Human FactorsPub Date : 2024-11-01Epub Date: 2023-12-06DOI: 10.1177/00187208231218196
Florestan Wagenblast, Thomas Läubli, Robert Seibt, Monika A Rieger, Benjamin Steinhilber
{"title":"Wrist Extensor Muscle Fatigue During a Dual Task With Two Muscular and Cognitive Load Levels in Younger and Older Adults.","authors":"Florestan Wagenblast, Thomas Läubli, Robert Seibt, Monika A Rieger, Benjamin Steinhilber","doi":"10.1177/00187208231218196","DOIUrl":"10.1177/00187208231218196","url":null,"abstract":"<p><strong>Objective: </strong>To examine the effect of concurrent physical and cognitive demands as well as age on indicators of muscle fatigue at the wrist.</p><p><strong>Background: </strong>There are few studies examining risk indicators for musculoskeletal disorders associated with work-related physical and cognitive demands that often occur simultaneously in the workplace.</p><p><strong>Methods: </strong>Twenty-four gender-balanced older and 24 gender-balanced younger (mean age 60 and 23 years) participants performed four 30 min dual tasks. Tasks differed by the muscular load level during force tracking: 5% and 10% of maximum voluntary contraction force (MVC) and concurrent cognitive demands on the working memory: easy and difficult. Muscle fatigue was assessed by MVC decline and changes in surface electromyography (increased root mean square: RMS, decreased median frequency: MF) at the extensor digitorum (ED) and extensor carpi ulnaris (EU).</p><p><strong>Results: </strong>A decline in MVC was found in all participants when tracking was performed at 10% MVC (mean ± SD: 137.9 ± 49.2 - 123.0 ± 45.3 N). Irrespective of age, muscular, or cognitive load, RMS increased (ED 12.3 ± 6.5 - 14.1 ± 7.0% MVE, EU 15.4 ± 7.6 - 16.9 ± 8.6% MVE) and MF decreased (ED 85.4 ± 13.6 - 83.2 ± 12.8 Hz, EU 107.2 ± 17.1 - 104.3 ± 16.7 Hz) in both muscles. However, changes in MF of EU tended to be more pronounced in the older group at higher cognitive and lower muscular load, without reaching statistical significance.</p><p><strong>Conclusion: </strong>Maximum voluntary contraction indicated no interaction between muscle fatigue, cognitive load, or age. However, the tendencies toward altered muscle activity due to an increase in cognitive load and older age suggest muscular adaptations while maintaining tracking performance during the onset of fatigue signs in the sEMG signal.</p><p><strong>Application: </strong>If the tendencies in muscle activity are confirmed by further studies, ergonomic assessments in industrial workplaces should consider cognitive load and age when describing the risk of musculoskeletal disorders.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2433-2450"},"PeriodicalIF":2.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11453032/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138500274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-11-01Epub Date: 2024-01-03DOI: 10.1177/00187208231222399
Sungho Oh, Elaine Sang, Michael A Stawnychy, Patrik Garren, Sang Bin You, Melissa O'Connor, Karen B Hirschman, Nancy Hodgson, Teresa Cranston, Juliane Jablonski, Karen O'Brien, Michael Newcomb, Melissa Spahr, Kathryn H Bowles
{"title":"Application of a Human Factors and Systems Engineering Approach to Explore Care Transitions of Sepsis Survivors From Hospital to Home Health Care.","authors":"Sungho Oh, Elaine Sang, Michael A Stawnychy, Patrik Garren, Sang Bin You, Melissa O'Connor, Karen B Hirschman, Nancy Hodgson, Teresa Cranston, Juliane Jablonski, Karen O'Brien, Michael Newcomb, Melissa Spahr, Kathryn H Bowles","doi":"10.1177/00187208231222399","DOIUrl":"10.1177/00187208231222399","url":null,"abstract":"<p><strong>Study aim: </strong>This study aims to describe the transition-in-care work process for sepsis survivors going from hospitals to home health care (HHC) and identify facilitators and barriers to enable practice change and safe care transitions using a human factors and systems engineering approach.</p><p><strong>Background: </strong>Despite high readmission risk for sepsis survivors, the transition-in-care work process from hospitals to HHC has not been described.</p><p><strong>Methods: </strong>We analyzed semi-structured needs assessment interviews with 24 stakeholders involved in transitioning sepsis survivors from two hospitals and one affiliated HHC agency participating in the parent implementation science study, I-TRANSFER. The qualitative data analysis was guided by the Systems Engineering Initiative for Patient Safety (SEIPS) framework to describe the work process and identify work system elements.</p><p><strong>Results: </strong>We identified 31 tasks characterized as decision making, patient education, communication, information, documentation, and scheduling tasks. Technological and organizational facilitators lacked in HHC compared to the hospitals. Person and organization elements in HHC had the most barriers but few facilitators. Additionally, we identified specific task barriers that could hinder sepsis information transfer from hospitals to HHC.</p><p><strong>Conclusion: </strong>This study explored the complex transition-in-care work processes for sepsis survivors going from hospitals to HHC. We identified barriers, facilitators, and critical areas for improvement to enable implementation and ensure safe care transitions. A key finding was the sepsis information transfer deficit, highlighting a critical issue for future study.</p><p><strong>Application: </strong>We recommend using the SEIPS framework to explore complex healthcare work processes before the implementation of evidence-based interventions.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2468-2484"},"PeriodicalIF":2.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139089532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-11-01Epub Date: 2023-12-05DOI: 10.1177/00187208231219184
Yusuke Yamani, Jeffrey Glassman, Abdalziz Alruwaili, Sarah E Yahoodik, Emily Davis, Samantha Lugo, Kun Xie, Sherif Ishak
{"title":"Post Take-Over Performance Varies in Drivers of Automated and Connected Vehicle Technology in Near-Miss Scenarios.","authors":"Yusuke Yamani, Jeffrey Glassman, Abdalziz Alruwaili, Sarah E Yahoodik, Emily Davis, Samantha Lugo, Kun Xie, Sherif Ishak","doi":"10.1177/00187208231219184","DOIUrl":"10.1177/00187208231219184","url":null,"abstract":"<p><strong>Objective: </strong>This study examined the impact of monitoring instructions when using an automated driving system (ADS) and road obstructions on post take-over performance in near-miss scenarios.</p><p><strong>Background: </strong>Past research indicates partial ADS reduces the driver's situation awareness and degrades post take-over performance. Connected vehicle technology may alert drivers to impending hazards in time to safely avoid near-miss events.</p><p><strong>Method: </strong>Forty-eight licensed drivers using ADS were randomly assigned to either the active driving or passive driving condition. Participants navigated eight scenarios with or without a visual obstruction in a distributed driving simulator. The experimenter drove the other simulated vehicle to manually cause near-miss events. Participants' mean longitudinal velocity, standard deviation of longitudinal velocity, and mean longitudinal acceleration were measured.</p><p><strong>Results: </strong>Participants in passive ADS group showed greater, and more variable, deceleration rates than those in the active ADS group. Despite a reliable audiovisual warning, participants failed to slow down in the red-light running scenario when the conflict vehicle was occluded. Participant's trust in the automated driving system did not vary between the beginning and end of the experiment.</p><p><strong>Conclusion: </strong>Drivers interacting with ADS in a passive manner may continue to show increased and more variable deceleration rates in near-miss scenarios even with reliable connected vehicle technology. Future research may focus on interactive effects of automated and connected driving technologies on drivers' ability to anticipate and safely navigate near-miss scenarios.</p><p><strong>Application: </strong>Designers of automated and connected vehicle technologies may consider different timing and types of cues to inform the drivers of imminent hazard in high-risk scenarios for near-miss events.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2503-2517"},"PeriodicalIF":2.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138489239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-11-01Epub Date: 2023-12-02DOI: 10.1177/00187208231218156
Owen B J Carter, Shayne Loft, Troy A W Visser
{"title":"Meaningful Communication but not Superficial Anthropomorphism Facilitates Human-Automation Trust Calibration: The Human-Automation Trust Expectation Model (HATEM).","authors":"Owen B J Carter, Shayne Loft, Troy A W Visser","doi":"10.1177/00187208231218156","DOIUrl":"10.1177/00187208231218156","url":null,"abstract":"<p><strong>Objective: </strong>The objective was to demonstrate anthropomorphism needs to communicate contextually useful information to increase user confidence and accurately calibrate human trust in automation.</p><p><strong>Background: </strong>Anthropomorphism is believed to improve human-automation trust but supporting evidence remains equivocal. We test the Human-Automation Trust Expectation Model (HATEM) that predicts improvements to trust calibration and confidence in accepted advice arising from anthropomorphism will be weak unless it aids naturalistic communication of contextually useful information to facilitate prediction of automation failures.</p><p><strong>Method: </strong>Ninety-eight undergraduates used a submarine periscope simulator to classify ships, aided by the Ship Automated Modelling (SAM) system that was 50% reliable. A between-subjects 2 × 3 design compared SAM <i>appearance</i> (anthropomorphic avatar vs. camera eye) and voice <i>inflection</i> (monotone vs. meaningless vs. meaningful), with the <i>meaningful</i> inflections communicating contextually useful information about automated advice regarding certainty and uncertainty.</p><p><strong>Results: </strong><i>Avatar</i> SAM appearance was rated as more anthropomorphic than camera <i>eye</i>, and <i>meaningless</i> and <i>meaningful</i> inflections were both rated more anthropomorphic than <i>monotone</i>. However, for subjective trust, trust calibration, and confidence in accepting SAM advice, there was no evidence of anthropomorphic appearance having any impact, while there was decisive evidence that <i>meaningful</i> inflections yielded better outcomes on these trust measures than <i>monotone</i> and <i>meaningless</i> inflections.</p><p><strong>Conclusion: </strong>Anthropomorphism had negligible impact on human-automation trust unless its execution enhanced communication of relevant information that allowed participants to better calibrate expectations of automation performance.</p><p><strong>Application: </strong>Designers using anthropomorphism to calibrate trust need to consider what contextually useful information will be communicated via anthropomorphic features.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2485-2502"},"PeriodicalIF":2.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11457490/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138471326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-10-01Epub Date: 2023-11-10DOI: 10.1177/00187208231211842
Mike Fray, Kermit G Davis
{"title":"Effectiveness of Safe Patient Handling Equipment and Techniques: A Review of Biomechanical Studies.","authors":"Mike Fray, Kermit G Davis","doi":"10.1177/00187208231211842","DOIUrl":"10.1177/00187208231211842","url":null,"abstract":"<p><strong>Objective: </strong>This review aimed to evaluate all studies that have evaluated the biomechanical effects when using assistive devices.</p><p><strong>Introduction: </strong>The physical demands of patient handling activities are well known. One safety strategy for the reduction of the physical risks is use of assistive devices.</p><p><strong>Method: </strong>The search process identified articles published in English-speaking journals through Google Scholar, Medline, and ISI Web of Science. The included 56 studies contained a biomechanical assessment of a patient handling activity with assistive devices.</p><p><strong>Results: </strong>The biomechanical effects included four groups: changes in body posture (spinal, other joints), subjective assessment (force, effort, discomfort), measured force (hand force, ground reaction force, spine force, joint torque), and physiological measures. The evidence showed caregivers benefited from using lift hoists, air-assisted devices, and to a lesser extent friction reducing devices for lateral transfers and repositioning, while floor and ceiling lifts were most effective for patient transfers. Some gaps were noted in the evidence and other handling tasks such as sit-to-stand, turning patient in bed, limb lifting, and repositioning and some more high hazard activities like supporting people with limited balance and those that fall need to be investigated with respect to biomechanical outcomes.</p><p><strong>Conclusion: </strong>There is a growing level of biomechanical evidence to support the use of assistive devices for many patient-handling tasks, but the benefits of equipment use in some transfers remain uninvestigated.</p><p><strong>Practical application: </strong>Evidence indicates the best way to lift patients safely is with floor or ceiling lifts, and air-assisted devices for lateral and repositioning tasks.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2283-2322"},"PeriodicalIF":2.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11382441/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72016301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-10-01Epub Date: 2023-11-28DOI: 10.1177/00187208231214216
Christopher A J Vine, Oliver R Runswick, Sam D Blacker, Sarah L Coakley, Andrew G Siddall, Stephen D Myers
{"title":"Cognitive, Psychophysiological, and Perceptual Responses to a Repeated Military-Specific Load Carriage Treadmill Simulation.","authors":"Christopher A J Vine, Oliver R Runswick, Sam D Blacker, Sarah L Coakley, Andrew G Siddall, Stephen D Myers","doi":"10.1177/00187208231214216","DOIUrl":"10.1177/00187208231214216","url":null,"abstract":"<p><strong>Background: </strong>Dismounted military operations require soldiers to complete cognitive tasks whilst undertaking demanding and repeated physical taskings.</p><p><strong>Objective: </strong>To assess the effects of repeated fast load carriage bouts on cognitive performance, perceptual responses, and psychophysiological markers.</p><p><strong>Methods: </strong>Twelve civilian males (age, 28 ± 8 y; stature, 186 ± 6 cm; body mass 84.3 ± 11.1 kg; V̇O<sub>2max</sub>, 51.5 ± 6.4 mL·kg<sup>-1</sup>·min<sup>-1</sup>) completed three ∼65-min bouts of a Fast Load Carriage Protocol (FLCP), each interspersed with a 65-min recovery period, carrying a representative combat load of 25 kg. During each FLCP, cognitive function was assessed using a Shoot/Don't-Shoot Task (SDST) and a Military-Specific Auditory N-Back Task (MSANT), along with subjective ratings. Additional psychophysiological markers (heart rate variability, salivary cortisol, and dehydroepiandrosterone-sulfate concentrations) were also measured.</p><p><strong>Results: </strong>A main effect of bout on MSANT combined score metric (<i>p</i> < .001, Kendall's W = 69.084) and for time on the accuracy-speed trade-off parameter of the SDST (<i>p</i> = .025, Ѡ<sup>2</sup> = .024) was evident. These likely changes in cognitive performance were coupled with subjective data indicating that participants perceived that they increased their mental effort to maintain cognitive performance (bout: <i>p</i> < .001, Ѡ<sup>2</sup> = .045; time: <i>p</i> < .001, Ѡ<sup>2</sup> = .232). Changes in HRV and salivary markers were also evident, likely tracking increased stress.</p><p><strong>Conclusion: </strong>Despite the increase in physiological and psychological stress, cognitive performance was largely maintained; purportedly a result of increased mental effort.</p><p><strong>Application: </strong>Given the likely increase in dual-task interference in the field environment compared with the laboratory, military commanders should seek approaches to manage cognitive load where possible, to maintain soldier performance.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2379-2392"},"PeriodicalIF":2.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11382434/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138453221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-10-01Epub Date: 2023-11-14DOI: 10.1177/00187208231210145
Ryan Kenny, Baruch Fischhoff, Alex Davis, Casey Canfield
{"title":"Improving Social Bot Detection Through Aid and Training.","authors":"Ryan Kenny, Baruch Fischhoff, Alex Davis, Casey Canfield","doi":"10.1177/00187208231210145","DOIUrl":"10.1177/00187208231210145","url":null,"abstract":"<p><strong>Objective: </strong>We test the effects of three aids on individuals' ability to detect social bots among Twitter personas: a bot indicator score, a training video, and a warning.</p><p><strong>Background: </strong>Detecting social bots can prevent online deception. We use a simulated social media task to evaluate three aids.</p><p><strong>Method: </strong>Lay participants judged whether each of 60 Twitter personas was a human or social bot in a simulated online environment, using agreement between three machine learning algorithms to estimate the probability of each persona being a bot. Experiment 1 compared a control group and two intervention groups, one provided a bot indicator score for each tweet; the other provided a warning about social bots. Experiment 2 compared a control group and two intervention groups, one receiving the bot indicator scores and the other a training video, focused on heuristics for identifying social bots.</p><p><strong>Results: </strong>The bot indicator score intervention improved predictive performance and reduced overconfidence in both experiments. The training video was also effective, although somewhat less so. The warning had no effect. Participants rarely reported willingness to share content for a persona that they labeled as a bot, even when they agreed with it.</p><p><strong>Conclusions: </strong>Informative interventions improved social bot detection; warning alone did not.</p><p><strong>Application: </strong>We offer an experimental testbed and methodology that can be used to evaluate and refine interventions designed to reduce vulnerability to social bots. We show the value of two interventions that could be applied in many settings.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2323-2344"},"PeriodicalIF":2.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11382440/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"107592962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-10-01Epub Date: 2023-11-30DOI: 10.1177/00187208231209137
Brandon S Thompson, Kichol Lee, John G Casali, Kara M Cave
{"title":"Development and Human Factors Evaluation of a Portable Auditory Localization Training System.","authors":"Brandon S Thompson, Kichol Lee, John G Casali, Kara M Cave","doi":"10.1177/00187208231209137","DOIUrl":"10.1177/00187208231209137","url":null,"abstract":"<p><strong>Objective: </strong>To design and develop a Portable Auditory Localization Acclimation Training (PALAT) system capable of producing psychoacoustically accurate localization cues; evaluate the training effect against a proven full-scale, laboratory-grade system under three listening conditions; and determine if the PALAT system is sensitive to differences among electronic level-dependent hearing protection devices (HPDs).</p><p><strong>Background: </strong>In-laboratory auditory localization training has demonstrated the ability to improve localization performance with the open (natural) ear, that is, unoccluded, and while wearing HPDs. The military requires a portable system capable of imparting similar training benefits as those demonstrated in laboratory experiments.</p><p><strong>Method: </strong>In a full-factorial repeated measures design experiment, 12 audiometrically normal participants completed localization training and testing using an identical, optimized training protocol on two training systems under three listening conditions (open ear, TEP-100, and ComTac™ III). Statistical tests were performed on mean absolute accuracy score and front-back reversal errors.</p><p><strong>Results: </strong>No statistical difference existed between the PALAT and laboratory-grade DRILCOM systems on two dependent localization accuracy measurements at all stages of training. In addition, the PALAT system detected the same localization performance differences among the three listening conditions.</p><p><strong>Conclusion: </strong>The PALAT system imparted similar training benefits as the DRILCOM system and was sensitive to HPD localization performance differences.</p><p><strong>Application: </strong>The user-operable PALAT system and optimized training protocol can be employed by the military, law enforcement, and various industries, to improve auditory localization performance in conditions where auditory situation awareness is critical to safety.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2393-2408"},"PeriodicalIF":2.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138464685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Changes in Neck and Shoulder Muscles Fatigue Threshold When Using a Passive Head/Neck Supporting Exoskeleton During Repetitive Overhead Tasks.","authors":"Ehsan Garosi, Zeinab Kazemi, Adel Mazloumi, Ahmadreza Keihani","doi":"10.1177/00187208231213728","DOIUrl":"10.1177/00187208231213728","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to investigate the effects of a head/neck supporting exoskeleton (HNSE) on the electromyographic fatigue threshold (EMG<sub>FT</sub>) of the neck and shoulder muscles during a simulated overhead work task.</p><p><strong>Background: </strong>Overhead work is a well-known risk factor for neck and shoulder musculoskeletal disorders due to the excessive strain imposed on the muscles and joints in these regions.</p><p><strong>Method: </strong>Fourteen healthy males performed a repetitive overhead nut fastening/unfastening task to exhaustion while wearing and not wearing the HNSE at two neck extension angles (40% and 80% of neck maximum range of motion). Electromyographic signals were continuously recorded from the right and left sternocleidomastoid (SCMR, SCML), splenius capitis (SCR, SCL), upper trapezius (UTR, UTL), and anterior deltoid (ADR, ADL) muscles. The normalized electromyographic amplitude (nEMG) data was time normalized, and a bisegmental linear regression was applied to determine the muscle fatigue break point.</p><p><strong>Results: </strong>The results showed a significant increase in fatigue threshold time in the SCMR (<i>p</i> < .001), SCML (<i>p</i> = .002), and UTR (<i>p</i> = .037) muscles when the HNSE was used. However, the EMG<sub>FT</sub> times for the right and left deltoid and left trapezius muscles showed a nonsignificant reduction due to the head/neck support exoskeleton use. In addition, the neck extension angle did not reveal a significant effect on muscles' EMG<sub>FT</sub> time.</p><p><strong>Conclusion: </strong>Overall, the findings confirmed a significant delay in fatigue onset in sternocleidomastoid muscles, as measured by the electromyographic fatigue threshold. This finding suggests that the HNSE can be an effective ergonomic intervention for reducing the risk of musculoskeletal disorders in overhead workers. However, further studies are needed to investigate the effect of the HNSE at other neck extension angles and more realistic tasks to ensure the generalizability of our results.</p><p><strong>Application: </strong>The present findings emphasize the application of the fatigue onset time to evaluate the effectiveness of ergonomic interventions, including exoskeletons, which can subsequently be utilized to alleviate postural demands and reduce the risk of musculoskeletal disorders.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2269-2282"},"PeriodicalIF":2.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89720901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Human FactorsPub Date : 2024-10-01Epub Date: 2023-11-08DOI: 10.1177/00187208231210644
Savana L King, Ellen C Szubski, Richard A Tyrrell
{"title":"Road Users Fail to Appreciate the Special Optical Properties of Retroreflective Materials.","authors":"Savana L King, Ellen C Szubski, Richard A Tyrrell","doi":"10.1177/00187208231210644","DOIUrl":"10.1177/00187208231210644","url":null,"abstract":"<p><strong>Objective: </strong>To determine whether typical road users appreciate the special optical properties of retroreflective materials.</p><p><strong>Background: </strong>Retroreflective surfaces reflect light back towards the source of the illumination. All drivers benefit from retroreflective materials, as they are required on road signs, on large trailers, in lane delineation, and other traffic control devices. Retroreflective markings can also greatly enhance the conspicuity of pedestrians at night, but pedestrians typically underuse retroreflective markings. One possible reason is that pedestrians may not appreciate the special optical properties of retroreflective materials.</p><p><strong>Method: </strong>Two experiments tested whether observers could correctly predict that retroreflective materials appear remarkably bright when illuminated by a source that is aligned with the observers' eyes. Observers used a magnitude estimation procedure to predict how bright retroreflective and non-retroreflective stimuli would appear during a demonstration designed to highlight retroreflectivity. They then judged the brightness again during the demonstration.</p><p><strong>Results: </strong>In general, observers underestimated how bright retroreflective stimuli would be and overestimated how bright diffuse reflective and fluorescent stimuli would be. The underestimates for retroreflective stimuli were particularly striking when the observers had not closely examined the stimuli in advance.</p><p><strong>Conclusion: </strong>The fact that road users do not appreciate retroreflectivity may help explain why pedestrians underuse retroreflective markings at night.</p><p><strong>Application: </strong>Educational interventions could prove useful in this domain.</p>","PeriodicalId":56333,"journal":{"name":"Human Factors","volume":" ","pages":"2409-2427"},"PeriodicalIF":2.9,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71523530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}