scholarly journals Testing silicone digit extensions as a way to suppress natural sensation to evaluate supplementary tactile feedback

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0256753
Author(s):  
Leonard F. Engels ◽  
Leonardo Cappello ◽  
Anke Fischer ◽  
Christian Cipriani
Keyword(s):  
Subjective Experience ◽  
Sensory Neuropathy ◽  
Tactile Feedback ◽  
Human Hand ◽  
Audio Feedback ◽  
Task Load ◽  
Functional Benefit ◽  
Nasa Task Load Index ◽  
And Control ◽  
Lift Task

Dexterous use of the hands depends critically on sensory feedback, so it is generally agreed that functional supplementary feedback would greatly improve the use of hand prostheses. Much research still focuses on improving non-invasive feedback that could potentially become available to all prosthesis users. However, few studies on supplementary tactile feedback for hand prostheses demonstrated a functional benefit. We suggest that confounding factors impede accurate assessment of feedback, e.g., testing non-amputee participants that inevitably focus intently on learning EMG control, the EMG’s susceptibility to noise and delays, and the limited dexterity of hand prostheses. In an attempt to assess the effect of feedback free from these constraints, we used silicone digit extensions to suppress natural tactile feedback from the fingertips and thus used the tactile feedback-deprived human hand as an approximation of an ideal feed-forward tool. Our non-amputee participants wore the extensions and performed a simple pick-and-lift task with known weight, followed by a more difficult pick-and-lift task with changing weight. They then repeated these tasks with one of three kinds of audio feedback. The tests were repeated over three days. We also conducted a similar experiment on a person with severe sensory neuropathy to test the feedback without the extensions. Furthermore, we used a questionnaire based on the NASA Task Load Index to gauge the subjective experience. Unexpectedly, we did not find any meaningful differences between the feedback groups, neither in the objective nor the subjective measurements. It is possible that the digit extensions did not fully suppress sensation, but since the participant with impaired sensation also did not improve with the supplementary feedback, we conclude that the feedback failed to provide relevant grasping information in our experiments. The study highlights the complex interaction between task, feedback variable, feedback delivery, and control, which seemingly rendered even rich, high-bandwidth acoustic feedback redundant, despite substantial sensory impairment.

scholarly journals Ageing drivers’ mental workload in real-time driving tasks based on subjective and objective measures

2021 ◽  
Vol 9 (3B) ◽  
Author(s):  
Nurul Izzah Abd Rahman ◽  
◽  
Siti Zawiah Md Dawal ◽  
Nukman Yusoff ◽  
◽  
...  
Keyword(s):  
Mental Workload ◽  
Control Group ◽  
Complex Situation ◽  
The Road ◽  
Task Load ◽  
Significant Difference ◽  
Nasa Tlx ◽  
On The Road ◽  
Nasa Task Load Index ◽  
And Control

The ageing drivers’ population is increasing rapidly, and they are exposed to disabilities due to degenerative processes, thus affecting their driving performance. The main objective of this study is to determine the mental workload of ageing drivers, while the second objective is to compare the mental workload between ageing drivers and control group. The methodology consisted of on-the-road experimental driving tasks that comprised three levels of situation complexity. The NASA-Task Load Index (NASA-TLX) and electroencephalogram (EEG) were measured on 30 drivers. The NASA-TLX scores revealed that the ageing drivers’ mean physical demand score was the highest compared to others in moderately complex situation and very complex situation, scoring 37.25 and 43.50, respectively. Meanwhile, for electroencephalogram signals’ fluctuation, results showed that situation complexity had significant effects on RPθ and RPα of channel locations FZPZ and O1O2. There was a significant difference in the weighted workload scores for the ageing drivers and control group in simple situation, while there was no significant difference found in RPθ and RPα bands at all channel locations. The findings would be beneficial as a guideline for designers, manufacturers, developers, and policy makers in designing better driving environment for ageing drivers.

scholarly journals Desktop lighting for comfortable use of a computer screen

Work ◽  
2021 ◽  
Vol 68 (s1) ◽  
pp. S209-S221
Author(s):  
Lu Han ◽  
Hechen Zhang ◽  
Zhongxia Xiang ◽  
Jinze Shang ◽  
Shabila Anjani ◽  
...  
Keyword(s):  
High Intensity ◽  
Motion Tracking ◽  
Tracking System ◽  
Computer User ◽  
Eye Tracker ◽  
Computer Screen ◽  
Task Load ◽  
Trunk Movements ◽  
Motion Tracking System ◽  
Nasa Task Load Index

BACKGROUND: The contrast between a bright computer screen and a dark ambient environment may influence comfort of the users, especially on their eyes. OBJECTIVE: The objective of this research is to identify the optimal desktop lighting for the comfortable use of the computer screen in a dark environment. METHODS: An experiment was designed where seven illumination setups were introduced for the users to perform their leisure tasks on a computer screen. Fifteen healthy subjects participated in the experiments. During each session, durations of the eye blinks, fixations and saccades of the user were recorded by an eye tracker. His/her neck and trunk movements were recorded by a motion tracking system as well. The comfort/discomfort questionnaire, localized postural discomfort questionnaire, NASA task load index and computer user questionnaire were used to record the overall comfort/discomfort, the local perceived physical discomfort, the cognitive workload, and general/eye health problems, respectively. RESULTS: Subjective and objective measurement results indicated that users felt more comfortable with high intensity warm lights using a computer screen. We also identified that the eye fixation durations, as well as the scores of two questions in the computer user questionnaire, have significant negative correlations with comfort. On the other side, the durations of blinks and the scores of three questions in the computer user questionnaire, were significantly correlated with discomfort. CONCLUSION: The warm (3000K) and high intensity (1500 lux) light reduced the visual and cognitive fatigue of the user and therefore improve the comfort of the user during the use of a computer screen.

Neural Correspondence to Human Cognition from Analysis to Intuition – Implications of Display Design for Cognition

2017 ◽  
Vol 61 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Joseph K. Nuamah ◽  
Younho Seong
Keyword(s):  
Objective Measure ◽  
Mental Effort ◽  
Human Cognition ◽  
Behavioral Measures ◽  
Display Design ◽  
Percent Correct ◽  
Task Load ◽  
Frontal Midline Theta ◽  
General Difference ◽  
Nasa Task Load Index

Psychophysiological measures can be used to determine whether a particular display produces a general difference in brain function. Such information might be valuable in efforts to improve usability in display design. In this preliminary study, we aimed to use the electroencephalography (EEG) task load index (TLI), given by the ratio of mean frontal midline theta energy to mean parietal alpha energy, to provide insight into the mental effort required by participants performing intuition-inducing and analysis-inducing tasks. We employed behavioral measures (reaction time and percent correct), and a subjective measure (NASA-Task Load Index) to validate the objective measure (TLI). The results we obtained were consistent with our hypothesis that mental effort required for analysis-inducing tasks would be different from that required for intuition-inducing tasks. Although our sample size was small, we were able to obtain a significant positive correlation between NASA-Task Load Index and TLI.

Verbal Cues and Attentional Focus: A Simulated Target-Shooting Experiment

2017 ◽  
Vol 5 (1) ◽  
pp. 148-159 ◽  
Author(s):  
Louisa D. Raisbeck ◽  
Jed A. Diekfuss
Keyword(s):  
Attentional Focus ◽  
Focus Of Attention ◽  
Verbal Cues ◽  
Task Load ◽  
External Focus ◽  
Gun Barrel ◽  
Internal Focus ◽  
And Performance ◽  
Nasa Task Load Index ◽  
Learning And Performance

Performance benefits exist for an external focus of attention compared with an internal focus of attention for performance and learning (Wulf, 2013). It is unknown, however, if varying the number of verbal cues affects learning and performance. Focus of attention and the number of verbal cues were manipulated during a simulated handgun-shooting task. For the internal focus conditions, participants were told to focus on their hand, arm, and wrist, whereas the external focus instructions were to focus on the gun, gun barrel, and gun stock. To manipulate the number of verbal cues, participants received instruction to focus on a single verbal cue or multiple verbal cues. Shooting performance was assessed at baseline, acquisition, and at two separate retention phases (immediate, delayed) that included transfer tests. Participants completed the NASA—Task Load Index to assess workload following all trials. Participants who received one verbal cue performed significantly better during immediate retention than those who received three verbal cues. Participants who used external focus of attention instructions had higher performance and reported less workload at delayed retention compared to those who used internal focus instructions. This research provides further support for the benefits of an external focus and highlights the importance of minimizing the number of verbal cues.

scholarly journals What if I had a third arm? An EEG study of a supernumerary BCI system

2019 ◽  
Author(s):  
Jaime A. Riascos ◽  
David Steeven Villa ◽  
Anderson Maciel ◽  
Luciana Nedel ◽  
Dante Barone
Keyword(s):  
Motor Imagery ◽  
Body Parts ◽  
Task Load ◽  
The Third ◽  
Person Perspective ◽  
Human Ability ◽  
Robotic Prosthesis ◽  
And Control ◽  
Bci System ◽  
Psychological Experiments

AbstractMotor imagery Brain-Computer Interface (MI-BCI) enables bodyless communication by means of the imagination of body movements. Since its apparition, MI-BCI has been widely used in applications such as guiding a robotic prosthesis, or the navigation in games and virtual reality (VR) environments. Although psychological experiments, such as the Rubber Hand Illusion - RHI, suggest the human ability for creating body transfer illusions, MI-BCI only uses the imagination of real body parts as neurofeedback training and control commands. The present work studies and explores the inclusion of an imaginary third arm as a part of the control commands for MI-BCI systems. It also compares the effectiveness of using the conventional arrows and fixation cross as training step (Graz condition) against realistic human hands performing the corresponding tasks from a first-person perspective (Hands condition); both conditions wearing a VR headset. Ten healthy subjects participated in a two-session EEG experiment involving open-close hand tasks, including a third arm that comes out from the chest. The EEG analysis shows a strong power decrease in the sensory-motor areas for the third arm task in both training conditions. Such activity is significantly stronger for Hands than Graz condition, suggesting that the realistic scenario can reduce the abstractness of the third arm and improve the generation of motor imagery signals. The cognitive load is also assessed both by NASA-TLX and Task Load index.

scholarly journals Design and evaluation of UAV ground control station by considering human factors standards and guidelines

2021 ◽  
Author(s):  
Taiwo Amida
Keyword(s):  
Human Factors ◽  
Human Error ◽  
Ground Control ◽  
Task Load ◽  
Ground Control Station ◽  
Programming Techniques ◽  
Aerial Vehicle ◽  
Standards And Guidelines ◽  
Commercial Off The Shelf ◽  
Nasa Task Load Index

The majority of Unmanned Aerial Vehicle (UAV) accidents can be directly related to human error. For this reason, standards and guidelines focusing on human factors have been published by various organizations such as Transport Canada, FAA, EASA, NASA and military agencies. The objective of this thesis is to present a methodology for designing a Ground Control Station (GCS) using available standards and guidelines for human factors. During the design process, a detailed analysis was performed using human factors methods to ensure all requirements were met; each phase of the design follows the guidelines presented in the compiled human factors standards and guidelines. The GCS interface was developed using advanced programming techniques and commercial off-the-shelf software. Moreover, an operator workload evaluation was carried out using NASA task load index for validation of design methodology. It was found that the applied methodology not only improved the pilot workload, but also ensured that all user and stakeholders’ requirements are met.

scholarly journals 3D visualization in otosurgery

2020 ◽  
Vol 19 (6) ◽  
pp. 38-49
Author(s):  
D. M. Kuz’min ◽  
◽  
A. A. Fedotova ◽  
Keyword(s):  
Middle Ear ◽  
3D Visualization ◽  
Research Work ◽  
Three Dimensional ◽  
Middle Ear Surgery ◽  
Ear Surgery ◽  
Task Load ◽  
Additional Information ◽  
Surgical Field ◽  
Nasa Task Load Index

The main priority of middle ear surgery is to create a safe and optimal view of the surgical field, as well as the most accurate visualization of anatomical structures, which is a driving factor in the evolution of otosurgery. The additional information provided by three-dimensional (3D) images has been proven to improve understanding of the temporal bone anatomy and improve the operator’s ability to assess associated diseases, thereby optimizing surgical management. In the presented experimental research work, a new technique for visualizing the surgical field is described, which improves the quality of the operator’s work and expands the possibilities of middle ear surgery. On the basis of the Chair of Otorhinolaryngology of the Mechnikov North-Western State Medical University a remote adapter for an endoscopic tube was created, which allows you to broadcast the video image received from its distal end to virtual reality glasses. For a detailed understanding of the principle of information transmission in a new three-dimensional reality, we used concepts such as disparity and stereopsis. All research results were evaluated according to the NASA Task Load Index scale. Analyzing the results of the experiment, in the conditions of three-dimensional visualization of the surgical field, a lower level of subjective workload was revealed, which was regarded as a positive effect of the realization of the phenomenon of stereopsis, when performing manipulations on the middle ear.

scholarly journals The Michelangelo Effect: Art Improves the Performance in a Virtual Reality Task Developed for Upper Limb Neurorehabilitation

2021 ◽  
Vol 11 ◽  
Author(s):  
Marco Iosa ◽  
Merve Aydin ◽  
Carolina Candelise ◽  
Natascia Coda ◽  
Giovanni Morone ◽  
...  
Keyword(s):  
Virtual Reality ◽  
User Satisfaction ◽  
Cognitive Abilities ◽  
Healthy Subjects ◽  
Aesthetic Experience ◽  
Motor Task ◽  
Mozart Effect ◽  
Task Load ◽  
Creative Art ◽  
Nasa Task Load Index

The vision of an art masterpiece is associated with brain arousal by neural processes occurring quite spontaneously in the viewer. This aesthetic experience may even elicit a response in the motor areas of the observers. In the neurorehabilitation of patients with stroke, art observation has been used for reducing psychological disorders, and creative art therapy for enhancing physical functions and cognitive abilities. Here, we developed a virtual reality task which allows patients, by moving their hand on a virtual canvas, to have the illusion of painting some art masterpieces, such as The Creation of Adam of Michelangelo or The birth of Venus of Botticelli. Twenty healthy subjects (experiment 1) and four patients with stroke (experiment 2) performed this task and a control one in which they simply colored the virtual canvas. Results from User Satisfaction Evaluation Questionnaire and the NASA Task Load Index highlighted an appropriate level of usability. Moreover, despite the motor task was the same for art and control stimuli, the art condition was performed by healthy subjects with shorter trajectories (p = 0.001) and with a lower perception of physical demand (p = 0.049). In experiment 2, only the patients treated with artistic stimuli showed a reduction in the erroneous movements performed orthogonally to the canvas (p < 0.05). This finding reminds the so-called Mozart effect that improves the performance of subjects when they listen to classic music. Thus, we called this improvement in the performance when interacting with an artistic stimulus as Michelangelo effect.

Perceived Mental Workload in an Endocopic Surgery Simulator

2005 ◽  
Vol 49 (11) ◽  
pp. 1014-1018 ◽  
Author(s):  
Martina I. Klein ◽  
Michael A. Riley ◽  
Joel S. Warm ◽  
Gerald Matthews
Keyword(s):  
Endoscopic Surgery ◽  
Mental Workload ◽  
Depth Information ◽  
Target Tissue ◽  
Task Load ◽  
Normal Hand ◽  
Multiple Resource ◽  
Nasa Task Load Index ◽  
Surgery Simulator ◽  
Experimental Effort

Endoscopic surgery–a procedure wherein a target organ is displayed on a monitor and physicians use graspers to manipulate the tissue - has benefits for patients in terms of reduced blood loss, infection, and pain. However, physicians' informal reports indicate that this type of surgery is challenging to perform. These challenges arise from the need to view the target tissue on a monitor, resulting in reduced depth information as well as a disruption of the normal hand-eye mapping. This study represents the initial experimental effort to assess the workload demands experienced in an endoscopic surgery simulator using the NASA-Task Load Index (TLX), a well validated workload measure, and the Multiple Resource Questionnaire (MRQ), a newly developed workload scale. The TLX revealed that the workload experienced in the simulator was indeed high. Additionally, the MRQ revealed different workload profiles associated with different levels of handeye mapping disruption.

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