Complexity measures reveal age-dependent changes in electroencephalogram during working memory task.

The alterations in electroencephalogram (EEG) signals are the complex outputs of functional factors, such as normal physiological aging, pathological process, which results in further cognitive decline. It is not clear that when brain aging initiates, but elderly people are vulnerable to be incipient of neurodegenerative diseases such as Alzheimer's disease. The EEG signals were recorded from 20 healthy middle age and 20 healthy elderly subjects while performing a working memory task. Higuchi's fractal dimension (HFD), Katz's fractal dimension (KFD), sample entropy and three Hjorth parameters were extracted to analyse the complexity of EEG signals. Four machine learning classifiers, multilayer perceptron (MLP), support vector machine (SVM), K-nearest neighbour (KNN), and logistic model tree (LMT) were employed to distinguish the EEG signals of middle age and elderly age groups. HFD, KFD and Hjorth complexity were found significantly correlated with age. MLP achieved the highest overall accuracy of 93.75%. For posterior region, the maximum accuracy of 92.50% was achieved using MLP. Since fractal dimension associated with the complexity of EEG signals, HFD, KFD and Hjorth complexity demonstrated the decreased complexity from middle age to elderly groups. The complexity features appear to be more appropriate indicators of monitoring EEG signal complexity in healthy aging.

Alterations in brain functional connectivity in patients with mild cognitive impairment: A systematic review and meta-analysis of functional near-infrared spectroscopy studies.

Emerging evidences suggest that cognitive deficits in individuals with mild cognitive impairment (MCI) are associated with disruptions in brain functional connectivity (FC). This systematic review and meta-analysis aimed to comprehensively evaluate alterations in FC between MCI individuals and healthy control (HC) using functional near-infrared spectroscopy (fNIRS). Thirteen studies were included in qualitative analysis, with two studies synthesized for quantitative meta-analysis. Overall, MCI patients exhibited reduced resting-state FC, predominantly in the prefrontal, parietal, and occipital cortex. Meta-analysis of two studies revealed a significant reduction in resting-state FC from the right prefrontal to right occipital cortex (standardized mean difference [SMD] = -.56; p < .001), left prefrontal to left occipital cortex (SMD = -.68; p < .001), and right prefrontal to left occipital cortex (SMD = -.53; p < .001) in MCI patients compared to HC. During naming animal-walking task, MCI patients exhibited enhanced FC in the prefrontal, motor, and occipital cortex, whereas a decrease in FC was observed in the right prefrontal to left prefrontal cortex during calculating-walking task. In working memory tasks, MCI predominantly showed increased FC in the medial and left prefrontal cortex. However, a decreased in prefrontal FC and a shifted in distribution from the left to the right prefrontal cortex were noted in MCI patients during a verbal frequency task. In conclusion, fNIRS effectively identified abnormalities in FC between MCI and HC, indicating disrupted FC as potential markers for the early detection of MCI. Future studies should investigate the use of task- and region-specific FC alterations as a sensitive biomarker for MCI.

Characteristics of event-related potential and frequency on working memory of post-stroke aphasia / 中国康复理论与实践

Objective To explore the task-state electroencephalogram(EEG)characteristics of working memory in patients with post-stroke aphasia(PSA). Methods From September,2020 to February,2021,a total of eight patients with PSA(PSA group)and eight healthy adults(HC group)were recruited to collect EEG and memory scale data.The EEG data of working memory task-states were used to analyze the characteristics of the EEG frequency band indicators in time domain event-related potentials(ERP)and frequency;and the correlation with the items in the memory scale. Results Finally,five patients and five controls were included.N1 and P2 components were induced in the frontal area,and P300 components were induced in the parieto-occipital area.Compared with HC group,the activation of N1 and P2 increased in central prefrontal region,while the activity of P300 decreased in the right parieto-occipital re-gion in PSA group(|t|>2.193,P<0.05).The energy of theta band decreased in the right prefrontal region and the central parieto-occipital region,the energy of alpha1 band decreased in the left parieto-occipital region,and the energy of gamma band increased in the left central region(t>2.398,P<0.05).The energy of gamma band correlated with immediate recall(r = 0.914,P = 0.030)and correct recognition(r = 0.931,P = 0.022)of Auditory Verbal Learning Test,and inverting(r = 0.924,P = 0.025)and anterograde(r = 0.889,P = 0.044)of Digit Span Test. Conclusion Visual working memory task can activate the compensatory processing activity of memory related brain re-gions after PSA,which can be used as an objective indication for the evaluation of PSA working memory related research.There is close relationship between language impairment and working memory.

Evaluation of physiological responses to mental workload in n-back and arithmetic tasks.

Working memory tasks, such as n-back and arithmetic tasks, are frequently used in studying mental workload. The present study investigated and compared the sensitivity of several physiological measures at three levels of difficulty of n-back and arithmetic tasks. The results showed significant differences in fixation duration and pupil diameter among three task difficulty levels for both n-back and arithmetic tasks. Pupil diameters increase with increasing mental workload, whereas fixation duration decreases. Blink duration and heart rate (HR) were significantly increased as task difficulty increased in the n-back task, while root mean square of successive differences (RMSSD) and standard deviation of R-R intervals (SDNN) were significantly decreased in the arithmetic task. On the other hand, blink rate and Galvanic Skin Response (GSR) were not sensitive enough to assess the differences in task difficulty for both tasks. All significant physiological measures yielded significant differences between low and high task difficulty except for SDNN.Practitioner summary: This study aimed to assess the sensitivity levels of several physiological measures of mental workload in n-back and arithmetic tasks. It showed that pupil diameter was the most sensitive in both tasks. This study also found that most physiological indices are sensitive to an extreme change in task difficulty levels.

Relationship Between Left-Right Dominancy of Prefrontal Cortex Activity and Heart Rate During Rest and Task Periods: An fNIRS Study.

BackgroundFunctional near-infrared spectroscopy (fNIRS) studies demonstrated that regulation of stress response of the autonomic nervous system is mediated by the left-right asymmetry of prefrontal cortex (PFC) activity. However, it is not yet clear whether PFC regulation of stress response is functioning only when the subject was under stress or even at rest without stress. In addition, the temporal responsivity of PFC regulation of stress response is not known.AimThis study aims to investigate the relationship between the left-right asymmetry of PFC activity and heart rate during both resting state and stressful state while performing a working memory task.ApproachTwenty-nine subjects were recruited to rest and conduct 2-back task, during which fNIRS and ECG were measured simultaneously.ResultsWe found weak correlation (r = 0.28, p = 0.137) between laterality index (LI) and heart rate in the task session, but no correlation in rest sessions at a group level. Moreover, weak but significant correlation was found only in the task session for all analysis intervals ranged from 2 s to 1 min.ConclusionIt is suggested that regulation of stress responses was mediated by the left-right asymmetry of PFC activity only when the subject was under stress stimuli and embody stress response did not affect PFC in reverse. This regulation can be observed at an analysis interval of no less than 2 s.

Aging decreases the precision of visual working memory.

OBJECTIVES: As individuals age, cognitive abilities such as working memory (WM), decline. In the current study, we investigated the effect of age on WM, and elucidated sources of errors. METHOD: A total of 102 healthy individuals, aged 18 to 71, participated in this research. We designed and administered a face-based visual WM task, collecting responses via a graded scale in a delayed match-to-sample reproduction task. RESULTS: The error of participants increased significantly as they aged. Our analysis revealed a significant age-related rise in the standard deviation of error distribution. However, there was no significant change in uniform probability with age. CONCLUSION: We found that WM performance declines through the lifespan. Investigating the sources of error, we found that the precision of WM decreased monotonously with age. The results also indicated that the probability of guessing the response as a measure of random response is not affected by age.

Latent brain state dynamics and cognitive flexibility in older adults.

Cognitive impairment in older adults is a rapidly growing public health concern as the elderly population dramatically grows worldwide. While it is generally assumed that cognitive deficits in older adults are associated with reduced brain flexibility, quantitative evidence has been lacking. Here, we investigate brain flexibility in healthy older adults (ages 60-85) using a novel Bayesian switching dynamical system algorithm and ultrafast temporal resolution (TR = 490 ms) whole-brain fMRI data during performance of a Sternberg working memory task. We identify latent brain states and characterize their dynamic temporal properties, including state transitions, associated with encoding, maintenance, and retrieval. Crucially, we demonstrate that brain inflexibility is associated with slower and more fragmented transitions between latent brain states, and that brain inflexibility mediates the relation between age and cognitive inflexibility. Our study provides a novel neurocomputational framework for investigating latent dynamic circuit processes underlying brain flexibility and cognition in the context of aging.

Lower functional connectivity of white matter during rest and working memory tasks is associated with cognitive impairments in schizophrenia.

BACKGROUND: Schizophrenia can be understood as a disturbance of functional connections within brain networks. However, functional alterations that involve white matter (WM) specifically, or their cognitive correlates, have seldomly been investigated, especially during tasks. METHODS: Resting state and task fMRI images were acquired on 84 patients and 67 controls. Functional connectivities (FC) between 46 WM bundles and 82 cortical regions were compared between the groups under two conditions (i.e., resting state and during working memory retention period). The FC density of each WM bundle was then compared between groups. Associations of FC with cognitive scores were evaluated. RESULTS: FC measures were lower in schizophrenia relative to controls for external capsule, cingulum (cingulate and hippocampus), uncinate fasciculus, as well as corpus callosum (genu and body) under the rest or the task condition, and were higher in the posterior corona radiata and posterior thalamic radiation during the task condition. FC for specific WM bundles was correlated with cognitive performance assessed by working memory and processing speed metrics. CONCLUSIONS: The findings suggest that the functional abnormalities in patients' WM are heterogeneous, possibly reflecting several underlying mechanisms such as structural damage, functional compensation and excessive effort on task, and that WM FC disruption may contribute to the impairments of working memory and processing speed. This is the first report on WM FC abnormalities in schizophrenia relative to controls and their cognitive associates during both rest and task and highlights the need to consider WM functions as components of brain functional networks in schizophrenia.

Identification of Breathing Patterns through EEG Signal Analysis Using Machine Learning.

This study was to investigate the changes in brain function due to lack of oxygen (O2) caused by mouth breathing, and to suggest a method to alleviate the side effects of mouth breathing on brain function through an additional O2 supply. For this purpose, we classified the breathing patterns according to EEG signals using a machine learning technique and proposed a method to reduce the side effects of mouth breathing on brain function. Twenty subjects participated in this study, and each subject performed three different breathings: nose and mouth breathing and mouth breathing with O2 supply during a working memory task. The results showed that nose breathing guarantees normal O2 supply to the brain, but mouth breathing interrupts the O2 supply to the brain. Therefore, this comparative study of EEG signals using machine learning showed that one of the most important elements distinguishing the effects of mouth and nose breathing on brain function was the difference in O2 supply. These findings have important implications for the workplace environment, suggesting that special care is required for employees who work long hours in confined spaces such as public transport, and that a sufficient O2 supply is needed in the workplace for working efficiency.

An increase in the deoxygenated hemoglobin concentration induced by a working memory task during the refractory period in the hemodynamic response in the human cerebral cortex.

In activated brain regions, the deoxygenated hemoglobin (deoxy-Hb) concentration decreases despite an increase in oxygen consumption. This is attributed to the fact that the cerebral blood flow (CBF) induced by neuronal activation exceeds the accompanying increase in the cerebral metabolic rate of oxygen (CMRO2). The discrepancy between large CBF and disproportionately small CMRO2 responses provides the basis for detecting the hemodynamic correlates of neuronal activities by functional magnetic resonance imaging (fMRI). However, this implies that if the supply of oxygen is made smaller than the oxygen consumed by the suppression of stimulus-induced CBF, the polarity of signals would be reversed. We used near-infrared spectroscopy (NIRS) to search for a condition wherein a marked decrease in the stimulus-evoked oxygenated Hb (oxy-Hb) concentration change was accompanied by an increase in the deoxy-Hb concentration in the human brain. We found that when a specific brain region was activated by two working memory (WM) task blocks in rapid succession, the local change in the deoxy-Hb concentration evoked by the second task block was reversed to an increase due to the refractory effect in the hemodynamic response. The result suggests that the polarity of the blood oxygenation level-dependent (BOLD) signal could change during repetitive neuronal activation, and thus caution must be taken in the interpretation of the BOLD signal under such situations.

Deactivation of default-mode network and early suppression of decision-making areas during retrieval period by high-arousing emotions improves performance in verbal working memory task.

Emotions affect many aspects of cognition (attention, decision-making, problem solving, conflict resolution, task switching, social cognition, etc.), but the cortical areas or networks through which these effects are achieved are still debatable. In the present study, the effect of emotion on cognition was studied in healthy young individuals (n = 56). Emotions were induced using high-arousing negative, positive, and low-arousing neutral pictures from the International Affective Picture System (IAPS). Sternberg's verbal working memory task was administered at baseline and after each emotion exposure, while high-density EEG was recorded. Cortical sources were calculated using sLORETA in the 500-ms window (for every 100 ms bin) before the response and were compared with baseline. Though the number of correct responses were comparable, reaction times after emotion exposure reduced significantly. Source analysis revealed significant deactivation of default mode network (DMN) areas as well as early deactivation of decision-making areas during Sternberg's task performed after both the negative and positive emotions. This early deactivation, much before the response was made, when compared with baseline suggests that tasks performed under high-arousing emotional states may help in making decisions earlier or faster. We conclude that the exposure to high-arousing emotional stimuli improves verbal working memory by helping in directing the attentional resources toward the task, thus decreasing the decision-making time and further suppressing the DMN areas.

Comparison of prefrontal hemodynamic responses and cognitive deficits between adult patients with autism spectrum disorder and schizophrenia.

Autism spectrum disorder (ASD) and schizophrenia share many phenotypic characteristics, but their association with prefrontal function have not been directly compared. The aim of this study is to compare cognitive profiles and their association with the prefrontal function between the two groups. We explored prefrontal dysfunction among adult individuals with ASD (n = 32), schizophrenia (n = 87), and healthy controls (HCs; n = 50). We assessed cognitive function in all participants using the Brief Assessment of Cognition in Schizophrenia (BACS). The BACS data of patients with schizophrenia were entered into hierarchical cluster analyses to assign subjects to a specific subgroup based on individual profiles. Using near-infrared spectroscopy, we measured hemodynamic responses in the fronto-temporal regions during a working memory task. Among the patients with schizophrenia, we defined 4 neurocognitive subgroups, including a global impairment, a mild impairment, and 2 selective impairment groups. Compared to the HCs, the ASD and schizophrenia groups had much weaker hemodynamic responses in the left DLPFC, left frontopolar cortex (FPC), and left inferior frontal gyrus. The ASD group showed a similar level of cognitive impairment with the mild level subgroup of schizophrenia. Additionally, the two groups shared reduced activity in the left DLPFC and left FPC during the task compared to HCs. Moreover, the BACS composite scores correlated positively with hemodynamic responses in a broad area involving fronto-temporal regions in the total patient sample. This research indicates considerable similarity in the left PFC dysfunction and its association with cognitive deficits between the disorders. These findings may guide future studies that investigate pathophysiological similarities between ASD and schizophrenia.

EEG dipole source localization with information criteria for multiple particle filters.

Electroencephalography (EEG) is a non-invasive brain imaging technique that describes neural electrical activation with good temporal resolution. Source localization is required for clinical and functional interpretations of EEG signals, and most commonly is achieved via the dipole model; however, the number of dipoles in the brain should be determined for a reasonably accurate interpretation. In this paper, we propose a dipole source localization (DSL) method that adaptively estimates the dipole number by using a novel information criterion. Since the particle filtering process is nonparametric, it is not clear whether conventional information criteria such as Akaike's information criterion (AIC) and Bayesian information criterion (BIC) can be applied. In the proposed method, multiple particle filters run in parallel, each of which respectively estimates the dipole locations and moments, with the assumption that the dipole number is known and fixed; at every time step, the most predictive particle filter is selected by using an information criterion tailored for particle filters. We tested the proposed information criterion first through experiments on artificial datasets; these experiments supported the hypothesis that the proposed information criterion would outperform both AIC and BIC. We then analyzed real human EEG datasets collected during an auditory short-term memory task using the proposed method. We found that the alpha-band dipoles were localized to the right and left auditory areas during the auditory short-term memory task, which is consistent with previous physiological findings. These analyses suggest the proposed information criterion can work well in both model and real-world situations.

Reduced Functional Connectivity in Adults with Persistent Post-Concussion Symptoms: A Functional Near-Infrared Spectroscopy Study.

Concussion, or mild traumatic brain injury (mTBI), accounts for ∼80% of all TBIs across North America. The majority of mTBI patients recover within days to weeks; however, 14-36% of the time, acute mTBI symptoms persist for months or even years and develop into persistent post-concussion symptoms (PPCS). There is a need to find biomarkers in patients with PPCS, to improve prognostic ability and to provide insight into the pathophysiology underlying chronic symptoms. Recent research has pointed toward impaired network integrity and cortical communication as a biomarker. In this study we investigated functional near-infrared spectroscopy (fNIRS) as a technique to assess cortical communication deficits in adults with PPCS. Specifically, we aimed to identify cortical communication patterns in prefrontal and motor areas during rest and task, in adult patients with persistent symptoms. We found that (1) the PPCS group showed reduced connectivity compared with healthy controls, (2) increased symptom severity correlated with reduced coherence, and (3) connectivity differences were best distinguishable during task and in particular during the working memory task (n-back task) in the right and left dorsolateral prefrontal cortex (DLPFC). These data show that reduced brain communication may be associated with the pathophysiology of mTBI and that fNIRS, with a relatively simple acquisition paradigm, may provide a useful biomarker of this injury.

Analyze the beta waves of electroencephalogram signals from young musicians and non-musicians in major scale working memory task.

Electroencephalograms can record wave variations in any brain activity. Beta waves are produced when an external stimulus induces logical thinking, computation, and reasoning during consciousness. This work uses the beta wave of major scale working memory N-back tasks to analyze the differences between young musicians and non-musicians. After the feature analysis uses signal filtering, Hilbert-Huang transformation, and feature extraction methods to identify differences, k-means clustering algorithm are used to group them into different clusters. The results of feature analysis showed that beta waves significantly differ between young musicians and non-musicians from the low memory load of working memory task.

Playing the computer game Tetris prior to viewing traumatic film material and subsequent intrusive memories: Examining proactive interference.

BACKGROUND AND OBJECTIVES: Visuospatial working memory (WM) tasks performed concurrently or after an experimental trauma (traumatic film viewing) have been shown to reduce subsequent intrusive memories (concurrent or retroactive interference, respectively). This effect is thought to arise because, during the time window of memory consolidation, the film memory is labile and vulnerable to interference by the WM task. However, it is not known whether tasks before an experimental trauma (i.e. proactive interference) would also be effective. Therefore, we tested if a visuospatial WM task given before a traumatic film reduced intrusions. Findings are relevant to the development of preventative strategies to reduce intrusive memories of trauma for groups who are routinely exposed to trauma (e.g. emergency services personnel) and for whom tasks prior to trauma exposure might be beneficial. METHODS: Participants were randomly assigned to 1 of 2 conditions. In the Tetris condition (n = 28), participants engaged in the computer game for 11 min immediately before viewing a 12-min traumatic film, whereas those in the Control condition (n = 28) had no task during this period. Intrusive memory frequency was assessed using an intrusion diary over 1-week and an Intrusion Provocation Task at 1-week follow-up. Recognition memory for the film was also assessed at 1-week. RESULTS: Compared to the Control condition, participants in the Tetris condition did not report statistically significant difference in intrusive memories of the trauma film on either measure. There was also no statistically significant difference in recognition memory scores between conditions. LIMITATIONS: The study used an experimental trauma paradigm and findings may not be generalizable to a clinical population. CONCLUSIONS: Compared to control, playing Tetris before viewing a trauma film did not lead to a statistically significant reduction in the frequency of later intrusive memories of the film. It is unlikely that proactive interference, at least with this task, effectively influences intrusive memory development. WM tasks administered during or after trauma stimuli, rather than proactively, may be a better focus for intrusive memory amelioration.

The association between cognitive deficits and prefrontal hemodynamic responses during performance of working memory task in patients with schizophrenia.

Schizophrenia-associated cognitive deficits are resistant to treatment and thus pose a lifelong burden. The Brief Assessment of Cognition in Schizophrenia (BACS) provides reliable and valid assessments across cognitive domains. However, because the prefrontal functional abnormalities specifically associated with the level of cognitive deficits in schizophrenia have not been examined, we explored this relationship. Patients with schizophrenia (N=87) and matched healthy controls (N=50) participated in the study. Using near-infrared spectroscopy (NIRS), we measured the hemodynamic responses in the prefrontal and superior temporal cortical surface areas during a working memory task. Correlation analyses revealed a relationship between the hemodynamics and the BACS composite and domain scores. Hemodynamic responses of the left dorsolateral prefrontal cortex (DLPFC) and left frontopolar cortex (FPC) in the higher-level-of-cognitive-function schizophrenia group were weaker than the responses of the controls but similar to those of the lower-level-of-cognitive-function schizophrenia group. However, hemodynamic responses in the right DLPFC, bilateral ventrolateral PFC (VLPFC), and right temporal regions decreased with increasing cognitive deficits. In addition, the hemodynamic response correlated positively with the level of cognitive function (BACS composite scores) in the right DLPFC, bilateral VLPFC, right FPC, and bilateral temporal regions in schizophrenia. The correlation was driven by all BACS domains. Our results suggest that the linked functional deficits in the right DLPFC, bilateral VLPFC, right FPC, and bilateral temporal regions may be related to BACS-measured cognitive impairments in schizophrenia and show that linking the neurocognitive deficits and brain abnormalities can increase our understanding of schizophrenia pathophysiology.

Effect of Experimental Thyrotoxicosis on Brain Gray Matter: A Voxel-Based Morphometry Study.

BACKGROUND: Hyper-as well hypothyroidism have an effect on behavior and brain function. Moreover, during development thyroid hormones influence brain structure. OBJECTIVES: This study aimed to demonstrate an effect of experimentally induced hyperthyroidism on brain gray matter in healthy adult humans. METHODS: High-resolution 3D T1-weighted images were acquired in 29 healthy young subjects prior to as well as after receiving 250 µg of T4 per day for 8 weeks. Voxel-based morphometry analysis was performed using Statistical Parametric Mapping 8 (SPM8). RESULTS: Laboratory testing confirmed the induction of hyperthyroidism. In the hyperthyroid condition, gray matter volumes were increased in the right posterior cerebellum (lobule VI) and decreased in the bilateral visual cortex and anterior cerebellum (lobules I-IV) compared to the euthyroid condition. CONCLUSIONS: Our study provides evidence that short periods of hyperthyroidism induce distinct alterations in brain structures of cerebellar regions that have been associated with sensorimotor functions as well as working memory in the literature.

The effects of acute alcohol on psychomotor, set-shifting, and working memory performance in older men and women.

A limited number of publications have documented the effects of acute alcohol administration among older adults. Among these, only a few have investigated sex differences within this population. The current project examined the behavioral effects of acute low- and moderate-dose alcohol on 62 older (ages 55-70) male and female, healthy, light to moderate drinkers. Participants were randomly assigned to one of three dose conditions: placebo (peak breath alcohol concentration [BrAC] of 0 mg/dL), low (peak BrAC of 40 mg/dL), and moderate (peak BrAC of 65 mg/dL). Tasks assessed psychomotor, set-shifting, and working memory performance. Better set-shifting abilities were observed among women, whereas men demonstrated more efficient working memory, regardless of dose. The moderate-dose group did not significantly differ from the placebo group on any task. However, the low-dose group performed better than the moderate-dose group across measures of set shifting and working memory. Relative to the placebo group, the low-dose group exhibited better working memory, specifically for faces. Interestingly, there were no sex by dose interactions. These data suggest that, at least for our study's task demands, low and moderate doses of alcohol do not significantly hinder psychomotor, set-shifting, or working memory performance among older adults. In fact, low-dose alcohol may facilitate certain cognitive abilities. Furthermore, although sex differences in cognitive abilities were observed, these alcohol doses did not differentially affect men and women. Further investigation is necessary to better characterize the effects of sex and alcohol dose on cognition in older adults.

An EEG-based mental workload estimator trained on working memory task can work well under simulated multi-attribute task.

Mental workload (MW)-based adaptive system has been found to be an effective approach to enhance the performance of human-machine interaction and to avoid human error caused by overload. However, MW estimated from the spontaneously generated electroencephalogram (EEG) was found to be task-specific. In existing studies, EEG-based MW classifier can work well under the task used to train the classifier (within-task) but crash completely when used to classify MW of a task that is similar to but not included in the training data (cross-task). The possible causes have been considered to be the task-specific EEG patterns, the mismatched workload across tasks and the temporal effects. In this study, cross-task performance-based feature selection (FS) and regression model were tried to cope with these challenges, in order to make EEG-based MW estimator trained on working memory tasks work well under a complex simulated multi-attribute task (MAT). The results show that the performance of regression model trained on working memory task and tested on multi-attribute task with the feature subset picked-out were significantly improved (correlation coefficient (COR): 0.740 ± 0.147 and 0.598 ± 0.161 for FS data and validation data respectively) when compared to the performance in the same condition with all features (chance level). It can be inferred that there do exist some MW-related EEG features can be picked out and there are something in common between MW of a relatively simple task and a complex task. This study provides a promising approach to measure MW across tasks.