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Ruby P, Evangelista E, Bastuji H, Peter-Derex L. From physiological awakening to pathological sleep inertia: Neurophysiological and behavioural characteristics of the sleep-to-wake transition. Neurophysiol Clin 2024; 54:102934. [PMID: 38394921 DOI: 10.1016/j.neucli.2023.102934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 02/25/2024] Open
Abstract
Sleep inertia refers to the transient physiological state of hypoarousal upon awakening, associated with various degrees of impaired neurobehavioral performance, confusion, a desire to return to sleep and often a negative emotional state. Scalp and intracranial electro-encephalography as well as functional imaging studies have provided evidence that the sleep inertia phenomenon is underpinned by an heterogenous cerebral state mixing local sleep and local wake patterns of activity, at the neuronal and network levels. Sleep inertia is modulated by homeostasis and circadian processes, sleep stage upon awakening, and individual factors; this translates into a huge variability in its intensity even under physiological conditions. In sleep disorders, especially in hypersomnolence disorders such as idiopathic hypersomnia, sleep inertia may be a daily, serious and long-lasting symptom leading to severe impairment. To date, few tools have been developed to assess sleep inertia in clinical practice. They include mainly questionnaires and behavioral tests such as the psychomotor vigilance task. Only one neurophysiological protocol has been evaluated in hypersomnia, the forced awakening test which is based on an event-related potentials paradigm upon awakening. This contrasts with the major functional consequences of sleep inertia and its potentially dangerous consequences in subjects required to perform safety-critical tasks soon after awakening. There is a great need to identify reproducible biomarkers correlated with sleep inertia-associated cognitive and behavioral impairment. These biomarkers will aim at better understanding and measuring sleep inertia in physiological and pathological conditions, as well as objectively evaluating wake-promoting treatments or non-pharmacological countermeasures to reduce this phenomenon.
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Affiliation(s)
- Perrine Ruby
- Lyon Neuroscience Research Centre, INSERM U1028, CNRS UMR 5292, Lyon, France
| | - Elisa Evangelista
- Sleep disorder Unit, Carémeau Hospital, Centre Hospitalo-universitaire de Nîmes, France; Institute for Neurosciences of Montpellier INM, Univ Montpellier, INSERM, Montpellier, France
| | - Hélène Bastuji
- Lyon Neuroscience Research Centre, INSERM U1028, CNRS UMR 5292, Lyon, France; Centre for Sleep Medicine and Respiratory Diseases, Croix-Rousse Hospital, Hospices Civils de Lyon, Lyon 1 University, Lyon, France
| | - Laure Peter-Derex
- Lyon Neuroscience Research Centre, INSERM U1028, CNRS UMR 5292, Lyon, France; Centre for Sleep Medicine and Respiratory Diseases, Croix-Rousse Hospital, Hospices Civils de Lyon, Lyon 1 University, Lyon, France.
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2
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Kovac K, Vincent GE, Paterson JL, Hilditch CJ, Ferguson SA. A preliminary framework for managing sleep inertia in occupational settings. SLEEP ADVANCES : A JOURNAL OF THE SLEEP RESEARCH SOCIETY 2023; 4:zpad050. [PMID: 38046222 PMCID: PMC10693319 DOI: 10.1093/sleepadvances/zpad050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 10/26/2023] [Indexed: 12/05/2023]
Abstract
Sleep inertia, the temporary period of impairment experienced upon waking, is a safety hazard that has been implicated in serious work-related incidents resulting in injuries as well as the loss of life and assets. As such, sleep inertia warrants formal management in industries where personnel are required to undertake their role soon after waking (e.g. emergency services, engineers, and health care). At present, there is a lack of practical, evidence-based guidance on how sleep inertia could be formally managed at an organizational level. We propose a preliminary framework for managing sleep inertia based on the translation of research findings into specific work procedure modifications/control mechanisms. Within the framework, work procedure modifications/control mechanisms to manage sleep inertia are organized into three levels: (1) modifications/controls that eliminate the chance of sleep inertia, (2) modifications/controls that reduce sleep inertia severity, and (3) modifications/controls that manage the risk of errors during sleep inertia. Practical considerations, limitations, and areas of further research are highlighted for each modification/control to help determine how readily each control measure could be implemented by industries at present. A guide for organizations to use this preliminary framework of sleep inertia management is put forward, as well as the next research priorities to strengthen the utility and evidence base of the framework. This paper is part of the Sleep and Circadian Rhythms: Management of Fatigue in Occupational Settings Collection.
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Affiliation(s)
- Katya Kovac
- School of Health, Medical and Applied Sciences, Appleton Institute, Central Queensland University, Wayville, SA, Australia
| | - Grace E Vincent
- School of Health, Medical and Applied Sciences, Appleton Institute, Central Queensland University, Wayville, SA, Australia
| | - Jessica L Paterson
- Flinders University Institute of Mental Health and Wellbeing, College of Education, Psychology and Social Work, Flinders University, Bedford Park, SA, Australia
| | - Cassie J Hilditch
- Fatigue Countermeasures Laboratory, San José State University, San José, CA, USA
| | - Sally A Ferguson
- School of Health, Medical and Applied Sciences, Appleton Institute, Central Queensland University, Wayville, SA, Australia
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3
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LaGoy AD, Kubala AG, Deering S, Germain A, Markwald RR. Dawn of a New Dawn: Advances in Sleep Health to Optimize Performance. Sleep Med Clin 2023; 18:361-371. [PMID: 37532375 DOI: 10.1016/j.jsmc.2023.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/04/2023]
Abstract
Optimal sleep health is a critical component to high-level performance. In populations such as the military, public service (eg, firefighters), and health care, achieving optimal sleep health is difficult and subsequently deficiencies in sleep health may lead to performance decrements. However, advances in sleep monitoring technologies and mitigation strategies for poor sleep health show promise for further ecological scientific investigation within these populations. The current review briefly outlines the relationship between sleep health and performance as well as current advances in behavioral and technological approaches to improving sleep health for performance.
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Affiliation(s)
- Alice D LaGoy
- Sleep, Tactical Efficiency, and Endurance Laboratory, Warfighter Performance Department, Naval Health Research Center, 140 Sylvester Road, San Diego, CA 92106, USA; Leidos, Inc., San Diego, CA, USA
| | - Andrew G Kubala
- Sleep, Tactical Efficiency, and Endurance Laboratory, Warfighter Performance Department, Naval Health Research Center, 140 Sylvester Road, San Diego, CA 92106, USA; Leidos, Inc., San Diego, CA, USA
| | - Sean Deering
- Sleep, Tactical Efficiency, and Endurance Laboratory, Warfighter Performance Department, Naval Health Research Center, 140 Sylvester Road, San Diego, CA 92106, USA; Leidos, Inc., San Diego, CA, USA
| | | | - Rachel R Markwald
- Sleep, Tactical Efficiency, and Endurance Laboratory, Warfighter Performance Department, Naval Health Research Center, 140 Sylvester Road, San Diego, CA 92106, USA.
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4
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Arafa A, Eshak ES, Shirai K, Muraki I, Tamakoshi A, Iso H. Daytime napping and risk of liver cancer: A large population-based prospective cohort study. Ann Hepatol 2023; 28:100877. [PMID: 36423862 DOI: 10.1016/j.aohep.2022.100877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/20/2022] [Accepted: 10/31/2022] [Indexed: 11/23/2022]
Abstract
INTRODUCTION AND OBJECTIVES Liver cancer is a major cause of morbidity and mortality in Japan and worldwide. Daytime napping is a common behavior, especially among older adults, that was related in previous research to unfavorable health conditions. Herein, we investigated the association between daytime napping and liver cancer risk. MATERIALS AND METHODS In this prospective cohort study, data from 51,185 participants aged 40-79 years and registered in the Japan Collaborative Cohort Study (JACC Study) were analyzed. Incident cases of liver cancer were diagnosed using cancer registries, hospital records, and death certificates. Daytime napping was assessed using the JACC baseline self-administered questionnaire. We used the Cox regression to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of incident liver cancer among participants in the age categories of the 40s, 50s, 60s, and 70s who reported daytime napping compared with their counterparts who did not. RESULTS Within 669,734 person-years of follow-up, 341 participants developed liver cancer. Daytime napping was associated with a higher risk of liver cancer among participants who were in their 60s and 70s of age after adjusting for sex: HRs (95% CIs) 1.88 (1.35-2.61) and 1.96 (1.18-3.26), lifestyle and medical history: 1.76 (1.27-2.47) and 1.82 (1.07-3.09), and history of liver diseases: 1.66 (1.18-2.34) and 1.72 (1.01-2.94), respectively. No associations were detected among participants from the 40s and 50s age groups. CONCLUSIONS Daytime napping was associated with a higher risk of liver cancer among older adults.
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Affiliation(s)
- Ahmed Arafa
- Public Health, Department of Social Medicine, Osaka University Graduate School of Medicine, Suita, Japan; Department of Public Health, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt
| | - Ehab S Eshak
- Department of Public Health, Faculty of Medicine, Minia University, Minia, Egypt; Advanced Clinical Epidemiology, Medical Data Science, Osaka University Graduate School of Medicine, Suita, Japan; Public Health, School of Health, Calvin University, Michigan, USA
| | - Kokoro Shirai
- Public Health, Department of Social Medicine, Osaka University Graduate School of Medicine, Suita, Japan
| | - Isao Muraki
- Public Health, Department of Social Medicine, Osaka University Graduate School of Medicine, Suita, Japan
| | - Akiko Tamakoshi
- Department of Public Health, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Hiroyasu Iso
- Public Health, Department of Social Medicine, Osaka University Graduate School of Medicine, Suita, Japan.
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5
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Hilditch CJ, Wong LR, Bathurst NG, Feick NH, Pradhan S, Santamaria A, Shattuck NL, Flynn‐Evans EE. Rise and shine: The use of polychromatic short-wavelength-enriched light to mitigate sleep inertia at night following awakening from slow-wave sleep. J Sleep Res 2022; 31:e13558. [PMID: 35102669 PMCID: PMC9787581 DOI: 10.1111/jsr.13558] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/01/2021] [Accepted: 01/14/2022] [Indexed: 12/30/2022]
Abstract
Sleep inertia is the brief period of performance impairment and reduced alertness experienced after waking, especially from slow-wave sleep. We assessed the efficacy of polychromatic short-wavelength-enriched light to improve vigilant attention, alertness and mood immediately after waking from slow-wave sleep at night. Twelve participants (six female, 23.3 ± 4.2 years) maintained an actigraphy-confirmed sleep schedule of 8.5 hr for 5 nights, and 5 hr for 1 night prior to an overnight laboratory visit. In the laboratory, participants were awakened from slow-wave sleep, and immediately exposed to either dim, red ambient light (control) or polychromatic short-wavelength-enriched light (light) for 1 hr in a randomized crossover design. They completed a 5-min Psychomotor Vigilance Task, the Karolinska Sleepiness Scale, and Visual Analogue Scales of mood at 2, 17, 32 and 47 min after waking. Following this testing period, lights were turned off and participants returned to sleep. They were awakened from their subsequent slow-wave sleep period and received the opposite condition. Compared with the control condition, participants exposed to light had fewer Psychomotor Vigilance Task lapses (χ2 [1] = 5.285, p = 0.022), reported feeling more alert (Karolinska Sleepiness Scale: F1,77 = 4.955, p = 0.029; Visual Analogue Scalealert : F1,77 = 8.226, p = 0.005), and reported improved mood (Visual Analogue Scalecheerful : F1,77 = 8.615, p = 0.004). There was no significant difference in sleep-onset latency between conditions following the testing period (t10 = 1.024, p = 0.330). Our results suggest that exposure to polychromatic short-wavelength-enriched light immediately after waking from slow-wave sleep at night may help improve vigilant attention, subjective alertness, and mood. Future studies should explore the potential mechanisms of this countermeasure and its efficacy in real-world environments.
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Affiliation(s)
- Cassie J. Hilditch
- Fatigue Countermeasures LaboratorySan José State UniversitySan JoséCaliforniaUSA
| | - Lily R. Wong
- Fatigue Countermeasures LaboratorySan José State UniversitySan JoséCaliforniaUSA
| | - Nicholas G. Bathurst
- Fatigue Countermeasures LaboratoryNASA Ames Research CenterMoffett FieldCaliforniaUSA
| | - Nathan H. Feick
- Fatigue Countermeasures LaboratorySan José State UniversitySan JoséCaliforniaUSA
| | - Sean Pradhan
- Fatigue Countermeasures LaboratorySan José State UniversitySan JoséCaliforniaUSA,School of BusinessMenlo CollegeAthertonCaliforniaUSA
| | - Amanda Santamaria
- Cognitive and Systems Neuroscience Research HubUniversity of South AustraliaMagillSouth AustraliaAustralia
| | - Nita L. Shattuck
- Operations Research DepartmentHuman Systems Integration ProgramNaval Postgraduate SchoolMontereyCaliforniaUSA
| | - Erin E. Flynn‐Evans
- Fatigue Countermeasures LaboratoryNASA Ames Research CenterMoffett FieldCaliforniaUSA
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6
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Oh KT, Ko J, Shin J, Ko M. Using Wake-Up Tasks for Morning Behavior Change: Development and Usability Study. JMIR Form Res 2022; 6:e39497. [PMID: 36129742 PMCID: PMC9529170 DOI: 10.2196/39497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 08/11/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Background
Early morning behaviors between waking up and beginning daily work can develop into productive habits. However, sleep inertia limits the level of human ability immediately after waking, lowering a person’s motivation and available time for productive morning behavior.
Objective
This study explores a design for morning behavior change using a wake-up task, a simple assignment the user needs to finish before alarm dismissal. Specifically, we set two research objectives: (1) exploring key factors that relate to morning behavior performance, including the use of wake-up tasks in an alarm app and (2) understanding the general practice of affecting morning behavior change by implementing wake-up tasks.
Methods
We designed and implemented an apparatus that provides wake-up task alarms and facilities for squat exercises. We recruited 36 participants to perform squat exercises in the early morning using the wake-up tasks for 2 weeks. First, we conducted a generalized estimating equation (GEE) analysis for the first research objective. Next, we conducted a thematic analysis of the postsurvey answers to identify key themes about morning behavior change with the wake-up tasks for the second objective.
Results
The use of wake-up tasks was significantly associated with both the completion of the target behavior (math task: P=.005; picture task: P<.001) and the elapsed time (picture task: P=.08); the time to alarm dismissal was significantly related to the elapsed time to completion (P<.001). Moreover, the theory of planned behavior (TPB) variables, common factors for behavior change, were significant, but their magnitudes and directions differed slightly from the other domains. Furthermore, the survey results reveal how the participants used the wake-up tasks and why they were effective for morning behavior performance.
Conclusions
The results reveal the effectiveness of wake-up tasks in accomplishing the target morning behavior and address key factors for morning behavior change, such as (1) waking up on time, (2) escaping from sleep inertia, and (3) quickly starting the desired target behavior.
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Affiliation(s)
- Kyue Taek Oh
- Department of Human-Computer Interaction, Hanyang University, Ansan, Republic of Korea
| | - Jisu Ko
- Department of Applied Artificial Intelligence, Hanyang University, Ansan, Republic of Korea
| | | | - Minsam Ko
- Department of Human-Computer Interaction, Hanyang University, Ansan, Republic of Korea
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7
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Toward Sustainable Gentle Awakenings and Sleep Inertia Mitigation: A Low-Cost IoT-Based Adaptable Lighting and Temperature Control Approach. SUSTAINABILITY 2022. [DOI: 10.3390/su14137928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In this paper, our design aims to assist in sleep inertia reduction and avoid the startle response and irritation caused by alarm-made unpleasant wakeup stimuli. Thus, we propose an approach that employs a soft and alerting sunrise simulation, conditionally utilizes natural light, and appropriately lowers the bedroom temperature for awakening a sleeper tenderly and gradually to gain full alertness. This approach is inspired by known scientific implications confirming the effectiveness of lights and temperatures on wakefulness. In this regard, we present an economical do-it-yourself digital tech-assisted system for bedroom lighting and temperature control. The system design is based on the smartphone and Internet of Things (IoT) technology. We develop the hardware and software in the system for implementing three IoT-based control tasks. One is the tuning of artificial light brightness using the pulse width modulation technique. Another is the opening of the window curtain using stepper motor control and light detection. The other is the activation of the air-conditioning setting using an infrared remote control and temperature detection. We construct a testbed for conducting experiments. Experimental results demonstrate that the proposed system can execute task requirements satisfactorily. The proposed system is promising for achieving our goal. It embodies features of sustainability.
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8
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C Gupta C, Dominiak M, Kovac K, C Reynolds A, A Ferguson S, J Hilditch C, Sprajcer M, E Vincent G. On-call work and sleep: the importance of switching on during a callout and switching off after a call. INDUSTRIAL HEALTH 2022; 60:91-96. [PMID: 34690251 PMCID: PMC8980688 DOI: 10.2486/indhealth.2021-0124] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 08/23/2021] [Indexed: 06/13/2023]
Abstract
Due to the unpredictable nature of working time arrangements, on-call workers experience regular disruption to sleep, particularly if woken by calls. Sleep disruption can impact long term physical and mental health, next day performance, and importantly, performance immediately after waking. To reduce the impact of performance impairments upon waking (i.e., reducing sleep inertia), research has investigated strategies to promote alertness (e.g., bright light, caffeine, and exercise). This review puts forth on-call workers who are likely to return to sleep after a call, it is also important to consider the impact of these sleep inertia countermeasures on subsequent sleep. Future research should build on the preliminary evidence base for sleep inertia countermeasures by examining the impact on subsequent sleep. This research is key for both supporting alertness and performance during a call ("switching on") and for allowing the on-call worker to return to sleep after a call ("switching off").
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Affiliation(s)
- Charlotte C Gupta
- Central Queensland University, Appleton Institute for Behavioural Science, Australia
| | - Michelle Dominiak
- Central Queensland University, Appleton Institute for Behavioural Science, Australia
| | - Katya Kovac
- Central Queensland University, Appleton Institute for Behavioural Science, Australia
| | - Amy C Reynolds
- Flinders Health and Medical Research Institute (Sleep Health), Flinders University, Australia
| | - Sally A Ferguson
- Central Queensland University, Appleton Institute for Behavioural Science, Australia
| | - Cassie J Hilditch
- San José State University, Fatigue Countermeasures Laboratory, Department of Psychology, USA
| | - Madeline Sprajcer
- Central Queensland University, Appleton Institute for Behavioural Science, Australia
| | - Grace E Vincent
- Central Queensland University, Appleton Institute for Behavioural Science, Australia
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9
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Ma Z, Chen XY, Wang D, Zhu Z, Niu H, Huang S, Zhou X, Yang Z, Fan F. Who is the hardest to wake up from sleep? An investigation of self-reported sleep inertia using a latent profile analysis. J Sleep Res 2022; 31:e13552. [PMID: 35112414 DOI: 10.1111/jsr.13552] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/02/2022] [Accepted: 01/03/2022] [Indexed: 11/30/2022]
Abstract
Few studies have assessed the overall nature and profiles of subjective sleep inertia (SI) within the general population. This study was designed to identify subjective SI profiles and examine the associations between profiles of subjective SI with sociodemographic and sleep-related characteristics. A total of 11 colleges and universities were surveyed from May 30 to June 17, 2021, by convenience sampling. A total of 1,240 participants provided usable data regarding sociodemographic information, Sleep Inertia Questionnaire, and sleep-related characteristics via an online platform. Latent profile analysis was utilised to identify profiles of SI. Multinomial logistic regression was further performed to examine the predisposing factors of profiles of SI. Four profiles of SI were identified: (1) "Low SI", 20%; (2) "Mild SI", 31%; (3) "Moderate SI", 33%; and (4) "Severe SI", 16%. Compared to a Low SI profile, younger, individuals with an evening chronotype, and individuals who had <6 h sleep/night, experienced poor sleep quality, and moderate-to-severe sleep disturbance were at increased risk of experiencing severe SI. Individuals with more languid types tended to show more severe SI, while individuals reporting greater flexibility experienced less SI. This study is the first effort to examine the profiles of subjective SI using latent profile analysis and identified four profiles of SI in the general population. This effort may contribute to a greater understanding of SI, including the development of a screening tool and interventions to reduce SI.
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Affiliation(s)
- Zijuan Ma
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
| | - Xiao-Yan Chen
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
| | - Dongfang Wang
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
| | - Zhiyi Zhu
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
| | - Haiquan Niu
- School of Psychology, Nanjing Normal University, Nanjing, China
| | - Shuiqing Huang
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
| | - Xiuzhu Zhou
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
| | - Zheng Yang
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
| | - Fang Fan
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
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10
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Kovac K, Vincent GE, Paterson JL, Ferguson SA. "I Want to Be Safe and Not Still Half Asleep": Exploring Practical Countermeasures to Manage the Risk of Sleep Inertia for Emergency Service Personnel Using a Mixed Methods Approach. Nat Sci Sleep 2022; 14:1493-1510. [PMID: 36052102 PMCID: PMC9427208 DOI: 10.2147/nss.s370488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/08/2022] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The aim of this exploratory cross-sectional mixed methods study was to determine 1) whether sleep inertia, the temporary state of impaired vigilance performance upon waking, is perceived to be a concern by emergency service personnel, 2) what strategies are currently used by emergency service workplaces to manage sleep inertia, 3) the barriers to implementing reactive sleep inertia countermeasures, and 4) what strategies personnel suggest to manage sleep inertia. PARTICIPANTS AND METHODS A sample (n = 92) of employed and volunteer Australian emergency service personnel (fire and rescue, ambulance, police, state-based rescue and recovery personnel) completed an online survey. Data collected included demographic variables and work context, experiences of sleep inertia in the emergency role, barriers to sleep inertia countermeasures, and existing workplace sleep inertia countermeasures and recommendations. Quantitative data were analysed using descriptive statistics, and qualitative data were thematically analysed. RESULTS Approximately 67% of participants expressed concern about sleep inertia when responding in their emergency role. Despite this, there were few strategies to manage sleep inertia in the workplace. One major barrier identified was a lack of time in being able to implement sleep inertia countermeasures. Fatigue management strategies, such as reducing on-call periods, and operational changes, such as screening calls to reduce false alarms, were suggested by participants as potential strategies to manage sleep inertia. CONCLUSION Sleep inertia is a concern for emergency service personnel and thus more research is required to determine effective sleep inertia management strategies to reduce the risks associated with sleep inertia and improve personnel safety and those in their care. In addition, future studies could investigate strategies to integrate reactive sleep inertia countermeasures into the emergency response procedure.
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Affiliation(s)
- Katya Kovac
- School of Health, Medical and Applied Sciences, Appleton Institute, Central Queensland University, Wayville, SA, Australia
| | - Grace E Vincent
- School of Health, Medical and Applied Sciences, Appleton Institute, Central Queensland University, Wayville, SA, Australia
| | - Jessica L Paterson
- Flinders Institute of Mental Health and Wellbeing, College of Education, Psychology and Social Work, Flinders University, Bedford Park, SA, Australia
| | - Sally A Ferguson
- School of Health, Medical and Applied Sciences, Appleton Institute, Central Queensland University, Wayville, SA, Australia
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11
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Ma Z, Tao Y, Chen H, Zhang Y, Pan Y, Meng D, Fan F. An Exploration of Self-Reported Sleep Inertia Symptoms Using Network Analysis. Nat Sci Sleep 2022; 14:661-674. [PMID: 35450224 PMCID: PMC9018210 DOI: 10.2147/nss.s347419] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 03/30/2022] [Indexed: 11/29/2022] Open
Abstract
PURPOSE Sleep inertia (SI) is the transitional state accompanied by compromised cognitive and physical performance and sleepiness. Network analysis offers a potential new framework to conceptualize a complex network of symptom-symptom interactions, and the network structure is analyzed to reveal the core characteristics. However, no previous study examined the network structure of SI symptoms. Thus, this study aimed to elucidate characteristics and compare sex differences of SI symptom networks in the general population. MATERIALS AND METHODS A total of 1491 participants from China were recruited from 30 May to 17 June, 2021. SI symptoms were assessed by using the Sleep Inertia Questionnaire (SIQ). The network structures were estimated and compared using network analytic methods in the R version 4.1.1. RESULTS Centrality properties analysis of the expected influence suggested that symptoms of "Feel sleepy", "Groggy, fuzzy or hazy mind", and "Dread starting your day" exerted greatest influences. The weighted adjacency matrix revealed that the "Dread starting your day" and "Anxious about the upcoming day" edge showed the strongest connection (edge weight value = 0.70). The network comparison test found no significant difference in network global strength (p=0.928), distribution of edge weights (p=0.194) and individual edge weights (all p values >0.05 after Holm-Bonferroni corrections) between males and females. CONCLUSION Symptoms of "Feel sleepy", "Groggy, fuzzy or hazy mind", and "Dread starting your day" were central in the SI symptom network. Intervention, such as the artificial dawn and change in body temperature, for symptoms of "Feel sleepy", "Groggy, fuzzy or hazy mind", and "Dread starting your day" might be crucial to hasten the dissipation of SI in the general population who may need to perform tasks upon waking.
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Affiliation(s)
- Zijuan Ma
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, People's Republic of China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, People's Republic of China
| | - Yanqiang Tao
- Beijing Key Laboratory of Applied Experimental Psychology, Faculty of Psychology, Beijing Normal University, Beijing, People's Republic of China
| | - Huilin Chen
- Department of Psychology, University of Bath, Bath, UK
| | - Yifan Zhang
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, People's Republic of China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, People's Republic of China
| | - Ye Pan
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, People's Republic of China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, People's Republic of China
| | - Dongjing Meng
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, People's Republic of China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, People's Republic of China
| | - Fang Fan
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, People's Republic of China.,Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, People's Republic of China
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12
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Kovac K, Vincent GE, Paterson JL, Reynolds A, Aisbett B, Hilditch CJ, Ferguson SA. The impact of a short burst of exercise on sleep inertia. Physiol Behav 2021; 242:113617. [PMID: 34606883 DOI: 10.1016/j.physbeh.2021.113617] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 09/16/2021] [Accepted: 09/29/2021] [Indexed: 11/18/2022]
Abstract
STUDY OBJECTIVES Determine whether 30 s (s) of exercise performed upon waking can reduce sleep inertia and accelerate an increase in the cortisol awakening response (CAR) and core body temperature (CBT), compared to when sedentary. METHODS Fifteen participants (mean age ± SD, 25.9 ± 5.9 years; six females) completed a counterbalanced, repeated measures, in-laboratory study involving three single experimental nights, each separated by a four-night recovery period. Participants were woken following a 2-h nap (2400-0200) and completed a cycling bout of high-intensity (30-s sprint), low-intensity (30 s at 60% maximum heart rate), or no exercise (sedentary). Sleep inertia testing (eight batteries, 15-min intervals) began immediately following and included measures of subjective sleepiness (Karolinska Sleepiness Scale) and cognitive performance tasks (psychomotor vigilance, serial addition and subtraction, and spatial configuration). CBT was measured continuously via an ingestible telemetric capsule. The CAR was determined using salivary cortisol samples collected at 0, 30 and 45 min post-waking. Data were analysed using mixed effects analysis of variance. RESULTS There was no difference in cognitive performance or CBT between conditions. Participants felt less sleepy in the high-intensity condition, followed by the low-intensity and sedentary conditions (p = .003). The CAR was greatest in the high-intensity condition, followed by the sedentary condition, and low-intensity condition (p < 0.001), with no differences between the low-intensity and sedentary conditions. CONCLUSIONS Those who exercise upon waking should be aware that while they may feel more alert, they may not be performing better than if they had not exercised. Future research should investigate whether exercise of different duration or timing may impact sleep inertia.
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Affiliation(s)
- Katya Kovac
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia.
| | - Grace E Vincent
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
| | - Jessica L Paterson
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
| | - Amy Reynolds
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
| | - Brad Aisbett
- Deakin University, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Geelong, Victoria, Australia
| | - Cassie J Hilditch
- Fatigue Countermeasures Laboratory, San José State University, San José, CA, USA
| | - Sally A Ferguson
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
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13
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Gurubhagavatula I, Barger LK, Barnes CM, Basner M, Boivin DB, Dawson D, Drake CL, Flynn-Evans EE, Mysliwiec V, Patterson PD, Reid KJ, Samuels C, Shattuck NL, Kazmi U, Carandang G, Heald JL, Van Dongen HP. Guiding principles for determining work shift duration and addressing the effects of work shift duration on performance, safety, and health: guidance from the American Academy of Sleep Medicine and the Sleep Research Society. J Clin Sleep Med 2021; 17:2283-2306. [PMID: 34666885 PMCID: PMC8636361 DOI: 10.5664/jcsm.9512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 06/24/2021] [Indexed: 11/13/2022]
Abstract
CITATION Risks associated with fatigue that accumulates during work shifts have historically been managed through working time arrangements that specify fixed maximum durations of work shifts and minimum durations of time off. By themselves, such arrangements are not sufficient to curb risks to performance, safety, and health caused by misalignment between work schedules and the biological regulation of waking alertness and sleep. Science-based approaches for determining shift duration and mitigating associated risks, while addressing operational needs, require: (1) a recognition of the factors contributing to fatigue and fatigue-related risks; (2) an understanding of evidence-based countermeasures that may reduce fatigue and/or fatigue-related risks; and (3) an informed approach to selecting workplace-specific strategies for managing work hours. We propose a series of guiding principles to assist stakeholders with designing a shift duration decision-making process that effectively balances the need to meet operational demands with the need to manage fatigue-related risks.
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Affiliation(s)
- Indira Gurubhagavatula
- Division of Sleep Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
| | - Laura K. Barger
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Christopher M. Barnes
- Department of Management and Organization, Foster School of Business, University of Washington, Seattle, WA, USA
| | - Mathias Basner
- Unit for Experimental Psychiatry, Division of Sleep and Chronobiology, Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Diane B. Boivin
- Centre for Study and Treatment of Circadian Rhythms, Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Drew Dawson
- Appleton Institute, Central Queensland University, Wayville, SA, Australia
| | | | - Erin E. Flynn-Evans
- Fatigue Countermeasures Laboratory, NASA Ames Research Center, Moffett Field, CA, USA
| | - Vincent Mysliwiec
- STRONG STAR ORU, Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center, San Antonio, TX, USA
| | - P. Daniel Patterson
- Department of Emergency Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kathryn J. Reid
- Center for Circadian and Sleep Medicine, Department of Neurology, Division of Sleep Medicine, Northwestern University, Chicago, IL, USA
| | - Charles Samuels
- Centre for Sleep and Human Performance, Calgary, Alberta, Canada
| | - Nita Lewis Shattuck
- Operations Research Department, Naval Postgraduate School, Monterey, CA, USA
| | - Uzma Kazmi
- American Academy of Sleep Medicine, Darien, IL, USA
| | | | | | - Hans P.A. Van Dongen
- Sleep and Performance Research Center, Washington State University, Spokane, WA, USA
- Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, USA
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14
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A novel bedtime pulsatile-release caffeine formula ameliorates sleep inertia symptoms immediately upon awakening. Sci Rep 2021; 11:19734. [PMID: 34611208 PMCID: PMC8492773 DOI: 10.1038/s41598-021-98376-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 08/30/2021] [Indexed: 02/08/2023] Open
Abstract
Sleep inertia is a disabling state of grogginess and impaired vigilance immediately upon awakening. The adenosine receptor antagonist, caffeine, is widely used to reduce sleep inertia symptoms, yet the initial, most severe impairments are hardly alleviated by post-awakening caffeine intake. To ameliorate this disabling state more potently, we developed an innovative, delayed, pulsatile-release caffeine formulation targeting an efficacious dose briefly before planned awakening. We comprehensively tested this formulation in two separate studies. First, we established the in vivo caffeine release profile in 10 young men. Subsequently, we investigated in placebo-controlled, double-blind, cross-over fashion the formulation's ability to improve sleep inertia in 22 sleep-restricted volunteers. Following oral administration of 160 mg caffeine at 22:30, we kept volunteers awake until 03:00, to increase sleep inertia symptoms upon scheduled awakening at 07:00. Immediately upon awakening, we quantified subjective state, psychomotor vigilance, cognitive performance, and followed the evolution of the cortisol awakening response. We also recorded standard polysomnography during nocturnal sleep and a 1-h nap opportunity at 08:00. Compared to placebo, the engineered caffeine formula accelerated the reaction time on the psychomotor vigilance task, increased positive and reduced negative affect scores, improved sleep inertia ratings, prolonged the cortisol awakening response, and delayed nap sleep latency one hour after scheduled awakening. Based on these findings, we conclude that this novel, pulsatile-release caffeine formulation facilitates the sleep-to-wake transition in sleep-restricted healthy adults. We propose that individuals suffering from disabling sleep inertia may benefit from this innovative approach.Trials registration: NCT04975360.
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15
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Gurubhagavatula I, Barger LK, Barnes CM, Basner M, Boivin DB, Dawson D, Drake CL, Flynn-Evans EE, Mysliwiec V, Patterson PD, Reid KJ, Samuels C, Shattuck NL, Kazmi U, Carandang G, Heald JL, Van Dongen HPA. Guiding principles for determining work shift duration and addressing the effects of work shift duration on performance, safety, and health: guidance from the American Academy of Sleep Medicine and the Sleep Research Society. Sleep 2021; 44:6312566. [PMID: 34373924 DOI: 10.1093/sleep/zsab161] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/17/2021] [Indexed: 11/12/2022] Open
Abstract
Risks associated with fatigue that accumulates during work shifts have historically been managed through working time arrangements that specify fixed maximum durations of work shifts and minimum durations of time off. By themselves, such arrangements are not sufficient to curb risks to performance, safety, and health caused by misalignment between work schedules and the biological regulation of waking alertness and sleep. Science-based approaches for determining shift duration and mitigating associated risks, while addressing operational needs, require: (1) a recognition of the factors contributing to fatigue and fatigue-related risks; (2) an understanding of evidence-based countermeasures that may reduce fatigue and/or fatigue-related risks; and (3) an informed approach to selecting workplace-specific strategies for managing work hours. We propose a series of guiding principles to assist stakeholders with designing a shift duration decision-making process that effectively balances the need to meet operational demands with the need to manage fatigue-related risks.
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Affiliation(s)
- Indira Gurubhagavatula
- Division of Sleep Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Corporal Michael Crescenz VA Medical Center, Philadelphia, PA, USA
| | - Laura K Barger
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA.,Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Christopher M Barnes
- Department of Management and Organization, Foster School of Business, University of Washington, Seattle, WA, USA
| | - Mathias Basner
- Unit for Experimental Psychiatry, Division of Sleep and Chronobiology, Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Diane B Boivin
- Centre for Study and Treatment of Circadian Rhythms, Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Drew Dawson
- Appleton Institute, Central Queensland University, Wayville, SA, Australia
| | | | - Erin E Flynn-Evans
- Fatigue Countermeasures Laboratory, NASA Ames Research Center, Moffett Field, CA, USA
| | - Vincent Mysliwiec
- STRONG STAR ORU, Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center, San Antonio, TX, USA
| | - P Daniel Patterson
- Department of Emergency Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kathryn J Reid
- Center for Circadian and Sleep Medicine, Department of Neurology, Division of Sleep Medicine, Northwestern University, Chicago, IL, USA
| | - Charles Samuels
- Centre for Sleep and Human Performance, Calgary, Alberta, Canada
| | - Nita Lewis Shattuck
- Operations Research Department, Naval Postgraduate School, Monterey, CA, USA
| | - Uzma Kazmi
- American Academy of Sleep Medicine, Darien, IL, USA
| | | | | | - Hans P A Van Dongen
- Sleep and Performance Research Center, Washington State University, Spokane, WA, USA.,Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, USA
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16
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Trait Interindividual Differences in the Magnitude of Subjective Sleepiness from Sleep Inertia. Clocks Sleep 2021; 3:298-311. [PMID: 34204864 PMCID: PMC8293243 DOI: 10.3390/clockssleep3020019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/29/2021] [Accepted: 05/31/2021] [Indexed: 01/06/2023] Open
Abstract
In shift work settings and on-call operations, workers may be at risk of sleep inertia when called to action immediately after awakening from sleep. However, individuals may differ substantially in their susceptibility to sleep inertia. We investigated this using data from a laboratory study in which 20 healthy young adults were each exposed to 36 h of total sleep deprivation, preceded by a baseline sleep period and followed by a recovery sleep period, on three separate occasions. In the week prior to each laboratory session and on the corresponding baseline night in the laboratory, participants either extended their sleep period to 12 h/day or restricted it to 6 h/day. During periods of wakefulness in the laboratory, starting right after scheduled awakening, participants completed neurobehavioral tests every 2 h. Testing included the Karolinska Sleepiness Scale to measure subjective sleepiness, for which the data were analyzed with nonlinear mixed-effects regression to quantify sleep inertia. This revealed considerable interindividual differences in the magnitude of sleep inertia, which were highly stable within individuals after both baseline and recovery sleep periods, regardless of study condition. Our results demonstrate that interindividual differences in subjective sleepiness due to sleep inertia are substantial and constitute a trait.
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17
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Abstract
Sleep inertia (SI) refers to a complex psychophysiological phenomenon, observed after awakening, that can be described as the gradual recovery of waking-like status. The time course of cognitive performance dissipation in an everyday life condition is still unclear, especially in terms of the sleep stage at awakening (REM or NREM-stage 2) and the relative effects on performance. The present study aimed to investigate the SI dissipation in different memory performances upon spontaneous morning awakening after uninterrupted nighttime sleep. Eighteen young adults (7 females; mean age 24.9 ± 3.14 years) spent seven non-consecutive nights (one baseline, three REM awakenings and three St2 awakenings) in the laboratory under standard polysomnographic (PSG) control. Participants were tested after three REM awakenings and three St2 awakenings, and three times at 11:00 a.m. as a control condition. In each testing session, participants filled in the Global Vigor and Affect Scale and carried out one memory task (episodic, semantic, or procedural task). For each condition, participants were tested every 10 min within a time window of 80 min. In accordance with previous studies, SI affected subjective alertness throughout the entire time window assessed. Moreover, SI significantly affected performance speed but not accuracy in the semantic task. With reference to this task, the SI effect dissipated within 30 min of awakening from REM, and within 20 min of awakening from St2. No significant SI effect was observed on episodic or procedural memory tasks.
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18
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Alarm Tones, Voice Warnings, and Musical Treatments: A Systematic Review of Auditory Countermeasures for Sleep Inertia in Abrupt and Casual Awakenings. Clocks Sleep 2020; 2:416-433. [PMID: 33118526 PMCID: PMC7711682 DOI: 10.3390/clockssleep2040031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/12/2020] [Accepted: 10/16/2020] [Indexed: 11/16/2022] Open
Abstract
Sleep inertia is a measurable decline in cognition some people experience upon and following awakening. However, a systematic review of the current up to date evidence of audio as a countermeasure has yet to be reported. Thus, to amend this gap in knowledge, the authors conducted this systematic review beginning with searches in three primary databases for studies published between the inception date of each journal and the year 2020. Search terms contained “Sleep Inertia” paired with: “Sound”; “Noise”; “Music”; “Alarm”; “Alarm Tone”; “Alarm Sound”; “Alarm Noise”; “Alarm Music”; “Alarm Clock”; “Fire Alarm”, and “Smoke Alarm”. From 341 study results, twelve were identified for inclusion against a priori conditions. A structured narrative synthesis approach generated three key auditory stimulus themes-(i) Noise, (ii) Emergency tone sequences; Voice Alarms and Hybrids, and (iii) Music. Across themes, participants have been assessed in two situational categories: emergency, and non-emergency awakenings. The results indicate that for children awakening in emergency conditions, a low pitch alarm or voice warnings appear to be more effective in counteracting the effects of sleep inertia than alarms with higher frequencies. For adults abruptly awakened, there is insufficient evidence to support firm conclusions regarding alarm types and voice signals. Positive results have been found in non-emergency awakenings for musical treatments in adults who preferred popular music, and alarms with melodic qualities. The results observed reflect the potential for sound, voice, and musical treatments to counteract sleep inertia post-awakening, and emphasize the requirements for further research in this domain.
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19
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Dawson D, Ferguson SA, Vincent GE. Safety implications of fatigue and sleep inertia for emergency services personnel. Sleep Med Rev 2020; 55:101386. [PMID: 33027747 DOI: 10.1016/j.smrv.2020.101386] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 12/31/2022]
Abstract
Emergency services present a unique operational environment for the management of fatigue and sleep inertia. Communities request and often expect the provision of emergency services on a 24/7/365 basis. This can result in highly variable workloads and/or significant need for on-demand or on-call working time arrangements. In turn, the management of fatigue-related risk requires a different approach than in other more predictable shift working sectors (e.g., mining and manufacturing). The aim of this review is to provide a comprehensive overview of fatigue risk management that is accessible to regulators, policy makers and organisations in the emergency services sector. The review outlines the unique fatigue challenges in the emergency services sector, examines the current scientific and policy consensus around managing fatigue and sleep inertia, and finally discusses strategies that emergency services organisations can use to minimise the risks associated with fatigue and sleep inertia.
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Affiliation(s)
- Drew Dawson
- Central Queensland University, Appleton Institute, Adelaide, South Australia, Australia.
| | - Sally A Ferguson
- Central Queensland University, Appleton Institute, Adelaide, South Australia, Australia
| | - Grace E Vincent
- Central Queensland University, Appleton Institute, Adelaide, South Australia, Australia
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20
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Liang SF, Shih YH, Hu YH, Kuo CE. A Method for Napping Time Recommendation Using Electrical Brain Activity. IEEE Trans Cogn Dev Syst 2020. [DOI: 10.1109/tcds.2020.2991176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Slyusarenko K, Fedorin I. Smart alarm based on sleep stages prediction. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:4286-4289. [PMID: 33018943 DOI: 10.1109/embc44109.2020.9176320] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A sleep inertia after waking up strongly affects the overall mental recovery after sleep. The sleep inertia depends not as much on overall sleep quality but also on the sleep stage in the waking up moment. The fix-time alarming system results in waking up at random sleep stage, which results in frequent sleep inertia. The widely used flow-time alarming systems based on motion detection (actigraphy) reduce but do not eliminate sleep inertia. Such systems do not wake up users in Deep sleep stage, but may instead wake them up in Wake, Light, or REM (Rapid Eyes Movement) stages. Moreover, frequent waking up in the REM stage results in serious psychological issues. We present a smartwatch alarm system that predicts sleep stages and thus produces an alarm call at an easy waking up moment with minimal sleep inertia effect. The sleep stages are predicted using an Encoder-Decoder Recurrent Neural Network model. The rationale of the prediction is that each sleep stages cycling pattern is a continuous quasi-periodic process. Experimental results from over 138 nocturnal sleep periods from 92 respondents show that our system provides 66-70% accuracy for Deep, Light, Wake, REM sleep stages and 71-77% accuracy for 2-classes (Deep/REM vs. Light/Wake stages) prediction classifications. The proposed alarm system wakes up the user at the moment when Easy Wake (Wake/Light) stage is the most probable.
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22
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Sleep Inertia Countermeasures in Automated Driving: A Concept of Cognitive Stimulation. INFORMATION 2020. [DOI: 10.3390/info11070342] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
When highly automated driving is realized, the role of the driver will change dramatically. Drivers will even be able to sleep during the drive. However, when awaking from sleep, drivers often experience sleep inertia, meaning they are feeling groggy and are impaired in their driving performance―which can be an issue with the concept of dual-mode vehicles that allow both manual and automated driving. Proactive methods to avoid sleep inertia like the widely applied ‘NASA nap’ are not immediately practicable in automated driving. Therefore, a reactive countermeasure, the sleep inertia counter-procedure for drivers (SICD), has been developed with the aim to activate and motivate the driver as well as to measure the driver’s alertness level. The SICD is evaluated in a study with N = 21 drivers in a level highly automation driving simulator. The SICD was able to activate the driver after sleep and was perceived as “assisting” by the drivers. It was not capable of measuring the driver’s alertness level. The interpretation of the findings is limited due to a lack of a comparative baseline condition. Future research is needed on direct comparisons of different countermeasures to sleep inertia that are effective and accepted by drivers.
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23
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McFarlane SJ, Garcia JE, Verhagen DS, Dyer AG. Auditory Countermeasures for Sleep Inertia: Exploring the Effect of Melody and Rhythm in an Ecological Context. Clocks Sleep 2020; 2:208-224. [PMID: 33089201 PMCID: PMC7445849 DOI: 10.3390/clockssleep2020017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 05/27/2020] [Indexed: 12/02/2022] Open
Abstract
Sleep inertia is a decline in cognition one may experience upon and following awakening. A recent study revealed that an alarm sound perceived as melodic by participants displayed a significant relationship to reports of reductions in perceived sleep inertia. This current research builds on these findings by testing the effect melody and rhythm exhibit on sleep inertia for subjects awakening in their habitual environments. Two test Groups (A and B; N = 10 each) completed an online psychomotor experiment and questionnaire in two separate test sessions immediately following awakening from nocturnal sleep. Both groups responded to a control stimulus in the first session, while in the second session, Group A experienced a melodic treatment, and Group B a rhythmic treatment. The results show that the melodic treatment significantly decreased attentional lapses, false starts, and had a significantly improved psychomotor vigilance test (PVT) performance score than the control. There was no significant result for reaction time or response speed. Additionally, no significant difference was observed for all PVT metrics between the control-rhythmic conditions. The results from this analysis support melodies' potential to counteract symptoms of sleep inertia by the observed increase in participant vigilance following waking from nocturnal sleep.
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Affiliation(s)
- Stuart J McFarlane
- School of Media and Communication, RMIT University, Melbourne 3001, Australia; (J.E.G.); (A.G.D.)
| | - Jair E Garcia
- School of Media and Communication, RMIT University, Melbourne 3001, Australia; (J.E.G.); (A.G.D.)
| | | | - Adrian G Dyer
- School of Media and Communication, RMIT University, Melbourne 3001, Australia; (J.E.G.); (A.G.D.)
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24
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Kovac K, Ferguson SA, Paterson JL, Aisbett B, Hilditch CJ, Reynolds AC, Vincent GE. Exercising Caution Upon Waking-Can Exercise Reduce Sleep Inertia? Front Physiol 2020; 11:254. [PMID: 32317980 PMCID: PMC7155753 DOI: 10.3389/fphys.2020.00254] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 03/05/2020] [Indexed: 11/13/2022] Open
Abstract
Sleep inertia, the transitional state of reduced alertness and impaired cognitive performance upon waking, is a safety risk for on-call personnel who can be required to perform critical tasks soon after waking. Sleep inertia countermeasures have previously been investigated; however, none have successfully dissipated sleep inertia within the first 15 min following waking. During this time, on-call personnel could already be driving, providing advice, or performing other safety-critical tasks. Exercise has not yet been investigated as a sleep inertia countermeasure but has the potential to stimulate the key physiological mechanisms that occur upon waking, including changes in cerebral blood flow, the cortisol awakening response, and increases in core body temperature. Here, we examine these physiological processes and hypothesize how exercise can stimulate them, positioning exercise as an effective sleep inertia countermeasure. We then propose key considerations for research investigating the efficacy of exercise as a sleep inertia countermeasure, including the need to determine the intensity and duration of exercise required to reduce sleep inertia, as well as testing the effectiveness of exercise across a range of conditions in which the severity of sleep inertia may vary. Finally, practical considerations are identified, including the recommendation that qualitative field-based research be conducted with on-call personnel to determine the potential constraints in utilizing exercise as a sleep inertia countermeasure in real-world scenarios.
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Affiliation(s)
- Katya Kovac
- Appleton Institute, School of Health, Medical and Applied Sciences, Central Queensland University, Adelaide, SA, Australia
| | - Sally A Ferguson
- Appleton Institute, School of Health, Medical and Applied Sciences, Central Queensland University, Adelaide, SA, Australia
| | - Jessica L Paterson
- Appleton Institute, School of Health, Medical and Applied Sciences, Central Queensland University, Adelaide, SA, Australia
| | - Brad Aisbett
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, VIC, Australia
| | - Cassie J Hilditch
- Fatigue Countermeasures Laboratory, San José State University Research Foundation, Moffett Field, CA, United States
| | - Amy C Reynolds
- Appleton Institute, School of Health, Medical and Applied Sciences, Central Queensland University, Adelaide, SA, Australia
| | - Grace E Vincent
- Appleton Institute, School of Health, Medical and Applied Sciences, Central Queensland University, Adelaide, SA, Australia
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25
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Kovac K, Vincent GE, Jay SM, Sprajcer M, Aisbett B, Lack L, Ferguson SA. The impact of anticipating a stressful task on sleep inertia when on-call. APPLIED ERGONOMICS 2020; 82:102942. [PMID: 31479838 DOI: 10.1016/j.apergo.2019.102942] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 08/20/2019] [Accepted: 08/21/2019] [Indexed: 06/10/2023]
Abstract
Sleep inertia, the state of reduced alertness upon waking, can negatively impact on-call workers. Anticipation of a stressful task on sleep inertia, while on-call was investigated. Young, healthy males (n = 23) spent an adaptation, control and two counterbalanced on-call nights in the laboratory. When on-call, participants were told they would be woken to a high or low stress task. Participants were not woken during the night, instead were given a 2300-0700 sleep opportunity. Participants slept ∼7.5-h in all conditions. Upon waking, sleep inertia was quantified using the Karolinska Sleepiness Scale and Psychomotor Vigilance and Spatial Configuration Tasks, administered at 15-min intervals. Compared to control, participants felt sleepier post waking when on-call and sleepiest in the low stress compared to the high stress condition (p < .001). Spatial performance was faster when on-call compared to control (p < .001). Findings suggest that anticipating a high-stress task when on-call, does not impact sleep inertia severity.
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Affiliation(s)
- Katya Kovac
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia.
| | - Grace E Vincent
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
| | - Sarah M Jay
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
| | - Madeline Sprajcer
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
| | - Brad Aisbett
- Deakin University, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Geelong, Australia
| | - Leon Lack
- School of Psychology, Flinders University of South Australia, Adelaide, SA, Australia
| | - Sally A Ferguson
- Central Queensland University, Appleton Institute, School of Health, Medical and Applied Sciences, Wayville, Adelaide, Australia
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Vincent GE, Sargent C, Roach GD, Miller DJ, Kovac K, Scanlan AT, Waggoner LB, Lastella M. Exercise before bed does not impact sleep inertia in young healthy males. J Sleep Res 2019; 29:e12903. [PMID: 31621995 DOI: 10.1111/jsr.12903] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 06/17/2019] [Accepted: 07/17/2019] [Indexed: 02/01/2023]
Abstract
Sleep inertia is the transitional state marked by impaired cognitive performance and reduced vigilance upon waking. Exercising before bed may increase the amount of slow-wave sleep within the sleep period, which has previously been associated with increased sleep inertia. Healthy males (n = 12) spent 3 nights in a sleep laboratory (1-night washout period between each night) and completed one of the three conditions on each visit - no exercise, aerobic exercise (30 min cycling at 75% heart rate), and resistance exercise (six resistance exercises, three sets of 10 repetitions). The exercise conditions were completed 90 min prior to bed. Sleep was measured using polysomnography. Upon waking, participants completed five test batteries every 15 min, including the Karolinska Sleepiness Scale, a Psychomotor Vigilance Task, and the Spatial Configuration Task. Two separate linear mixed-effects models were used to assess: (a) the impact of condition; and (b) the amount of slow-wave sleep, on sleep inertia. There were no significant differences in sleep inertia between conditions, likely as a result of the similar sleep amount, sleep structure and time of awakening between conditions. The amount of slow-wave sleep impacted fastest 10% reciprocal reaction time on the Psychomotor Vigilance Task only, whereby more slow-wave sleep improved performance; however, the magnitude of this relationship was small. Results from this study suggest that exercise performed 90 min before bed does not negatively impact on sleep inertia. Future studies should investigate the impact of exercise intensity, duration and timing on sleep and subsequent sleep inertia.
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Affiliation(s)
- Grace E Vincent
- Appleton Institute, Central Queensland University, Adelaide, SA, Australia
| | - Charli Sargent
- Appleton Institute, Central Queensland University, Adelaide, SA, Australia
| | - Gregory D Roach
- Appleton Institute, Central Queensland University, Adelaide, SA, Australia
| | - Dean J Miller
- Appleton Institute, Central Queensland University, Adelaide, SA, Australia
| | - Katya Kovac
- Appleton Institute, Central Queensland University, Adelaide, SA, Australia
| | - Aaron T Scanlan
- Human Exercise and Training Laboratory, Central Queensland University, Rockhampton, QLD, Australia
| | - Lauren B Waggoner
- Operational Fatigue Research, Institutes for Behavior Resources, Inc., Baltimore, MD, USA
| | - Michele Lastella
- Appleton Institute, Central Queensland University, Adelaide, SA, Australia
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Figueiro MG, Sahin L, Roohan C, Kalsher M, Plitnick B, Rea MS. Effects of red light on sleep inertia. Nat Sci Sleep 2019; 11:45-57. [PMID: 31118850 PMCID: PMC6506010 DOI: 10.2147/nss.s195563] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 03/08/2019] [Indexed: 11/23/2022] Open
Abstract
Introduction: Sleep inertia, broadly defined as decrements in performance and lowering of alertness following waking, lasts for durations ranging between 1 min and 3 hrs. This study investigated whether, compared to a dim light condition (the control), exposure to long-wavelength (red) light delivered to closed eyelids during sleep (red light mask) and to eyes open upon waking (red light goggles) reduced sleep inertia. Methods: Thirty participants (18 females, 12 males; mean age=30.4 years [SD 13.7]) completed this crossover, within-subjects, counterbalanced design study. Self-reported measures of sleepiness and objective measures of auditory performance and cortisol levels were collected on 3 Friday nights over the course of 3 consecutive weeks. Results: Performance improved significantly during the 30-min data collection period in all experimental conditions. Subjective sleepiness also decreased significantly with time awake in all experimental conditions. As hypothesized, performance of some tasks was significantly better in the red light mask condition than in the dim light condition. Performance scores in the red light goggles condition improved significantly after a few minutes of wearing the light goggles. Discussion: The results show that saturated red light delivered through closed eyelids at levels that do not suppress melatonin can be used to mitigate sleep inertia upon waking.
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Affiliation(s)
- Mariana G Figueiro
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Levent Sahin
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Charles Roohan
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Michael Kalsher
- Department of Cognitive Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Barbara Plitnick
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Mark S Rea
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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Abstract
Sleep inertia, or the grogginess felt upon awakening, is associated with significant cognitive performance decrements that dissipate as time awake increases. This impairment in cognitive performance has been observed in both tightly controlled in-laboratory studies and in real-world scenarios. Further, these decrements in performance are exaggerated by prior sleep loss and the time of day in which a person awakens. This review will examine current insights into the causes of sleep inertia, factors that may positively or negatively influence the degree of sleep inertia, the consequences of sleep inertia both in the laboratory and in real-world settings, and lastly discuss potential countermeasures to lessen the impact of sleep inertia.
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Affiliation(s)
- Cassie J Hilditch
- Fatigue Countermeasures Laboratory, San Jose State University Research Foundation, Moffett Field, San Jose, CA 94035, USA
| | - Andrew W McHill
- Oregon Institute of Occupational Health Sciences, Oregon Health and Science University, Portland, OR 97239, USA
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29
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Bérastégui P, Jaspar M, Ghuysen A, Nyssen AS. Fatigue-related risk management in the emergency department: a focus-group study. Intern Emerg Med 2018; 13:1273-1281. [PMID: 29777436 DOI: 10.1007/s11739-018-1873-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 05/06/2018] [Indexed: 11/30/2022]
Abstract
Fatigue has major implications on both patient safety and healthcare practitioner's well-being. Traditionally, two approaches can be used to reduce fatigue-related risk: reducing the likelihood of a fatigued operator working (i.e. fatigue reduction), or reducing the likelihood that a fatigued operator will make an error (i.e. fatigue proofing). Recent progress mainly focussed on fatigue reduction strategies such as reducing work hours. Yet it has to be recognized that such approach has not wholly overcome the experience of fatigue. Our purpose is to investigate individual proofing and reduction strategies used by emergency physicians to manage fatigue-related risk. 25 emergency physicians were recruited for the study. Four focus groups were formed which consisted of an average of six individuals. Qualitative data were collected using a semi-structured discussion guide unfolding in two parts. First, the participants were asked to describe how on-the-job fatigue affected their efficiency at work. A mind map was progressively drawn based upon the participants' perceived effects of fatigue. Second, participants were asked to describe any strategies they personally used to cope with these effects. We used inductive qualitative content analysis to reveal content themes for both fatigue effects and strategies. Emergency physicians reported 28 fatigue effects, 12 reduction strategies and 21 proofing strategies. Content analysis yielded a further classification of proofing strategies into self-regulation, task re-allocation and error monitoring strategies. There is significant potential for the development of more formal processes based on physicians' informal strategies.
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Affiliation(s)
- Pierre Bérastégui
- Cognitive Ergonomics Laboratory (LECIT), Department of Work Psychology, University of Liège, Sart-Tilman B31, 4000, Liege, Belgium.
| | - Mathieu Jaspar
- Cognitive Ergonomics Laboratory (LECIT), Department of Work Psychology, University of Liège, Sart-Tilman B31, 4000, Liege, Belgium
| | - Alexandre Ghuysen
- Emergency Department, University Hospital Centre of Liège, Liege, Belgium
| | - Anne-Sophie Nyssen
- Cognitive Ergonomics Laboratory (LECIT), Department of Work Psychology, University of Liège, Sart-Tilman B31, 4000, Liege, Belgium
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Centofanti S, Banks S, Colella A, Dingle C, Devine L, Galindo H, Pantelios S, Brkic G, Dorrian J. Coping with shift work-related circadian disruption: A mixed-methods case study on napping and caffeine use in Australian nurses and midwives. Chronobiol Int 2018; 35:853-864. [DOI: 10.1080/07420528.2018.1466798] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Stephanie Centofanti
- Sleep & Chronobiology Laboratory, University of South Australia, Adelaide, Australia
| | - Siobhan Banks
- Sleep & Chronobiology Laboratory, University of South Australia, Adelaide, Australia
| | | | - Caroline Dingle
- SA Health, Government of South Australia, Adelaide, Australia
| | - Lisa Devine
- SA Health, Government of South Australia, Adelaide, Australia
| | - Helen Galindo
- SA Health, Government of South Australia, Adelaide, Australia
| | | | - Gorjana Brkic
- SA Health, Government of South Australia, Adelaide, Australia
| | - Jillian Dorrian
- Sleep & Chronobiology Laboratory, University of South Australia, Adelaide, Australia
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31
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Physical-Preparation Recommendations for Elite Rugby Sevens Performance. Int J Sports Physiol Perform 2018; 13:255-267. [DOI: 10.1123/ijspp.2016-0728] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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32
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Weisgerber DM, Nikol M, Mistlberger RE. Driving home from the night shift: a bright light intervention study. Sleep Med 2017; 30:171-179. [DOI: 10.1016/j.sleep.2016.09.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 08/22/2016] [Accepted: 09/12/2016] [Indexed: 02/08/2023]
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