Mental Task Performance Research Articles

Comparison of mental fatigue using EEG signals and task performance in normal and slump posture adults during computer typing

ObjectivesSlump sitting at workstations has been focused on by clinicians and researchers nowadays; however, there is limited evidence to date that improper positioning affects the mental state. Accordingly, the main objective of this research was to examine the impact of slump posture on mental fatigue and task performance. MethodsA sample of 60 participants, 30 in each group including those with normal and slump postures were recruited to perform an hour of typing on the computer. Mental fatigue through EEG and task performances were considered as outcome measures and then were analyzed statistically in the first and last 3 min of typing. ResultsThe EEG showed a significant increasing trend in theta rhythm at different brain regions during 60 min of typing (P < 0.05). Besides, an interaction between time and posture was observed; it can mean the increasing trend of theta rhythm is different in normal and slump posture acquired sets (P < 0.05).Interestingly the speed of typing was found to be better (P < 0.05) in the normal posture group while no difference found between the groups in terms of errors (P > 0.05). ConclusionOur results showed poor posture can induce more mental fatigue during the given task, than the normal posture. These findings have provided evidence to indicate that in addition to the peripheral and biomechanical component, the assessment of the cortex as the central component should be considered in poor posture individuals. Besides, for any possible physical therapy rehabilitation protocol for the management of poor posture, the peripheral and central components should be focused. Trial registrationRegistered on the Iranian Registry of Clinical Trials on September 21, 2022, IRCT Identifier: IRCT20161026030516N2.

The Effects of Eye Illuminance Distribution in the Horizontal Field of View on Human Performance in a Home Paper-Based Learning Situation

Previous studies have focused on task/ambient illumination for visual effects and eye illumination for non-visual effects. In this context, eye illumination within the non-visual realm was defined as vertical non-visual eye illuminance. Considering the functional specificity of central vision and peripheral vision, this study aims to explore whether the distribution of eye illuminance in the horizontal field of view (FOV) affects human performance in home paper-based learning settings. In this study, a within-subject design was used to investigate the effects of eye illuminance distribution on mental perception, task performance, and physiological health while maintaining constant task illuminance and correlated color temperature (CCT). The findings revealed that eye illuminance and its distribution in the horizontal FOV had complex effects on visual fatigue, Landolt ring performance, heart rate variability, and luminous environment appraisal. A relatively optimal lighting configuration was suggested—Scene 4, which was characterized by an eye illuminance level in central FOV of 186 lx and an “m” shaped eye illuminance distribution pattern. This indicates the importance of considering eye illuminance distribution in the horizontal FOV, rather than solely focusing on vertical eye illuminance.

Electroencephalogram Functional Connectivity Analysis and Classification of Mental Arithmetic Working Memory Task

Analyzing brain activity during mental arithmetic tasks provides insight into psychological disorders such as ADHD, dyscalculia, and autism. While most research is conducted on the static functional connectivity of the brain while performing a cognitive task, the dynamic changes of the brain, which provide meaningful information for diagnosing individual differences in cognitive tasks, are often ignored. This paper aims to classify electroencephalogram (EEG) signals for rest vs. mental arithmetic task performance, using Bayesian functional connectivity features in the sensor space as inputs into a graph convolutional network. The subject-specific (intrasubject) classification performed on 36 subjects for rest vs. mental arithmetic task performance achieved the highest subject-specific classification accuracy of 98% and an average accuracy of 91% in the beta frequency band, outperforming state-of-the-art methods. In addition, statistical analysis confirms the consistency of Bayesian functional connectivity features compared to traditional functional connectivity features. Furthermore, the graph-theoretical analysis of functional connectivity networks reveals that good-performance subjects had higher global efficiency, betweenness centrality, and closeness centrality than bad-performance subjects. The ablation study on the classification of three cognitive states (subtraction, music, and memory) achieved a classification accuracy of 97%, and visual working memory (n-back task) achieved a classification accuracy of 94%, confirming the consistency and reliability of the proposed methodology.

Effects of green tea and roasted green tea on human responses

Our objective was to elucidate the effects of tea consumption on refreshment and stress reduction/recovery through examining the multiple associations among factors such as various physiological responses and task performance. Participants included 20 healthy young men who performed a mental arithmetic task while 11 physiological responses were measured. The experiments were conducted twice under different beverage consumption conditions on separate days. The mental arithmetic task was executed six times in 1 day; participants ingested hot water, green tea, or roasted green tea (hojicha) before each task. Several subjective assessments: subjective fatigue, stress, mental workload, and flow were evaluated after each task. The R–R intervals, heart rate variability spectral components, the Poincaré plot indices (SD1 and SD2) and plethysmogram amplitude tended to decrease during task periods compared to resting periods. Tissue blood volume/flow (TBV, TBF) and near-infrared spectroscopy responses (NIRS) were lower in the tea condition than in the hot water condition. By scrutinizing various indicators, we found that aromatic stimulation of Japanese tea beverages has the potential to induce positive effects, enhance mental task performance, promote refreshment, and alleviate feelings of fatigue. These positive effects were observed even in small quantities and within a short duration, mirroring responses observed in daily consumption.

Effects of Sampling Length and Overlap Ratio on EEG Mental Arithmetic Task Performance: A Comparative Study

Cognitive tasks have become quite popular in recent years. Understanding this sort of neurological research, its real-world applications, and how it may be improved in future studies are crucial. For this purpose, our study compares the classification accuracies for various segment lengths and overlap ratios for EEG recordings collected from 36 healthy volunteers during mental arithmetic tasks. EEG features are extracted from brain signals using the wavelet spectrum and the sample length and the overlap ratio of the sliding Windows are used as parameters. Feature selection was conducted using Correlation-Based and ReliefF feature selections. Subsequently, for classification results, Support Vector Machine, Random Forest, C4.5 Algorithm and k-Nearest Neighbor algorithms were employed, with the outcomes supported by the F1-score and Matthew's correlation coefficient. Therefore, the reliability of the obtained results has been ensured. In the comparisons obtained, the best average results for Accuracy, F1-score, and Matthew's correlation coefficient were found to be 0.990, 0.987, and 0.975 respectively, when applying the ReliefF feature selection method with the Support Vector Machine classifier.

The Effect of Background Music with Lyrics on Human Decision-making Performance of Mental Arithmetic Task

The Effect of Background Music with Lyrics on Human Decision-making Performance of Mental Arithmetic Task

Influence of automation level of human-machine system on operators’ mental load

The appropriate automation in armored vehicles is vital for the operational efficiency and personnel security of operators. In this study, fifty subjects conducted over-the-horizon strike and N-back tests at different automation levels based on a virtual simulation system for armored vehicles. Physiological signals and subjective assessments were recorded. The mental load and task performance of operators were related to different automation levels. Results suggested that the mental load decreased with the increase of automation levels. Apart from object destruction time, heart rate and standard deviation of NN intervals (SDNN), other indexes were all significantly affected by the automation level of subtasks (p ​< ​0.01). The NASA-TLX scores, object destruction time, response time of abnormal states, and reaction time in N-back tests decreased by at least 2.9 ​%, 8.2 ​%, 11.2 ​% and 1.3 ​% respectively, while the mean accuracy in N-back tests increased by 0.1 ​%. Furthermore, there existed several automation levels of tasks where the task performance remained almost unchanged under normal operation. The function of task automation on decreasing mental load reduced in the following order: A3-B3-C2-D2-E2, A2-B2-C2-D2-E2, and A3-B3-C1-D1-E1. The main contribution of this research was to provide a qualitative method and framework for the evaluation of influences of automation level on operators’ mental load, and the design of human-machine interaction and adaptive automation in automated systems.

The effect of morning commutes on emotional exhaustion and task performance: Taking mental effort and cognitive appraisal into account

Prior research has demonstrated the negative effects of commuting on various employee outcomes, mostly attributing these effects to objective characteristics of the commute (e.g., travel time and distance). Yet different employees respond to similar commuting conditions in different ways. We draw from the conservation of resources theory and the transactional theory of stress and coping to examine whether and how cognitive evaluation of the morning commute shapes employees’ responses to the amount of capacity required during the commute. The results, based on survey and diary data collected from 110 employees, suggest that mental effort and cognitive appraisal of the morning commute, individually and jointly are associated with emotional exhaustion upon arrival at work. In addition, the association between mental effort and task performance is fully mediated by emotional exhaustion. We discuss the importance of cognitive commuting appraisal as an aspect of commuting that is potentially malleable to change through training.

Personalized optimal room temperature and illuminance for maximizing occupant's mental task performance using physiological data

Indoor room temperature and illuminance level are critical factors of indoor environment quality (IEQ), affecting human mental task performance. These effects are reflected in their physiological responses such as heart rate, electrodermal activity, and skin temperature. Occupants' individual preferences, sensitivity, and physiological responses to different combinations of room temperature and illuminance level can differ among individuals. Despite previous studies investigating the individual and combined effects of different IEQ parameters, the limited research on the cross-modal relationship between room temperature and illuminance level and its impact on mental task performance highlights its significance. Moreover, to achieve personalized insights, it is essential to incorporate individual physiological responses, and this necessitates the development of an optimization model to comprehensively examine their impact. To address these issues, this study proposes a personalized model that optimizes room temperature and illuminance levels to enhance mental task performance using occupants' physiological data. Having the random forest algorithm, this study first predicted mental task performance, which includes four mental abilities such as attention, perception, working memory, and thinking ability using the occupant's physiological data. Then, the particle swarm optimization algorithm was employed to optimize room temperature and illuminance level to maximize the predicted mental task performance. The results of the proposed model align with observed values of room temperature and illuminance level during experiments, validating the adoption of a personalized approach. The findings contribute to future insights and guidelines for the design and management of indoor environments to maximize occupants' performance.

Exploring Trait-like Neurophysiological Predictors of Shared Mental Model and Task Performance

Exploring Trait-like Neurophysiological Predictors of Shared Mental Model and Task Performance

Working hard but not tired? The influence of task valuation on mental fatigue, effort investment, and task performance.

It has been demonstrated in previous studies that prolonged mental effort exertion evokes mental fatigue and leads to impairments in task performance. In the current investigation, we aimed to test the hypothesis that mental fatigue depends on motivational processes and can be influenced by task valuation. In two studies, we experimentally manipulated the value of the task by financial rewards (Study 1) and the sense of autonomy (Study 2). Contrary to our predictions, those manipulations did not influence the main dependent variables. We also introduced additional rewards after prolonged effort exertion. In line with our expectations, the results showed that mental fatigue increases with time spent on effortful tasks. Importantly, however, mental fatigue decreases when the value of the task rises. This effect is accompanied by stronger effort engagement and improvement in task performance. The findings support the motivational theories of mental effort and fatigue, showing that mental fatigue might serve as a signal of diminishing value of the ongoing task.

Assessing cognitive effects of transportation noise on office workers with physiology and task performance

Noise typically present in offices can negatively impact workers’ mental workload and task performance. This study investigated how transportation noise in open offices when windows are open can influence workers’ task performance, physiology (brain activity, heart rate variability, and skin resistance), and subjective ratings, as previous literature works often show inconclusive results or use unrealistic, simulated acoustic conditions. Subjects were given two cognitive tasks, mental arithmetic and digit span, while wearing three physiological measurement devices: an electroencephalography (EEG) headset, electrocardiogram (ECG) sensors, and electrodermal activity (EDA) sensors. After a baseline measurement, both the physiological markers and task performance were recorded for a training session, a quiet condition, and two transportation noise conditions with sound pressure levels of 50 and 70 dBA, respectively. Recorded rail noise was auralized in an anechoic chamber with a 32-loudspeaker array to simulate transportation noise heard when sitting in an office with an open window. Subjective rating questions regarding the acoustic environment and self-perception of mental workload and performance were administered after each acoustic condition. The effects of different acoustic conditions on cognitive task performance, physiological data, and subjective ratings were analyzed with a repeated measures MANOVA. Findings from this study will be presented.

EEG-Based Mental Tasks Recognition via a Deep Learning-Driven Anomaly Detector.

This paper introduces an unsupervised deep learning-driven scheme for mental tasks' recognition using EEG signals. To this end, the Multichannel Wiener filter was first applied to EEG signals as an artifact removal algorithm to achieve robust recognition. Then, a quadratic time-frequency distribution (QTFD) was applied to extract effective time-frequency signal representation of the EEG signals and catch the EEG signals' spectral variations over time to improve the recognition of mental tasks. The QTFD time-frequency features are employed as input for the proposed deep belief network (DBN)-driven Isolation Forest (iF) scheme to classify the EEG signals. Indeed, a single DBN-based iF detector is constructed based on each class's training data, with the class's samples as inliers and all other samples as anomalies (i.e., one-vs.-rest). The DBN is considered to learn pertinent information without assumptions on the data distribution, and the iF scheme is used for data discrimination. This approach is assessed using experimental data comprising five mental tasks from a publicly available database from the Graz University of Technology. Compared to the DBN-based Elliptical Envelope, Local Outlier Factor, and state-of-the-art EEG-based classification methods, the proposed DBN-based iF detector offers superior discrimination performance of mental tasks.

Fitness tracking reveals task-specific associations between memory, mental health, and physical activity

Physical activity can benefit both physical and mental well-being. Different forms of exercise (e.g., aerobic versus anaerobic; running versus walking, swimming, or yoga; high-intensity interval training versus endurance workouts; etc.) impact physical fitness in different ways. For example, running may substantially impact leg and heart strength but only moderately impact arm strength. We hypothesized that the mental benefits of physical activity might be similarly differentiated. We focused specifically on how different intensities of physical activity might relate to different aspects of memory and mental health. To test our hypothesis, we collected (in aggregate) roughly a century’s worth of fitness data. We then asked participants to fill out surveys asking them to self-report on different aspects of their mental health. We also asked participants to engage in a battery of memory tasks that tested their short and long term episodic, semantic, and spatial memory performance. We found that participants with similar physical activity habits and fitness profiles tended to also exhibit similar mental health and task performance profiles. These effects were task-specific in that different physical activity patterns or fitness characteristics varied with different aspects of memory, on different tasks. Taken together, these findings provide foundational work for designing physical activity interventions that target specific components of cognitive performance and mental health by leveraging low-cost fitness tracking devices.

Intrauterine Device Use: A New Frontier for Behavioral Neuroendocrinology.

Intrauterine devices (IUDs) are the most-used reversible contraceptive method for women in the world, but little is known about their potential modulation of brain function, cognition, and behavior. This is disconcerting because research on other hormonal contraceptives, especially oral contraceptives (OCs), increasingly shows that exogenous sex hormones have behavioral neuroendocrine consequences, especially for gendered cognition, including spatial skills. Effects are small and nuanced, however, partially reflecting heterogeneity. The goal of this paper is to introduce IUD use as a new frontier for basic and applied research, and to offer key considerations for studying it, emphasizing the importance of multimodal investigations and person-specific analyses. The feasibility and utility of studying IUD users is illustrated by: scanning women who completed a functional magnetic resonance imaging mental rotations task; taking an individualized approach to mapping functional connectivity during the task using network analyses containing connections common across participants and unique to individual women, focusing on brain regions in putative mental rotations and default mode networks; and linking metrics of brain connectivity from the individualized networks to both mental rotations task performance and circulating hormone levels. IUD users provide a promising natural experiment for the interplay between exogenous and endogenous sex hormones, and they are likely qualitatively different from OC users with whom they are often grouped in hormonal contraceptive research. This paper underscores how future research on IUD users can advance basic neuroendocrinological knowledge and women’s health.

DIFFERENCES BETWEEN MEN AND WOMEN IN COGNITIVE STRATEGIES APPLIED IN MENTAL ROTATION TASKS

This article aims to outline the differences between men and women in cognitive strategies applied in mental rotation task. Mental rotation is recognised among the fundamental processes of spatial thinking. Good ability to assess the spatial relations between oneself and the surrounding makes it possible to take decisions quickly and to act effectively. Mental rotation tasks can be performed in various ways, depending on their type, and with a use of different cognitive strategies. The study explores characteristics of mental rotation task performance specific to women and men. The differences observed in this area are determined by multiple factors. It was pointed out that interactions between biological and environmental factors are of major importance for effective performance in mental rotation tasks. The discussion also focuses on task characteristics possibly determining different results achieved by men and women, and potentially affecting the choice of specific strategies applied in mental rotation tasks. Subsequently, the article reviews the evidence suggesting differences in cognitive strategies used during mental rotation tasks by women and men. It is also pointed out that, in the context of the observed sex-related differences, the type of strategies used are associated with methods of assessing visuospatial material and with task characteristics. The final part presents data from neuroimaging studies investigating brain activity recorded during performance of this type of tasks. The evidence was discussed with reference to sex differences in cognitive strategies applied in mental rotation tasks.

Eye-Tracking for Performance Evaluation and Workload Estimation in Space Telerobotic Training

Monitoring the mental workload of operators is of paramount importance in space telerobotic training and other teleoperation tasks. Instead of the estimation of task-specific workload, this article aims at investigating the impact of two significant confounding factors (time-pressure and latency) on space teleoperation and explored the use of eye-tracking technology for factor-induced mental workload estimation and performance evaluation. Ten subjects teleoperated a Canadarm2 robot to complete a complex on-orbit assembly task in our photo-realistic training simulator while wearing a head-mounted eye-tracker. To understand how time-pressure and latency influence eye-tracking features works, we first performed the statistical analysis on various features with respect to a single factor and across multiple groups. Next, eye-tracking features extracted from segment data and trial data is used to identify the mental workload induced by confounding factors, which can be used for developing personalized training programs and guaranteeing safe teleoperation. Furthermore, to improve the recognition performance using segment data, we propose the activity ratio and time ratio to characterize the informative segments. Finally, the relationship between simulator-defined performance measures and eye-tracking features is examined. Results show that fixation duration, saccade frequency and duration, pupil diameter, and index of pupillary activity are significant features that can be used in both factor-induced mental workload estimation and task performance evaluation.

See, Hear, or Feel - to Speak: A Versatile Multiple-Choice Functional Near-Infrared Spectroscopy-Brain-Computer Interface Feasible With Visual, Auditory, or Tactile Instructions.

Severely motor-disabled patients, such as those suffering from the so-called “locked-in” syndrome, cannot communicate naturally. They may benefit from brain-computer interfaces (BCIs) exploiting brain signals for communication and therewith circumventing the muscular system. One BCI technique that has gained attention recently is functional near-infrared spectroscopy (fNIRS). Typically, fNIRS-based BCIs allow for brain-based communication via voluntarily modulation of brain activity through mental task performance guided by visual or auditory instructions. While the development of fNIRS-BCIs has made great progress, the reliability of fNIRS-BCIs across time and environments has rarely been assessed. In the present fNIRS-BCI study, we tested six healthy participants across three consecutive days using a straightforward four-choice fNIRS-BCI communication paradigm that allows answer encoding based on instructions using various sensory modalities. To encode an answer, participants performed a motor imagery task (mental drawing) in one out of four time periods. Answer encoding was guided by either the visual, auditory, or tactile sensory modality. Two participants were tested outside the laboratory in a cafeteria. Answers were decoded from the time course of the most-informative fNIRS channel-by-chromophore combination. Across the three testing days, we obtained mean single- and multi-trial (joint analysis of four consecutive trials) accuracies of 62.5 and 85.19%, respectively. Obtained multi-trial accuracies were 86.11% for visual, 80.56% for auditory, and 88.89% for tactile sensory encoding. The two participants that used the fNIRS-BCI in a cafeteria obtained the best single- (72.22 and 77.78%) and multi-trial accuracies (100 and 94.44%). Communication was reliable over the three recording sessions with multi-trial accuracies of 86.11% on day 1, 86.11% on day 2, and 83.33% on day 3. To gauge the trade-off between number of optodes and decoding accuracy, averaging across two and three promising fNIRS channels was compared to the one-channel approach. Multi-trial accuracy increased from 85.19% (one-channel approach) to 91.67% (two-/three-channel approach). In sum, the presented fNIRS-BCI yielded robust decoding results using three alternative sensory encoding modalities. Further, fNIRS-BCI communication was stable over the course of three consecutive days, even in a natural (social) environment. Therewith, the developed fNIRS-BCI demonstrated high flexibility, reliability and robustness, crucial requirements for future clinical applicability.

General Intelligence: An Analysis of the Saudi Students’ General Mental Ability and Elementary Cognitive Task Performance

Previous studies on human intelligence has revealed that varied factors influence cognitive performance, and some studies have hypothesized the presence of &amp;ldquo;general intelligence&amp;rdquo; (g factor) that is responsible for intelligence. However, most studies have been centered on Western cultures. This study thus examines the Saudi students and the g factor hypothesis. A group of Saudi college students participated in a battery of general mental ability tests and elementary cognitive tasks and were assessed for the influence of various factors on cognitive performance. The study results revealed an increase in the average of Saudi students&amp;rsquo; intelligence compared to the results of the previous studies, but it did not yield a g factor.

Mental rotation task performance in relation to sexual and gender diversity in Thailand

Neurohormonal theory argues that organizational effects of hormone exposure influence sexual orientation and gender identity, as well as sex differences in visuospatial cognition. This study examined mental rotation task (MRT) performance in a diverse Thai sample (N = 980). Thai culture has several third genders: individuals assigned male at birth (AMAB) who are feminine and attracted to cis men (i.e., sao praphet song); individuals assigned female at birth (AFAB) who are masculine and attracted to feminine individuals (i.e., toms); AFAB individuals who are feminine and attracted to toms (i.e., dees); and sexual orientation categories similar to Western culture (e.g., gay, lesbian, bi). On the MRT, straight cis men outperformed straight cis women. Results were consistent with organizational effects among AMAB individuals, with straight cis men outperforming gay cis men and sao praphet song. Among AFAB individuals, however, only bi and lesbian cis women outperformed dees. Overall, support for neurohormonal theory was limited among AFAB individuals, but MRT performance among AMAB individuals was consistent with organizational effects. This study informs our understanding of visuospatial sex/gender differences and the applicability of neurohormonal theory across cultures.