Lower Mental Workload Research Articles

Mental Workload Estimation Based on Physiological Features for Pilot-UAV Teaming Applications.

Manned-Unmanned Teaming (MUM-T) can be defined as the teaming of aerial robots (artificial agents) along with a human pilot (natural agent), in which the human agent is not an authoritative controller but rather a cooperative team player. To our knowledge, no study has yet evaluated the impact of MUM-T scenarios on operators' mental workload (MW) using a neuroergonomic approach (i.e., using physiological measures), nor provided a MW estimation through classification applied on those measures. Moreover, the impact of the non-stationarity of the physiological signal is seldom taken into account in classification pipelines, particularly regarding the validation design. Therefore this study was designed with two goals: (i) to characterize and estimate MW in a MUM-T setting based on physiological signals; (ii) to assess the impact of the validation procedure on classification accuracy. In this context, a search and rescue (S&R) scenario was developed in which 14 participants played the role of a pilot cooperating with three UAVs (Unmanned Aerial Vehicles). Missions were designed to induce high and low MW levels, which were evaluated using self-reported, behavioral and physiological measures (i.e., cerebral, cardiac, and oculomotor features). Supervised classification pipelines based on various combinations of these physiological features were benchmarked, and two validation procedures were compared (i.e., a traditional one that does not take time into account vs. an ecological one that does). The main results are: (i) a significant impact of MW on all measures, (ii) a higher intra-subject classification accuracy (75%) reached using ECG features alone or in combination with EEG and ET ones with the Adaboost, Linear Discriminant Analysis or the Support Vector Machine classifiers. However this was only true with the traditional validation. There was a significant drop in classification accuracy using the ecological one. Interestingly, inter-subject classification with ecological validation (59.8%) surpassed both intra-subject with ecological and inter-subject with traditional validation. These results highlight the need for further developments to perform MW monitoring in such operational contexts.

Does heavy mental workload affect moral sensitivity among critical care unit nursing professionals? a cross-sectional study

BackgroundMoral sensitivity creates the basic attitude in providing effective ethical care to patients. Heavy mental workload is a major concern of critical care nursing professionals, which could adversely affect nursing staff and patients. The present study aimed to investigate the effects of mental workload and some demographic variables on the moral sensitivity of critical care nursing professionals.MethodsThis cross-sectional, descriptive-correlational study was performed on 181 nursing professionals working in the critical care units of Shahid Rajaei Cardiovascular Medical and Research Center in Tehran, Iran. Data were collected using a demographic questionnaire, the moral sensitivity questionnaire, and the NASA-task load index to assess mental workload. Data analysis was performed in SPSS version 22 using descriptive statistics, independent t-test, Pearson’s correlation-coefficient, and regression analysis.ResultsThe results of regression analysis yielded no statistical significant relationship between heavy mental workload and moral sensitivity of the critical care nursing professionals, while clinical experience had a positive, significant association with moral sensitivity.ConclusionsAlthough care nursing professionals experience a heavy mental workload in critical care units, it does not decrease their moral sensitivity. In addition, experienced nurses have higher moral sensitivity and lower mental workload. Therefore, it seems that nursing managers should pay special attention to the importance of employing experienced nurses along with younger nurses.

Comparing interventions to reduce boredom in a low mental workload environment

ABSTRACT Boredom is a common workplace problem. Previous research has suggested that repetitive and monotonous work tasks may lead to boredom. However, these tasks have been reduced due to increased workplace automation. Thus, the current cause of boredom may be due to low mental workload. This research developed a general boredom model and compared the effects of feedback type (performance and ranking) and intervention method (game and quiz) on boredom and task performance. Results revealed that the secondary task interventions can reduce boredom and feedback could shorten the response time. Gender also had a significant influence on response time. Notably, results revealed a 4% probability of task failure during the experiment, indicating other interventions are also required. This research indicates that interventions to reduce boredom caused by low mental workload should be designed differently from tasks that have been designed to combat the boredom caused by repetitive and monotonous work.

Visual Scanning Techniques and Mental Workload of Helicopter Pilots During Simulated Flight.

INTRODUCTION: The visual scanning techniques used by helicopter pilots are a critical skill to accomplish safe and correct landing. According to the human information processing theory, visual scanning techniques can be analyzed as a function of fixation location, number, and duration of fixations.METHODS: This study assessed these techniques in expert and novice pilots during an open sea flight simulation in a low-workload condition, consisting of a daylight and good weather simulation, and in a high-workload condition of night-time, low visibility, and adverse weather conditions. Taking part in the study were 12 helicopter pilots. Mental workload was assessed through psychological measures (NASA-TLX). The pilots performance was assessed and eye movements were recorded using an eye-tracker during four phases of the flight simulations.RESULTS: Overall, pilots made more fixations out of the window (OTW; 22.54) than inside the cockpit (ITC; 11.08), Fixations were longer OTW (830.17 ms) than ITC (647.97 ms) and they were shorter in the low-demand condition (626.27 ms). Further, pilots reported higher mental workload (NASA-TLX) in the high-demand condition compared to the low-demand condition, regardless of their expertise, and expert pilots reported a lower mental workload compared to novice pilots.DISCUSSION: Pilots performance and perceived mental workload varied as a function of expertise and flight conditions. Pilots rely on instrument support during the cruise phase and external visual cues during the landing phase. The implications for a new visual landing system design are discussed.Rainieri G, Fraboni F, Russo G, Tul M, Pingitore A, Tessari A, Pietrantoni L. Visual scanning techniques and mental workload of helicopter pilots during simulated flight. Aerosp Med Hum Perform. 2021; 92(1):1119.

Toward neuroadaptive support technologies for improving digital reading: a passive BCI-based assessment of mental workload imposed by text difficulty and presentation speed during reading

We investigated whether a passive brain–computer interface that was trained to distinguish low and high mental workload in the electroencephalogram (EEG) can be used to identify (1) texts of different readability difficulties and (2) texts read at different presentation speeds. For twelve subjects we calibrated a subject-dependent, but task-independent predictive model classifying mental workload. We then recorded EEG data from each subject, while twelve texts in blocks of three were presented to them word by word. Half of the texts were easy, and the other half were difficult texts according to classic reading formulas. From each text category three texts were read at a self-adjusted comfortable presentation speed and the other three at an increased speed. For each subject we applied the predictive model to EEG data of each word of the twelve texts. We found that the resulting predictive values for mental workload were higher for difficult texts than for easy texts. Predictive values from texts presented at an increased speed were also higher than for those presented at a normal self-adjusted speed. The results suggest that the task-independent predictive model can be used on single-subject level to build a highly predictive user model of the reader over time. Such a model could be employed in a system which continuously monitors brain activity related to mental workload and adapts to specific reader’s abilities and characteristics by adjusting the difficulty of text materials and the way it is presented to the reader in real time. A neuroadaptive system like this could foster efficient reading and text-based learning by keeping readers’ mental workload levels at an individually optimal level.

The effects of elevated carbon dioxide concentration and mental workload on task performance in an enclosed environmental chamber

In an enclosed environmental chamber, fifteen participants were recruited to investigate the effects of elevated carbon dioxide (CO2) concentration and mental workload on their task performance. During each CO2 condition, the Multi-attribute Task Battery (MATB) tasks with low, medium, and high mental workload were separately carried out in the order designed by the Latin square method. The MATB task performance was synchronously collected, and the subjective mental workload was measured immediately after each task based on the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) scale. The generalized additive mixed effect model (GAMM) results showed that the subjective mental workload was not associated with CO2 concentration and was positively related to the designed mental workload of tasks. The elevated mental workload of task had a significant inverted U-shaped effect on the MATB task performance, which aligned with prior studies and indicated that the medium mental workload was conducive to improving task performance. The MATB task performance declined significantly when the CO2 concentration increased from 1500 ppm to 3500 ppm, but there was no significant difference between 3500 ppm and 5000 ppm, or 1500 ppm and 5000 ppm.

Mental Workload Classification Method Based on EEG Independent Component Features

Excessive mental workload will reduce work efficiency, but low mental workload will cause a waste of human resources. It is very significant to study the mental workload status of operators. The existing mental workload classification method is based on electroencephalogram (EEG) features, and its classification accuracy is often low because the channel signals recorded by the EEG electrodes are a group of mixed brain signals, which are similar to multi-source mixed speech signals. It is not wise to directly analyze the mixed signals in order to distinguish the feature of EEG signals. In this study, we propose a mental workload classification method based on EEG independent components (ICs) features, which borrows from the blind source separation (BSS) idea of mixed speech signals. This presented method uses independent component analysis (ICA) to obtain pure signals, i.e., ICs. The energy features of ICs are directly extracted for classifying the mental workload, since this method directly uses ICs energy features for feature extraction. Compared with the existing solution, the proposed method can obtain better classification results. The presented method might provide a way to realize a fast, accurate, and automatic mental workload classification.

Prevalence and Contributing Factors of Low Back Pain among Nurses in Tertiary Level Hospital

Background: Low back pain is one of the common musculoskeletal health problems that occur most commonly in nurses among all Health workers. Different researches showed that nurses are suffering from low back pain due to many factors. This research was conducted to find the prevalence and contributing factors of low back pain among nurses.
 Method: The descriptive cross-sectional study was done among 110 nurses by using stratified proportionate random sampling method. Semi structured self-administered questionnaire with single and multiple responses was administered among nurses after taking informed consent. Statistical package for social sciences (SPSS) 20 was used for analysis of data. Descriptive statistic (percentage and frequency) and inferential statistic (chi square) was used for the study.
 Result: Among 110 nurses, 64.5% were affected from low back pain and prevalence of low back pain of one year and one week was 60% and 20% respectively. The present working area was strongly associated with low back pain (p=0.000). Prolong standing (64.54%), bending and twisting (64.54%), heavy workload (62.72%), working in same positions (58.18%) were perceived factors of low back pain but heavy mental workload had no relationship with low back pain. Taking rest (99.1%), physiotherapy (92.7%) and taking medication (82.7%) were the factors that decreased low back pain. There was increased work restriction (46.4) and less productive and creative (42.7) due to low back pain.
 Conclusion: More than half of nurses were affected from low back pain. Prolonged standing, physical workload, bending and twisting were main contributing factors. Therefore, it is recommended to maintain proper body mechanics, periodic screening and timely rotation of nurses for the prevention of low back pain.

ANALISIS BEBAN KERJA MENTAL PADA STAF UNIT PELAKSANA TEKNIS DENGAN MENGGUNAKAN METODE NASA TLX (STUDI KASUS: UNIVERSITAS TEKNOLOGI SUMBAWA)

Physical and mental activity is the main point that causes the workload to be commonly experienced by the staff. Therefore, the workload can be said to be a relationship between the ability of workers and the amount of pressure experienced in doing a job. Generally, workloads that are often experienced by technical service Unit staff (UPT) are mental workloads that are caused by working environment conditions (universities), tolerance in work and the amount of pressure experienced in the work. The scope that became the focus in this research is the Sumbawa University of Technology which has 10 UPT (UPT Library, UPT Language Center, UPT new student admissions, UPT International Office, UPT Scholarship, UPT Cooperation, UPT information technology, UPT Public relations and Protokoler, UPT creative spaces and UPT forest management education and research) which each UPT has different workloads. The measurement of mental workloads in this study uses The NASA TLX method (The National Aeronautics and Space Administration Task Load Index) by means of The feeding and weight-bearing of The filling of the questionnaire by the staff in each UPT. The results showed that the UPT that has the lowest mental workload is the UPT Library (54.5), the moderate mental workload is the UPT Language Center (77.4), the highest mental workload i.e. UPT Scholarship (86.4).

Evaluating an Immersive Space-Time Cube Geovisualization for Intuitive Trajectory Data Exploration.

A Space-Time Cube enables analysts to clearly observe spatio-temporal features in movement trajectory datasets in geovisualization. However, its general usability is impacted by a lack of depth cues, a reported steep learning curve, and the requirement for efficient 3D navigation. In this work, we investigate a Space-Time Cube in the Immersive Analytics domain. Based on a review of previous work and selecting an appropriate exploration metaphor, we built a prototype environment where the cube is coupled to a virtual representation of the analyst's real desk, and zooming and panning in space and time are intuitively controlled using mid-air gestures. We compared our immersive environment to a desktop-based implementation in a user study with 20 participants across 7 tasks of varying difficulty, which targeted different user interface features. To investigate how performance is affected in the presence of clutter, we explored two scenarios with different numbers of trajectories. While the quantitative performance was similar for the majority of tasks, large differences appear when we analyze the patterns of interaction and consider subjective metrics. The immersive version of the Space-Time Cube received higher usability scores, much higher user preference, and was rated to have a lower mental workload, without causing participants discomfort in 25-minute-long VR sessions.

Compatibility between Shift Work and Chronotype in Indonesian Air Traffic Control’ Workers: View of Performance and Mental Workload

Shift work is commonly found in modern industries. Shift work arrangement is problematic since working in the out of normal work is giving negative consequences. Therefore, attempts have been made to optimize shift work arrangement and to minimize the negative consequences. One approach that has been used as a base in arrange shift work is chronotype, defined as individual preferences about their sleepiness work and is partially determined by clock genes. This present study aimed to observe the effect of chronotype on shift work arrangement, from the view of performance and mental workload. 25 Air Traffic Control/ATC workers work in three shift involve in this study. Chronotype was assessed once work by Munich Chronotype Questionnaire. The performance was assessed based on sleepiness (using Karolinska Sleepiness scale) and alertness (using alertometer) in the end of each shift for every ATC worker. Separate mixed ANOVA was applied in analyzing the result. This study reveals that people work in a shift work that is compatible with the chronotype perceive significant lower mental workload, slightly better alertness and slightly lower sleepiness than people work in a shift work that is not compatible with the chronotype. The implication of the result is discussed.

Augmented Reality Improves Procedural Work on an International Space Station Science Instrument

The purpose of the current study was to determine whether an augmented reality instruction method would result in faster task completion times, lower mental workload, and fewer errors for simple tasks in an operational setting. Prior research on procedural work that directly compared augmented reality instructions to traditional instruction methods (e.g., paper) showed that augmented reality instructions can enhance procedural work, but this was not true for simple tasks in an operational setting. Participants completed simple procedural tasks on spaceflight hardware using an augmented reality instruction method and a paper instruction method. Our results showed that the augmented reality instruction method resulted in faster task completion times and lower levels of mental and temporal demand compared with paper instructions. When participants used the augmented reality instruction method before the paper instruction method, there was a transfer of training that improved a subsequent procedure using the paper instruction method. An off-the-shelf augmented reality head-mounted display (HoloLens) can enhance procedural work for simple tasks in an operational setting. The ability of augmented reality to enhance procedural work for simple tasks in an operational setting can help in reducing costs and mitigating risks that could ultimately lead to accidents and critical failures.

Dissociation Between Mental Workload, Performance, and Task Awareness in Pilots of High Performance Aircraft

The purpose of this study was to demonstrate how the inclusion of a tactical task goal awareness measure complemented mental workload and performance measures in a simulated air combat mission. It was hypothesized that the evaluation of the tactical task goal awareness could provide additional information concerning the cognitive demands a pilot is exposed to during a complex air combat task. A test setting was developed to test this hypothesis in a virtual flight training device. To highlight the impact of task complexity, high performance aircraft pilots' heart rate (HR), interbeat-interval (IBI), and performance in two simple flying tasks were first compared. Then, a similar comparison, complemented with the tactical task goal awareness measure, was made with two complex flying tasks. It was found that when the pilot's awareness of the tactical goals was low, a combination of low performance and low mental workload occurred. It was concluded that when the pilots' performance is evaluated on a complex air combat task, the awareness of the tactical goals, performance, and mental workload should be studied together as the pilot's awareness can explain some of HR/IBI responses that could be otherwise misinterpreted. More generally, mental workload, performance, and task goal awareness should all be considered when the operator's performance in any complex human-machine system is assessed.

Learning Spatial-Spectral-Temporal EEG Features With Recurrent 3D Convolutional Neural Networks for Cross-Task Mental Workload Assessment.

Mental workload assessment is essential for maintaining human health and preventing accidents. Most research on this issue is limited to a single task. However, cross-task assessment is indispensable for extending a pre-trained model to new workload conditions. Because brain dynamics are complex across different tasks, it is difficult to propose efficient human-designed features based on prior knowledge. Therefore, this paper proposes a concatenated structure of deep recurrent and 3D convolutional neural networks (R3DCNNs) to learn EEG features across different tasks without prior knowledge. First, this paper adds frequency and time dimensions to EEG topographic maps based on a Morlet wavelet transformation. Then, R3DCNN is proposed to simultaneously learn EEG features from the spatial, spectral, and temporal dimensions. The proposed model is validated based on the EEG signals collected from 20 subjects. This paper employs a binary classification of low and high mental workload across spatial n-back and arithmetic tasks. The results show that the R3DCNN achieves an average accuracy of 88.9%, which is a significant increase compared with that of the state-of-the-art methods. In addition, the visualization of the convolutional layers demonstrates that the deep neural network can extract detailed features. These results indicate that R3DCNN is capable of identifying the mental workload levels for cross-task conditions.

Implementing Cognitive Training Into a Surgical Skill Course: A Pilot Study on Laparoscopic Suturing and Knot Tying.

Mini-invasive surgery-for example, laparoscopy-has challenged surgeons' skills by extending their usual haptic space and displaying indirect visual feedback through a screen. This may require new mental abilities, including spatial orientation and mental representation. This study aimed to test the effect of cognitive training based on motor imagery (MI) and action observation (AO) on surgical skills. A total of 28 postgraduate residents in surgery took part in our study and were randomly distributed into 1 of the 3 following groups: (1) the basic surgical skill, which is a short 2-day laparoscopic course + MI + AO group; (2) the basic surgical skill group; and (3) the control group. The MI + AO group underwent additional cognitive training, whereas the basic surgical skill group performed neutral activity during the same time. The laparoscopic suturing and knot tying performance as well as spatial ability and mental workload were assessed before and after the training period. We did not observe an effect of cognitive training on the laparoscopic performance. However, the basic surgical skill group significantly improved spatial orientation performance and rated lower mental workload, whereas the 2 others exhibited lower performance in a mental rotation test. Thus, actual and cognitive training pooled together during a short training period elicited too high a strain, thus limiting potential improvements. Because MI and AO already showed positive outcomes on surgical skills, this issue may, thus, be mitigated according to our specific learning conditions. Distributed learning may possibly better divide and share the strain associated with new surgical skills learning.

A P300 auditory brain-computer interface based on mental repetition

Objective. The current study evaluates an auditory brain-computer interface (BCI) protocol that allows users to mentally choose among 6 options. Methods. The protocol is based on an oddball P300 paradigm. To reduce mental workload, we introduce a change in the typical oddball paradigm task: instead of passively counting the presented target auditory stimuli, we ask participants to simply mentally repeat them when they occur. In the study, ten healthy participants carried out two calibration sessions respectively with traditional mental count and with the proposed mental repetition and then three free item selection sessions using mental repetition. A comparison has been conducted between off-line count and mental repetition classification accuracies achieved by each participant during the calibration sessions. The mental workload difference between the count and repeat calibration sessions of each participant was evaluated by computing alpha (at Po8) and theta (at Fz) spectral power density (SPD) curves. Results. Nine out of ten participants showed a higher mental workload with the traditional mental count. The repeat activity was preferred by 8 out of 10 participants. The comparison conducted between off-line count and mental repetition classification accuracies shows a slightly worse average behavior for the repeat protocol in the first 8 averaged trials. With the proposed protocol we got an average on-line item-selection information transfer rate (ITR) over 2 trials of 2.35 bits min−1, and an average on-line accuracy over 10 trials of 81.7%. Conclusions. Although off-line classification based on mental count data got slightly better results, the proposed auditory BCI protocol with mental repetition achieved an on-line performance similar to the traditional counting oddball paradigm task but with a lower mental workload. Significance. The results obtained with healthy subjects suggest that the proposed protocol can be a simpler alternative to the mental count, with comparable performance and lower mental load.

Influence of mental workload on detecting information varieties revealed by mismatch negativity during flight simulation

Behavioral and physiological measures indexed by frontal mismatch negativity (MMN), temporal MMN and eye blink rate derived from electrooculogram (EOG) were used to assess the mental workload related to flight simulation tasks. A total of 14 healthy flying cadets carried out flight simulation tasks under high and low mental workload conditions respectively. The mental workload conditions were manipulated by the complexity of abnormal attitude identification task presented on the head-up display (HUD) during the cruise phase. In this experiment, the increasing mental workload was associated with decreased accuracy rate of detecting abnormal information and longer reaction time. The frontal MMN was enhanced under the high mental workload condition whereas the temporal MMN was decreased, reflecting different information processing mechanisms. In addition, the eye blink rate, an additional assessment of mental workload, also showed high sensitivity and decreased significantly with the increase of mental workload. These results suggested that high mental workload might influence operator's pre-attentive change detection.

ANALISIS HUBUNGAN BEBAN KERJA MENTAL DENGAN STRES KERJA DI INSTALASI CSSD RUMAH SAKIT UMUM HAJI SURABAYA

ABSTRACT Mental workload is a workload which is the difference between the demands of the workload of a task with a maximum capacity load of a person's mental condition motivated, excessive workload will lead to the incident of stress. Work stress is distress experienced by employees when facing job. The purpose of this research was to study the picture of mental workload and stress on employees who work in CSSD Installation General Hospital Haji Surabaya. This research was a descriptive cross sectional approach. The subjects of this research were employees in the Installation CSSD General Hospital Haji Surabaya. The variables of this research were the mental workload and job stress. Primary data was collected using questionnaires and observation. Secondary data obtained from the General Hospital Haji Surabaya. Furthermore the data was processed by descriptive and described in narrative form. The results showed that the CSSD employees experiencing mental workload which was divided into seven employees experiencing medium metal workload and four employees experiencing low mental workload . In addition there was a relationship between mental workload with the incidence of workplace stress. overall it can be described that mental workload and workplace stress were in the medium level. It was recommended that employees can used the time off well and getting used to exercise to increase endurance. Keywoard : mental workload, workplace stress, installation sterilization center

Effects of galvanic skin response feedback on user experience in gaze-controlled gaming: A pilot study.

Eye-tracking (ET) is one of the most intuitive solutions for enabling people with severe motor impairments to control devices. Nevertheless, even such an effective assistive solution can detrimentally affect user experience during demanding tasks because of, for instance, the user's mental workload - using gaze-based controls for an extensive period of time can generate fatigue and cause frustration. Thus, it is necessary to design novel solutions for ET contexts able to improve the user experience, with particular attention to its aspects related to workload. In this paper, a pilot study evaluates the effects of a relaxation biofeedback system on the user experience in the context of a gaze-controlled task that is mentally and temporally demanding: ET-based gaming. Different aspects of the subjects' experience were investigated under two conditions of a gaze-controlled game. In the Biofeedback group (BF), the user triggered a command by means of voluntary relaxation, monitored through Galvanic Skin Response (GSR) and represented by visual feedback. In the No Biofeedback group (NBF), the same feedback was timed according to the average frequency of commands in BF. After the experiment, each subject filled out a user experience questionnaire. The results showed a general appreciation for BF, with a significant between-group difference in the perceived session time duration, with the latter being shorter for subjects in BF than for the ones in NBF. This result implies a lower mental workload for BF than for NBF subjects. Other results point toward a potential role of user's engagement in the improvement of user experience in BF. Such an effect highlights the value of relaxation biofeedback for improving the user experience in a demanding gaze-controlled task.

Effects of three‐dimensional virtual reality and traditional training methods on mental workload and training performance

AbstractIndustries will implement effective training programs to improve training performance, and an ideal training performance occurs under proper mental workload (MWL). Virtual reality (VR) has recently been widely utilized in training; however, only a few studies have investigated its effects on MWL and training performance simultaneously. The purpose of this study is to investigate the effects of VR training and traditional training methods, such as technical manuals (TM) and multimedia films (MF), on training performance and MWL. The results of the performance measurement show that VR training is considered the best training method compared to TM and MF, particularly in the case of complex tasks. The results of physiological measurements (GSR [galvanic skin response], LF% [low frequency], and LF/HF [high frequency] ratio) show a significant difference between reading TM and using computer (MF and VR), wherein the latter has a lower MWL. However, no significant difference in subjective MWL assessment (NASA‐TLX [task load index]) and HF% measurement is found.