Task Load Research Articles

XR Vest: A Novel System for Demonstration-Based Learning of Safety Skills

This work investigates the design and usability of a novel eXtended Reality (XR) Vest, which combines two viewpoints for demonstration-based training (DBT). Traditional modalities for DBT, such as pre-recorded videos and live instruction, are minimally engaging and potentially hazardous resulting in low motivation and knowledge retention. To combat this, works incorporate XR technology to improve training immersiveness, safety, and engagement. When worn by a trainer, our XR Vest enables trainees to have the first-person perspective of immersive XR environments on an integrated tablet while simultaneously watching the third-person motor movements. To test the XR Vest in DBT, twenty-eight individuals completed three training sessions 1) using an Oculus Quest 2 ( baseline), 2) watching a DBT video on a desktop computer monitor (first-person perspective), and 3) viewing a DBT on the XR Vest (first-person and third-person perspectives). Following each session, the participants performed a memory aptitude test to evaluate their recall, a NASA Task Load Index questionnaire to investigate their perceived workload, and a System Usability Scale (SUS) questionnaire to measure the usability of the systems. A linear mixed-effect analysis showed significant differences between the temporal demand, physical demand, and frustration in the NASA-TLX scores and the integration and learnability features in the SUS scores. The results suggest that incorporating XR technology in first- and third-person perspectives within the XR Vest decreased workload and improved system usability. Future works should evaluate the benefits of this XR design in other domains where DBT is used.

Relationships Between Experience, Sleepiness, Height, Reported Task Load, and Performance Scores in Teleoperators for the JET

Relationships Between Experience, Sleepiness, Height, Reported Task Load, and Performance Scores in Teleoperators for the JET

Evaluation of a Voice-Enabled Autonomous Camera Control System for the da Vinci Surgical Robot

Robotic surgery involves significant task switching between tool control and camera control, which can be a source of distraction and error. This study evaluated the performance of a voice-enabled autonomous camera control system compared to a human-operated camera for the da Vinci surgical robot. Twenty subjects performed a series of tasks that required them to instruct the camera to move to specific locations to complete the tasks. The subjects performed the tasks (1) using an automated camera system that could be tailored based on keywords; and (2) directing a human camera operator using voice commands. The data were analyzed using task completion measures and the NASA Task Load Index (TLX) human performance metrics. The human-operated camera control method was able to outperform an automated algorithm in terms of task completion (6.96 vs. 7.71 correct insertions; p-value = 0.044). However, subjective feedback suggests that a voice-enabled autonomous camera control system is comparable to a human-operated camera control system. Based on the subjects’ feedback, thirteen out of the twenty subjects preferred the voice-enabled autonomous camera control system including the surgeon. This study is a step towards a more natural language interface for surgical robotics as these systems become better partners during surgery.

Assessment of health technology acceptability for remote monitoring of patients with COVID-19: A measurement model for user perceptions of pulse oximeters.

This study aims to develop a measurement model for health technology acceptability using a theoretical framework and a range of validated instruments to measure user experience, acceptance, usability, health and digital health literacy. A cross-sectional evaluation study using a mixed-methods approach was conducted. An online survey was administered to patients who used a pulse oximeter in a virtual hospital setting during COVID-19. The model development was conducted in three steps: (1) exploratory factor analysis for conceptual model development, (2) measurement model confirmation through confirmatory factor analysis followed by structural equation modelling and (3) test of model external validity on four outcome measures. Finally, the different constructs of the developed model were used to compare two types of pulse oximeters by measuring the standardised scores. Two hundred and two participants were included in the analysis, 37.6% were female and the average age was 53 years (SD:15.38). A four-construct model comprising Task Load, Affective Attitude, Self-Efficacy and Value of Use (0.636-0.857 factor loadings) with 12 items resulted from the exploratory factor analysis and yielded a good fit (RMSEA = .026). Health and digital health literacy did not affect the overall reliability of the model. Frustration, performance, trust and satisfaction were identified as outcomes of the model. No significant differences were observed in the acceptability constructs when comparing the two pulse oximeter devices. This article proposes a model for the measurement of the acceptability of health technologies used by patients in a remote care setting based on the use of a pulse oximeter in COVID-19 remote monitoring.

Come Look at This: Supporting Fluent Transitions between Tightly and Loosely Coupled Collaboration in Social Virtual Reality.

Collaborative work in social virtual reality often requires an interplay of loosely coupled collaboration from different virtual locations and tightly coupled face-to-face collaboration. Without appropriate system mediation, however, transitioning between these phases requires high navigation and coordination efforts. In this paper, we present an interaction system that allows collaborators in virtual reality to seamlessly switch between different collaboration models known from related work. To this end, we present collaborators with functionalities that let them work on individual sub-tasks in different virtual locations, consult each other using asymmetric interaction patterns while keeping their current location, and temporarily or permanently join each other for face-to-face interaction. We evaluated our methods in a user study with 32 participants working in teams of two. Our quantitative results indicate that delegating the target selection process for a long-distance teleport significantly improves placement accuracy and decreases task load within the team. Our qualitative user feedback shows that our system can be applied to support flexible collaboration. In addition, the proposed interaction sequence received positive evaluations from teams with varying VR experiences.

Deep reinforcement learning task scheduling method based on server real-time performance.

Server load levels affect the performance of cloud task execution, which is rooted in the impact of server performance on cloud task execution. Traditional cloud task scheduling methods usually only consider server load without fully considering the server's real-time load-performance mapping relationship, resulting in the inability to evaluate the server's real-time processing capability accurately. This deficiency directly affects the efficiency, performance, and user experience of cloud task scheduling. Firstly, we construct a performance platform model to monitor server real-time load and performance status information in response to the above problems. In addition, we propose a new deep reinforcement learning task scheduling method based on server real-time performance (SRP-DRL). This method introduces a real-time performance-aware strategy and adds status information about the real-time impact of task load on server performance on top of considering server load. It enhances the perception capability of the deep reinforcement learning (DRL) model in cloud scheduling environments and improves the server's load-balancing ability under latency constraints. Experimental results indicate that the SRP-DRL method has better overall performance regarding task average response time, success rate, and server average load variance compared to Random, Round-Robin, Earliest Idle Time First (EITF), and Best Fit (BEST-FIT) task scheduling methods. In particular, the SRP-DRL is highly effective in reducing server average load variance when numerous tasks arrive within a unit of time, ultimately optimizing the performance of the cloud system.

Mental Workload and Prefrontal Brain Activity During Silent Reading Task in University Students with Problematic Smartphone Use.

Problematic smartphone use (PSU) is common among young people and linked to poor academic performance. However, how PSU affects learning processes remains unclear. This study investigated the influence of auditory cue stimulation during a reading task on the mental workload and prefrontal brain activity of young individuals with PSU. Sixteen university students with PSU and 14 healthy controls (HC) performed a silent reading task, during which fake notification sounds were introduced. Their mental workload was assessed using the NASA Task Load Index (NASA-TLX), and prefrontal brain activity was measured using functional near-infrared spectroscopy (fNIRS). The results of the NASA-TLX suggest that the PSU group experienced greater frustration than the HC group. The fNIRS results showed that in the right medial prefrontal region of the HC group, O2Hb levels increased following cue stimulation, whereas no change was observed in the PSU group. Moreover, in the HC group, HHb levels in the left lateral prefrontal region decreased after cue stimulation. The findings of the present study demonstrate that university students with PSU experience frustration and exhibit deactivation in the prefrontal regions associated with the executive control network during silent reading in realistic learning situations.

The Effects of Reading Speed on Acoustic Voice Parameters and Self-reported Vocal Fatigue in Students.

Vocal loading tasks (VLTs) help researchers gather acoustic measurements and understand how a healthy speaker adjusts their voice in response to challenges. There is a dearth of evidence measuring the impact of speaking rate in VLTs on acoustic voice parameters and vocal fatigue. In the present study, the relationships between acoustic voice parameters and self-reported vocal fatigue were examined through an experimental VLT. 38 students completed a 45-minute VLT which involved the recording of three randomized reading tasks. The tasks varied by the speed in which the words were presented (slow, medium, fast) on a computer monitor. Vocal fatigue ratings were measured subjectively using a Borg scale and negative adaptations to vocal loading were measured objectively using Sound Pressure Level (SPL, in dBA), fundamental frequency (fo, in semitones), and phonation time (Dt %). Analysis indicated that vocal fatigue increases with time, and the slope of this relationship is affected by the speaking rate. SPL and fo increased with speaking rate and the standard deviation of SPL and fo decreased with speaking rate. On average, the male participants' phonation time values were 7.8% lower than the female participants. The rate of increase of vocal fatigue with time during the experiment was higher in the fast speaking style compared to the slow and medium ones. The results provide support that the novel VLT altered multiple vocal parameters to induce measurable changes in vocal fatigue.

Correlation of Work Fatigue and Mental Workload in Train Drivers: A Cross-sectional Study.

Evidence suggests that train drivers experience a high level of fatigue and mental workload. The present study aimed to assess overall, physical, and mental fatigue levels and their correlations with the mental workload in the metro train operation. Study Design: A cross-sectional study. This study was conducted on all 1194 train drivers in the Tehran Metro. The train drivers completed the Samn-Perelli Fatigue Scale and the Fatigue Assessment Scales at the beginning and end of the shift. In addition, they completed the National Aeronautics and Space Administration Task Load Index in the middle and at the end of the shift. Correlation and regression analyses were performed on the data to test the study hypothesis. Overall, physical, and mental fatigue levels increased significantly at the end of the shift compared to the onset of the shift (P<0.001). The mental workload and related dimensions were significantly increased at the end of the shift compared to the middle of the shift (P<0.001). Mental demand was the most important workload problem among the train drivers. The highest correlation was found between overall workload and time pressure (R=0.68, P<0.001). The mental workload had a significant correlation with work fatigue in the train drivers. Control measures should be focused on the mental workload and related dimensions, especially mental demand and time pressure.

A Virtual Reality 360 Video to Introduce Second-Year Student Pharmacists to Sterile Compounding Prior to Course Activity.

Background: Virtual reality (VR) has not been used in pharmacy education when teaching sterile compounding. Objective: The objective of this study was to describe the development of a VR 360 video for second-year student pharmacists. The secondary objective was to assess the VR experience, specifically on participants' knowledge and performance in sterile compounding, as well as the VR video demands and efforts. Methods: This cross-sectional, open-label randomized study developed a VR 360 video introducing sterile compounding, created with Insta360 Pro and GoPro cameras. The video creation required two individuals to record and one individual to edit for approximately 12 hours of creation time. Participants' knowledge and performance were assessed through ten knowledge questions and the class activity rubric. The NASA Task Load Index (TLX) measured the VR experience demands and efforts for the VR sterile compounding introduction. Results: Of the 98 second-year student pharmacists, 19 consented to the study with 7 in the VR group and 12 controls. Student knowledge increased from 6.33 (0.8) to 8 (1.2) for the VR group and 7 (0.7) to 8 (0.7) for the control group. Performance for the classroom activity was 23.71 (0.3) for the VR group and 22.96 (0.9) for the control group. The NASA TLX values demonstrated positive findings for the VR experience. Conclusion: With the limited study enrollment, comparative analysis between standard materials and the VR 360 video could not be determined. This article describes the creation of a VR sterile compounding 360 video with excerpts included. Future studies to compare traditional materials to VR will be completed in the future.

Grid-based artificial bee colony algorithm for multi-objective job shop scheduling with manual loading and unloading tasks

This paper investigates a multi-objective job shop scheduling problem with manual loading and unloading tasks (MOJSSPLU) aiming to minimize makespan and total workload simultaneously. Taking human factors into consideration achieves a better balance between production efficiency and resource utilization. To address this problem, we first establish a bi-objective mixed-integer linear programming (MILP) model. Afterward, we combine the artificial bee colony algorithm with the grid technique to develop a grid-based artificial bee colony algorithm (GABC) for solving MOJSSPLU. The algorithm uses a decomposition approach with the earliest-shortest dispatching rule to reduce the complexity of MOJSSPLU. A grid coordinate system is constructed to divide the objective space into cells, facilitating individuals’ location and evaluation in the decision space. Moreover, we focus on improving the cooperation between the employed and onlooker bees and design a mathematical formula based on priority weights to generate onlooker bees to maximize information utilization and improve the exploration and exploitation capabilities of the algorithm. To ensure that the most promising individuals are retained and protected from being eliminated during the evolutionary, we propose an elitist non-dominated solutions reservation strategy for improving the diversity of the population. We further propose a dynamic adjustment of the grid-division method that focuses on improving the exploitation capacity of the algorithm in the objective space to enhance the diversity and convergence of the population. To test the performance of the GABC algorithm, we compare it to the MILP approach and other algorithms using modified benchmark instances. Furthermore, we conduct the Friedman and Wilcoxon nonparametric tests to validate the comparison results among the different algorithms. The computational results demonstrate that the algorithm GABC is efficient.

Asymptomatic Autonomic Dysregulation after Recovery from Mild COVID-19 Infection Revealed by Analysis of Heart Rate Variability Responses to Task Load.

(1) Background: The coronavirus disease 2019 (COVID-19) infection is often followed by various complications, which can cause disturbances in daily life after recovery from the infectious state, although etiological mechanisms are not fully elucidated. Previous studies have indicated that autonomic dysregulation is an underlying factor, and it is of interest to clarify whether autonomic dysregulation is also present in the asymptomatic subjects after COVID-19 infection (post-COVID-19) for early detection of post-COVID-19 complications. (2) Methods: In the present study, autonomic activity was assessed using heart rate variability (HRV) analysis in the workers who recovered from mild COVID-19 infection (n = 39). They took a leave of absence for an average of 11.9 days and returned to the original work without complications. HRV was measured after an average of 9.3 days from return. High-frequency (HF) and low-frequency (LF) HRV parameters and heart rate (HR) were recorded during a three-behavioral-state paradigm of approximately 5 min length composed of initial rest, task load, and post-task rest periods and were compared with the data of the workers without the history of COVID-19 infection (normal, n = 38). (3) Results: The HRV and HR scores at the initial rest in the post-COVID-19 subjects showed no difference from those in the control. It is found that the post-COVID-19 subjects exhibited an attenuation of LF/HF increment during the task load and an excessive increase of HF together with a decrease of LF, LF/HF and HR during the post-task rest period in comparison with the initial rest scores. (4) Conclusions: These abnormalities are evaluated as asymptomatic autonomic dysregulation in response to task load, are frequently present after COVID-19 infection, and could be related to the generation of complications.

Human-robot interactions with an autonomous health screening robot in long-term care settings

Socially assistive robots are increasingly being considered to help address the shortage of care workers in long-term care, which has been further exacerbated by the COVID-19 pandemic. In this paper, we present the first human-robot interaction study with care staff and an autonomous screening socially assistive robot in a long-term care facility. We assessed: (1) overall perceptions, experiences and attitudes of care staff prior to and after interacting with the robot, and (2) perceived workload and usability of the robot by administrators and management staff. Results show staff had overall high ratings of the robot, with a statistically significant increase identified for cognitive attitude towards the robot after interaction. Furthermore, we found that overall, perceived workload was moderately low as defined by the NASA Task Load Index while using the robot screener, and the usability rating of the robot was rated between OK and Good by the System Usability Scale. Personalization of the robot was found to be an important factor for usability. Staff enjoyed using the robot and had high willingness to frequently use it. In general, our robot study motivates the application of autonomous socially assistive robots from the staff perspective for repetitive tasks in long-term care homes.

The relationship between mental workload and nurse stress levels in hospitals

High mental workload implies significant mental resources and can lead to increased cognitive stress and fatigue. Nurses have the responsibility of managing a wide range of nursing care tasks, which frequently involve addressing anxiety, handling patient complaints, and managing patient defense mechanisms, all of which can lead to increased stress levels. This study aimed to identify the relationship between mental workload and the stress level of nurses in the Hospital Malang City. The research utilized a cross-sectional study design. The sampling technique employed was Total Sampling, involving 96 inpatient nurses at the hospital. Data collection involved the use of two questionnaires: the National Aeronautics and Space Administration Task Load Index (NASA-TLX) and the Perceived Stress Scale (PSS-10). Data analysis in this study was conducted using Pearson Correlation. The results indicated a positive relationship between mental workload and nurses' stress levels, supported by a significant p-value of 0.002 and a correlation coefficient of 0.312. A high mental workload can impact the level of job-related stress experienced by nurses. Effective stress management skills can help individuals mitigate this impact.

Distinct age-related brain activity patterns in the prefrontal cortex when increasing cognitive load: A functional near-infrared spectroscopy study

Researchers have long observed distinct brain activity patterns in older adults compared with younger adults that correlate with cognitive performance. Mainly, older adults tend to show over-recruitment of bilateral brain regions during lower task loads and improved performance interpreted as compensation, but not observed at higher loads. However, there are discrepancies about whether increases in activity are compensatory and whether older adults can show compensation at higher loads. Our aim was to examine age-related differences in prefrontal cortex (PFC) activity and cognitive performance using functional near-infrared spectroscopy (fNIRS) during single and dual N-back tasks. Twenty-seven young adults (18–27 years) and 31 older adults (64–84 yrs) took part in the study. We used a robust fNIRS data methodology consisting of channel and region of interest analyses. Results showed differences in performance between task load conditions and age-related differences in reaction times but no age-group effects for accuracy. Older adults exhibited more bilateral PFC activation compared with young adults across all tasks and showed increases in brain activity in high compared to low load conditions. Our findings further support previous reports showing that older adults use compensatory recruitment of additional brain regions in PFC to maintain cognitive performance but go against the notion that such compensation is not present at higher cognitive loads. Additionally, our results indicate that fNIRS is a sensitive tool that can characterize adaptive cortical changes in healthy aging.

Intraoperative gaze guidance with mixed reality.

Efficient communication and collaboration are essential in the operating room for successful and safe surgery. While many technologies are improving various aspects of surgery, communication between attending surgeons, residents, and surgical teams is still limited to verbal interactions that are prone to misunderstandings. Novel modes of communication can increase speed and accuracy, and transform operating rooms. A mixed reality (MR) based gaze sharing application on Microsoft HoloLens 2 headset that can help expert surgeons indicate specific regions, communicate with decreased verbal effort, and guide novices throughout an operation is presented. The utility of the application is tested with a user study of endoscopic kidney stone localization completed by urology experts and novice surgeons. Improvement is observed in the NASA task load index surveys (up to 25.23%), in the success rate of the task (6.98% increase in localized stone percentage), and in gaze analyses (up to 31.99%). The proposed application shows promise in both operating room applications and surgical trainingtasks.

Effortless Polite Telepresence using Intention Recognition

Telepresence technology creates the opportunity for people that were traditionally left out of the workforce to work remotely. In the service industry, a pool of novice remote workers could teleoperate robots to perform short work stints to fill in the gaps left by the dwindling workforce. A hurdle is that consistently talking appropriately and politely imposes a severe mental burden on such novice operators and the quality of the service may suffer. In this study, we propose a teleoperation support system that lets novice remote workers talk freely without considering appropriateness and politeness while maintaining the quality of the service. The proposed system exploits intent recognition to transform casual utterances into predefined appropriate and polite utterances. We conducted a within subject user study where 23 participants played the role of novice remote operators controlling a guardsman robot in charge of monitoring customers’ behaviors. We measured the workload with and without using the proposed support system using NASA task load index questionnaires. The workload was significantly lower ( p &lt;.001) when using the proposed support system ( M = 46.07, SD = 14.36) than when not using it ( M = 62.74, SD = 12.70). The effect size was large (Cohen’s d = 1.23).

Wound Healing and Special Considerations for the Professional and Performing Voice

Purpose: The purpose of this article is to review the wound healing process of the vocal fold following phonomicrosurgery to remove benign vocal fold lesions in professional voice users. Understanding this process and the risk of developing scar tissue at the injury site is important for treatment of these individuals. This review also highlights special considerations during the postinjury rehabilitation period and the unique vocal loading tasks and needs of performing voice users. The goal of this article is to provide clinical tools for wound healing education to nonvoice-specialized speech-language pathologists to inform their rehabilitation of the professional and performing voice user. Conclusions: Implications intrinsic to vocal fold physiology and the stages of wound healing necessitate the avoidance of scar tissue with a rehabilitation plan tailored to the unique vocal loading demands of professional and performing voice users. There is a need to develop specific rehabilitation protocols that are genre-specific to aid in the individual treatment of the elite vocal athlete.

Enhancing experience: Investigating the impact of different personal perspectives in virtual reality with lower limb rehabilitation robots on participants' motivation, experience, and engagement

Combining virtual reality (VR) with rehabilitation robots has the potential to enhance rehabilitation training and neural functional recovery. However, there is limited research on designing VR scenes and evaluating the impact of such systems on participants' cognitive and experiential aspects when using rehabilitation robots. This study aimed to examine the effects of different gaming modes (first-person perspective and third-person perspective) and robot involvement on participants' motivation, experience, task load, and engagement. Thirty-two participants underwent gait rehabilitation training, providing feedback on their experiences after each condition. The findings revealed that the first-person perspective mode increased motivation, experience, task performance, and engagement. On the other hand, robot-assisted participation improved motivation but decreased the overall experience. These results indicate that the first-person perspective mode takes precedence over the third-person perspective mode in terms of embodied gaming and the development of rehabilitation tasks.

Comparison of short-term outcomes of robotic-assisted radical colon cancer surgery using the Kangduo Surgical Robotic System and the Da Vinci Si Robotic System: a prospective cohort study.

Robotic surgery has been a revolution for colon cancer (CC) patients, with the increasing availability of different competitive robotic systems, but evidence of relevant oncologic outcomes is indeed scarce. Our goal was to compare the surgical quality and short-term oncologic outcomes of the Kangduo Surgical Robotic System and the da Vinci Si Robotic System in patients with CC. These are results from a subcohort of a multicenter randomized controlled noninferiority trial performed in three centers in China. Enrolled patients were randomly assigned to undergo surgery using either the KD-SR-01 system (KD group) or the da Vinci Si (DV) robotic system (DV group). Neither investigators nor patients were masked to treatment allocation, but assessment of pathological outcomes was masked to treatment allocation. The primary endpoint was surgical success rate. The secondary endpoints were surgical outcomes, pathologic outcomes, and postoperative outcomes. The study is registered at www.chictr.org.cn (ChiCTR2200063172). Although the long-term follow-up results were not a predefined endpoint for this study, late-stage work is in progress. A total of 58 CC patients were included in this study, 28 in the KD group and 30 in the DV group. All patients were successfully operated without any intermediate open/conventional laparoscopic surgery and the success rate of surgery was 100%. Assessment of equipment docking task load and intraoperative operating sensation score were similar between the two groups. Adverse events and Clavien-Dindo grade II or higher grade complication rates were comparable between the two groups. Device arm docking time, robotic arm operation time, and intraoperative bleeding were not significantly different between the two groups. Similar results were obtained from postoperative pathological outcomes and internal environment indexes. The efficacy and safety of the Kangduo Robotic Surgical System has been proved, operation of the Kangduo Robotic System by experienced surgeons for CC is not less effective than the da Vinci robotic System.