report questionnaire (c) a working memory task. Differences between the Internet addicts and the control group were observed in terms of delay discounting rates, reaction times, and in memory accuracy rates. We observed significantly higher delay discounting rates among individuals addicted to the Internet. Moreover, it was documented that reaction times follow the 4-level working memory condition were significantly longer than follow the 2-level condition, in both the Internet addicts and the control group. The current findings suggest that Internet addicts are more likely to make short-sighted decisions than normal Internet users. The higher the level of working memory, the more likely an individual is to choose the present smaller reward, thus making short-sighted decisions, and have longer response times.

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Network Structure During Encoding Predicts Working Memory Performance

10.1101/409615 ◽

2018 ◽

Cited By ~ 1

Author(s):

Anirudh Wodeyar ◽

Ramesh Srinivasan

Keyword(s):

Working Memory ◽

Graphical Model ◽

Structural Characteristics ◽

Brain Activity ◽

Memory Performance ◽

Memory Function ◽

Brain Networks ◽

Memory Task ◽

Functional Clustering ◽

Network Properties

ABSTRACTWorking memory operates through networks that integrate distributed modular brain activity. We characterize the structure of networks in different electroencephalographic frequency bands while individuals perform a working memory task. The objective was to identify network properties that support working memory function during the encoding, maintenance, and retrieval of memory. In each EEG frequency band, we estimated a complex-valued Gaussian graphical model to characterize the structure of brain networks using measures from graph theory. Critically, the structural characteristics of brain networks that facilitate performance are all established during encoding, suggesting that they reflect the effect of attention on the quality of the representation in working memory. Segregation of networks in the alpha and beta bands during encoding increased with accuracy. In the theta band, greater integration of functional clusters involving the temporal lobe with other cortical areas predicted faster response time, starting in the encoding interval and persisting throughout the task, indicating that functional clustering facilitates rapid memory manipulation.

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History of Alcohol Consumption and HIV Status Related to Functional Connectivity Differences in the Brain During Working Memory Performance

Current HIV Research ◽

10.2174/1570162x18666200217100123 ◽

2020 ◽

Vol 18 (3) ◽

pp. 181-193 ◽

Cited By ~ 1

Author(s):

Vaughn E. Bryant ◽

Joseph M. Gullett ◽

Eric C. Porges ◽

Robert L. Cook ◽

Kendall J. Bryant ◽

...

Keyword(s):

Working Memory ◽

Functional Connectivity ◽

Alcohol Consumption ◽

Memory Performance ◽

Memory Function ◽

Brain Networks ◽

Memory Task ◽

Hiv Positive ◽

Hiv Status ◽

Using Data

Background: Poorer working memory function has previously been associated with alcohol misuse, Human Immunodeficiency Virus (HIV) positive status, and risky behavior. Poorer working memory performance relates to alterations in specific brain networks. Objective: The current study examined if there was a relationship between brain networks involved in working memory and reported level of alcohol consumption during an individual’s period of heaviest use. Furthermore, we examined whether HIV status and the interaction between HIV and alcohol consumption was associated with differences in these brain networks. Methods: Fifty adults, 26 of whom were HIV positive, engaged in an n-back working memory task (0-back and 2-back trials) administered in a magnetic resonance imaging (MRI) scanner. The Kreek- McHugh-Schluger-Kellogg (KMSK) scale of alcohol consumption was used to characterize an individual’s period of heaviest use and correlates well with their risk for alcohol dependence. Connectivity analyses were conducted using data collected during n-back task. Results: Functional connectivity differences associated with greater alcohol consumption included negative connectivity, primarily from parietal attention networks to frontal networks. Greater alcohol consumption was also associated with positive connectivity from working memory nodes to the precuneus and paracingulate. HIV positive status was associated with more nodes of negative functional connectivity relative to alcohol consumption history alone, particularly in the frontoparietal networks. The HIV positive individuals with heavier drinking history related to negative fronto-parietal connectivity, along with positive connectivity from working memory nodes to mesolimbic regions. Conclusion: Findings allow for a better understanding of brain networks affected by HIV and alcohol and may provide avenues for interventions.

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Mindfulness Training as Cognitive Training in High-Demand Cohorts: An Initial Study in Elite Military Servicemembers

10.31231/osf.io/5hzy7 ◽

2018 ◽

Author(s):

Anthony Paul Zanesco ◽

Ekaterina Denkova ◽

Scott L. Rogers ◽

William K. MacNulty ◽

Amishi P. Jha

Keyword(s):

Working Memory ◽

Cognitive Training ◽

Short Form ◽

Memory Performance ◽

Memory Task ◽

Selection Criterion ◽

Initial Study ◽

Mindfulness Training ◽

Training Tool ◽

Cognitive Failures

Cognitive ability is a key selection criterion for entry into many elite professions. Herein, we investigate whether mindfulness training (MT) can enhance cognitive performance in elite military forces. The cognitive effects of a short-form 8-hour MT program contextualized for military cohorts, referred to as Mindfulness-Based Attention Training (MBAT), were assessed. Servicemembers received either a 2-week (n = 40) or 4-week (n = 36) version of MBAT, or no training (NTC, n = 44). Sustained attention and working memory task performance along with self-reported cognitive failures were assessed at study onset (T1) and 8-weeks later (T2). In contrast to both the NTC and 2-week MT groups, the 4-week MT group significantly improved over time on attention and working memory outcome measures. Among the 4-week more so than the 2-week MBAT participants, working memory performance improvements were correlated with their amount of out-of-class MT practice. In addition to these group-wise effects, all participants receiving MBAT decreased in their self-reported cognitive failures from T1 to T2. Importantly, none of these improvements were related to self-reported task motivation. Together, these results suggest that short-form MT, when delivered over a 4-week delivery schedule, may be an effective cognitive training tool in elite military cohorts.

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Experiential and Strategic Emotional Intelligence Are Implicated When Inhibiting Affective and Non-Affective Distractors: Findings from Three Emotional Flanker N-Back Tasks

Journal of Intelligence ◽

10.3390/jintelligence9010012 ◽

2021 ◽

Vol 9 (1) ◽

pp. 12

Author(s):

Ming D. Lim ◽

Damian P. Birney

Keyword(s):

Working Memory ◽

Emotional Intelligence ◽

Experimental Evidence ◽

Cognitive Processes ◽

Response Times ◽

Memory Task ◽

Low Load ◽

Affective Information ◽

Accuracy Rates

Emotional intelligence (EI) refers to a set of competencies to process, understand, and reason with affective information. Recent studies suggest ability measures of experiential and strategic EI differentially predict performance on non-emotional and emotionally laden tasks. To explore cognitive processes underlying these abilities further, we varied the affective context of a traditional letter-based n-back working-memory task. In study 1, participants completed 0-, 2-, and 3-back tasks with flanking distractors that were either emotional (fearful or happy faces) or non-emotional (shapes or letters stimuli). Strategic EI, but not experiential EI, significantly influenced participants’ accuracy across all n-back levels, irrespective of flanker type. In Study 2, participants completed 1-, 2-, and 3-back levels. Experiential EI was positively associated with response times for emotional flankers at the 1-back level but not other levels or flanker types, suggesting those higher in experiential EI reacted slower on low-load trials with affective context. In Study 3, flankers were asynchronously presented either 300 ms or 1000 ms before probes. Results mirrored Study 1 for accuracy rates and Study 2 for response times. Our findings (a) provide experimental evidence for the distinctness of experiential and strategic EI and (b) suggest that each are related to different aspects of cognitive processes underlying working memory.

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Working Memory Performance under a Negative Affect Is More Susceptible to Higher Cognitive Workloads with Different Neural Haemodynamic Correlates

Brain Sciences ◽

10.3390/brainsci11070935 ◽

2021 ◽

Vol 11 (7) ◽

pp. 935

Author(s):

Ying Xing Feng ◽

Masashi Kiguchi ◽

Wei Chun Ung ◽

Sarat Chandra Dass ◽

Ahmad Fadzil Mohd Hani ◽

...

Keyword(s):

Working Memory ◽

Task Performance ◽

Memory Performance ◽

Affective State ◽

Memory Task ◽

Interactive Effects ◽

Functional Near Infrared Spectroscopy ◽

Affective Factors ◽

Related Stress ◽

Haemodynamic Activity

The effect of stress on task performance is complex, too much or too little stress negatively affects performance and there exists an optimal level of stress to drive optimal performance. Task difficulty and external affective factors are distinct stressors that impact cognitive performance. Neuroimaging studies showed that mood affects working memory performance and the correlates are changes in haemodynamic activity in the prefrontal cortex (PFC). We investigate the interactive effects of affective states and working memory load (WML) on working memory task performance and haemodynamic activity using functional near-infrared spectroscopy (fNIRS) neuroimaging on the PFC of healthy participants. We seek to understand if haemodynamic responses could tell apart workload-related stress from situational stress arising from external affective distraction. We found that the haemodynamic changes towards affective stressor- and workload-related stress were more dominant in the medial and lateral PFC, respectively. Our study reveals distinct affective state-dependent modulations of haemodynamic activity with increasing WML in n-back tasks, which correlate with decreasing performance. The influence of a negative effect on performance is greater at higher WML, and haemodynamic activity showed evident changes in temporal, and both spatial and strength of activation differently with WML.

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Does Strategic Memory Training Improve the Working Memory Performance of Younger and Older Adults?

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169.54.4.311 ◽

2007 ◽

Vol 54 (4) ◽

pp. 311-320 ◽

Cited By ~ 66

Author(s):

Barbara Carretti ◽

Erika Borella ◽

Rossana De Beni

Keyword(s):

Older Adults ◽

Working Memory ◽

Memory Performance ◽

Memory Task ◽

Memory Training ◽

Control Groups ◽

Improved Performance ◽

Strategic Training ◽

Strategic Memory ◽

Experimental Group

Abstract. The paper examines the effect of strategic training on the performance of younger and older adults in an immediate list-recall and a working memory task. The experimental groups of younger and older adults received three sessions of memory training, teaching the use of mental images to improve the memorization of word lists. In contrast, the control groups were not instructed to use any particular strategy, but they were requested to carry out the memory exercises. The results showed that strategic training improved performance of both the younger and older experimental groups in the immediate list recall and in the working memory task. Of particular interest, the improvement in working memory performance of the older experimental group was comparable to that of the younger experimental group.

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Memory-Related Frontal Brainwaves Predict Transition to Mild Cognitive Impairment in Healthy Older Individuals Five Years Before Diagnosis

Journal of Alzheimer s Disease ◽

10.3233/jad-200931 ◽

2020 ◽

pp. 1-11

Author(s):

Yang Jiang ◽

Juan Li ◽

Frederick A. Schmitt ◽

Gregory A. Jicha ◽

Nancy B. Munro ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Memory Performance ◽

Memory Task ◽

Cognitive Status ◽

Older Individuals ◽

Increased Risk ◽

Differentiation Pattern

Background: Early prognosis of high-risk older adults for amnestic mild cognitive impairment (aMCI), using noninvasive and sensitive neuromarkers, is key for early prevention of Alzheimer’s disease. We have developed individualized measures in electrophysiological brain signals during working memory that distinguish patients with aMCI from age-matched cognitively intact older individuals. Objective: Here we test longitudinally the prognosis of the baseline neuromarkers for aMCI risk. We hypothesized that the older individuals diagnosed with incident aMCI already have aMCI-like brain signatures years before diagnosis. Methods: Electroencephalogram (EEG) and memory performance were recorded during a working memory task at baseline. The individualized baseline neuromarkers, annual cognitive status, and longitudinal changes in memory recall scores up to 10 years were analyzed. Results: Seven of the 19 cognitively normal older adults were diagnosed with incident aMCI for a median 5.2 years later. The seven converters’ frontal brainwaves were statistically identical to those patients with diagnosed aMCI (n = 14) at baseline. Importantly, the converters’ baseline memory-related brainwaves (reduced mean frontal responses to memory targets) were significantly different from those who remained normal. Furthermore, differentiation pattern of left frontal memory-related responses (targets versus nontargets) was associated with an increased risk hazard of aMCI (HR = 1.47, 95% CI 1.03, 2.08). Conclusion: The memory-related neuromarkers detect MCI-like brain signatures about five years before diagnosis. The individualized frontal neuromarkers index increased MCI risk at baseline. These noninvasive neuromarkers during our Bluegrass memory task have great potential to be used repeatedly for individualized prognosis of MCI risk and progression before clinical diagnosis.

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Negative Effects of Embodiment in a Visuo-Spatial Working Memory Task in Children, Young Adults, and Older Adults

Frontiers in Psychology ◽

10.3389/fpsyg.2021.688174 ◽

2021 ◽

Vol 12 ◽

Author(s):

Gianluca Amico ◽

Sabine Schaefer

Keyword(s):

Older Adults ◽

Working Memory ◽

Young Adults ◽

Spatial Information ◽

Spatial Working Memory ◽

Cognitive Task ◽

Memory Performance ◽

Age Groups ◽

Memory Task ◽

Negative Effects

Studies examining the effect of embodied cognition have shown that linking one’s body movements to a cognitive task can enhance performance. The current study investigated whether concurrent walking while encoding or recalling spatial information improves working memory performance, and whether 10-year-old children, young adults, or older adults (Mage = 72 years) are affected differently by embodiment. The goal of the Spatial Memory Task was to encode and recall sequences of increasing length by reproducing positions of target fields in the correct order. The nine targets were positioned in a random configuration on a large square carpet (2.5 m × 2.5 m). During encoding and recall, participants either did not move, or they walked into the target fields. In a within-subjects design, all possible combinations of encoding and recall conditions were tested in counterbalanced order. Contrary to our predictions, moving particularly impaired encoding, but also recall. These negative effects were present in all age groups, but older adults’ memory was hampered even more strongly by walking during encoding and recall. Our results indicate that embodiment may not help people to memorize spatial information, but can create a dual-task situation instead.

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