Publications
CamNtech Research Library
CamNtech products have been trusted by specialist researchers for 25 years. Our research library contains peer reviewed publications citing the use of our devices. Filter by product, application, keyword, author or use free text search to locate your area of interest.
pyActigraphy: open-source python package for actigraphy data visualisation and analysis
Over the past 40 years, actigraphy has been used to study rest-activity patterns in circadian rhythm and sleep research. Furthermore, considering its simplicity of use, there is a growing interest in the analysis of large population-based samples, using actigraphy. Here, we introduce pyActigraphy, a comprehensive toolbox for data visualization and analysis including multiple sleep detection […]
Related Product: MotionWatch
Publication Date: December 3, 2020
Enhancing daily light exposure increases the antibody response to influenza vaccination in patients with dementia
Enhancing lighting conditions in institutions for individuals with dementia improves their sleep, circadian rhythms and well-being. Here, we tested whether a greater long-term daily light exposure supports the immune response to the annual influenza vaccination. Eighty older institutionalised patients suffering from dementia (54 women and 26 men) continuously wore an activity tracker for 8 weeks […]
Related Product: MotionWatch
Publication Date: December 2, 2020
Sleep− wake cycle dysregulation in idiopathic REM sleep behaviour disorder
Alteration of the circadian sleep−wake rhythm has been suggested in patients affected by idiopathic rapid eye movement sleep behaviour disorder. Because actigraphy is the validated instrument to monitor the sleep−wake cycle, the aim of the present study was to investigate the circadian sleep−wake rhythm in patients with idiopathic rapid eye movement sleep behaviour disorder compared […]
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Publication Date: December 1, 2020
Taking the sleep lab to the field: Biometric techniques for quantifying sleep and circadian rhythms in humans
Objectives Remarkably, the specifics of sleep along the human lineage have been slow to emerge, which is surprising given our distinct mental and behavioral capacity and the importance of sleep for individual health and cognitive performance. Largely due to difficultly of measuring sleep outside a controlled, clinical, and laboratory study in ambulatory individuals, human biologists […]
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Publication Date: November 30, 2020
Cross-participant prediction of vigilance stages through the combined use of wPLI and wSMI EEG functional connectivity metrics
Functional connectivity (FC) metrics describe brain inter-regional interactions and may complement information provided by common power-based analyses. Here we investigated whether the FC-metrics weighted Phase Lag Index (wPLI) and weighted Symbolic Mutual Information (wSMI) may unveil functional differences across four stages of vigilance – wakefulness (W), NREM-N2, NREM-N3 and REM sleep – with respect to […]
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Publication Date: November 21, 2020
From Dawn to Dusk–Mimicking Natural Daylight Exposure Improves Circadian Rhythm Entrainment in Patients with Severe Brain Injury
Background: Better integrity of circadian rhythms has been shown to relate to a richer behavioral repertoire in patients with disorders of consciousness (DOC). As light exposure has proven successful in treating circadian rhythm disorders, we sought to investigate whether simulating natural daylight in a clinical setting can entrain circadian rhythms in patients with DOC, and […]
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Publication Date: November 2, 2020
Testing the Implementation of Function-focused Care in Assisted Living Settings
Objectives The purpose of this study was to evaluate the Function-Focused Care for Assisted Living Using the Evidence Integration Triangle (FFC-AL-EIT) intervention. Design FFC-AL-EIT was a randomized controlled pragmatic trial including 85 sites and 794 residents. Intervention FFC-AL-EIT was implemented by a Research Nurse Facilitator working with a facility champion and stakeholder team for 12 […]
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Publication Date: October 31, 2020
Objective sleep patterns and validity of self-reported sleep monitoring across different playing levels in rugby union
BACKGROUND: Growing evidence highlights that elite rugby union players experience poor sleep quality and quantity which can be detrimental for performance OBJECTIVES: This study aimed to i) compare objective sleep measures of rugby union players between age categories over a one week period, and ii) compare self-reported measures of sleep to wristwatch actigraphy as the […]
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Publication Date: October 1, 2020
Effect of vestibular stimulation using a rotatory chair in human rest/activity rhythm
The vestibular system is responsible for sensing every angular and linear head acceleration, mainly during periods of motor activity. Previous animal and human experiments have shown biological rhythm disruptions in small rodents exposed to a hypergravity environment, but also in patients with bilateral vestibular loss compared to a control population. This raised the hypothesis of […]
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Publication Date: September 26, 2020
Timed physical exercise does not influence circadian rhythms and glucose tolerance in rotating night shift workers: The EuRhythDia study
Objectives: Night shift workers are at cardiometabolic risk due to circadian misalignment. We investigated whether infrequent exercise before each night shift that intentionally would not improve physical performance improves glucose tolerance and 24-h blood pressure profiles and synchronizes circadian rhythms of melatonin and cortisol in rotating night shift workers. Methods: A total of 24 rotating […]
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Publication Date: September 25, 2020
A phase 2a randomised, double-blind, placebo-controlled, parallel-group, add-on clinical trial of ebselen (SPI-1005) as a novel treatment for mania or hypomania
Rationale Lithium is an effective prophylactic and anti-manic treatment in bipolar disorder; however, its use is declining through perceived poor tolerance and toxicity. Lithium inhibits inositol monophosphatase (IMPase), a probable key therapeutic mechanism. The anti-inflammatory drug, ebselen, also inhibits IMPase and appears well-tolerated and safe. Objectives To assess the efficacy of adjunctive ebselen in mania […]
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Publication Date: September 9, 2020
Prediction of individual differences in circadian adaptation to night work among older adults: application of a mathematical model using individual sleep-wake and light exposure data
Circadian misalignment remains a distinct challenge for night shift workers. Variability in individual sleep-wake/light-dark patterns might contribute to individual differences in circadian alignment in night shift workers. In this simulation study, we compared the predicted phase shift from a mathematical model of the effect of light on the human circadian pacemaker to the observed melatonin […]
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Publication Date: September 6, 2020
Multiple sclerosis-related fatigue: the role of impaired corticospinal responses and heightened exercise fatigability
It is unclear whether motor fatigability and perceived fatigue share a common pathophysiology in people with multiple sclerosis (PwMS). This cross-sectional investigation explored the relationship between the mechanisms of motor fatigability from cycling and fatigue severity in PwMS. Thirteen highly fatigued (HF) and thirteen non-fatigued (LF) PwMS, and thirteen healthy controls (CON) completed a step-test […]
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Publication Date: September 2, 2020
Use of actigraphy and sleep diaries to assess sleep and academic performance in pharmacy students
Introduction Sleep parameters have been shown to correlate with academic performance. Current studies assessing sleep in doctor of pharmacy (PharmD) students rely on self-reported sleep parameters and academic performance. The objectives of this study were to describe and compare sleep parameters in pharmacy students using actigraphy and sleep diaries and to assess the correlation of […]
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Publication Date: August 30, 2020
An Automatic Estimation of the Rest-Interval for MotionWatch8© Using Uniaxial Movement and Lux Data
Poor sleep is linked with chronic conditions common in older adults, including diabetes, heart disease, and dementia. Valid and reliable field methods to objectively measure sleep are thus greatly needed to examine how poor sleep impacts older adults. Wrist-worn actigraphy (WWA) is a common objective measure of sleep that uses motion and illuminance data to […]
Related Product: MotionWatch
Publication Date: August 24, 2020
Binocular Vision, Visual Function, and Pupil Dynamics in People Living With Dementia and Their Relation to the Rate of Cognitive Decline and Structural Changes Within the Brain: Protocol for an Observational Study
Background: Visual impairment is a common comorbidity in people living with dementia. Addressing sources of visual difficulties can have a significant impact on the quality of life for people living with dementia and their caregivers. Depth perception problems are purportedly common in dementia and also contribute to falls, visuomotor task difficulties, and poorer psychosocial well-being. […]
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Publication Date: August 10, 2020
Local increases in sleep-like activity predict the occurrence of emotion suppression failures
Emotion self-regulation relies both on cognitive and behavioral strategies implemented to modulate the subjective experience and/or the behavioral expression of a given emotion. While it is known that a network encompassing fronto-cingulate and parietal brain areas is engaged during successful emotion regulation, the functional mechanisms underlying failures in emotion suppression are still unclear. In order […]
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Publication Date: August 5, 2020
Reduced Neuromuscular Performance in Night Shift Orthopedic Nurses: New Insights From a Combined Electromyographic and Force Signals Approach
The effect of sleep–wake rhythm disruption on neuromuscular control and muscle fatigue has received little attention. Because nurse shift work is so varied, including overnight duty, rotating shift schedules, early awakening, and interrupted nocturnal sleep, it offers an interesting model to study this paradigm. It has been investigated so far using only subjective markers. A […]
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Publication Date: June 30, 2020
The clinical relevance of early identification and treatment of sleep disorders in mental health care: protocol of a randomized control trial
Background Sleep disorders are a risk factor for developing a variety of mental disorders, have a negative impact on their remission rates and increase the risk of relapse. Early identification and treatment of sleep disorders is therefore of paramount importance. Unfortunately, in mental health care sleep disorders are often poorly recognized and specific treatment frequently […]
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Publication Date: June 24, 2020
Disturbances of Continuous Sleep and Circadian Rhythms Account for Behavioral Difficulties in Children with Autism Spectrum Disorder
Sleep disorders are among the most common comorbidities in children with Autism Spectrum Disorder (ASD), and subjectively defined sleep disturbances have been related to ASD symptom severity. However, no study has investigated the differential impact of objectively measured sleep and circadian rhythm disturbances on behavioral difficulties in this population. Fifty-two children with ASD aged 3–10 […]
Related Product: MotionWatch
Publication Date: June 24, 2020
Using Mobile Electroencephalography and Actigraphy to Diagnose Attention-Deficit/Hyperactivity Disorder: Case-Control Comparison Study
Background: Children with attention-deficit/hyperactivity disorder (ADHD), a neurobehavioral disorder, display behaviors of inattention, hyperactivity, or impulsivity, which can affect their ability to learn and establish proper family and social relationships. Various tools are currently used by child and adolescent psychiatric clinics to diagnose, evaluate, and collect information and data. The tools allow professional physicians to […]
Related Product: MotionWatch
Publication Date: June 19, 2020
A pragmatic approach to the comparison of wrist-based cutpoints of physical activity intensity for the MotionWatch8 accelerometer in children
Background A variety of wearable monitors are available for objectively assessing physical activity but there is a lack of established values for the activity intensity of MotionWatch8 (MW8) and a similar lack of studies on comparability across devices. Our study aimed to establish activity intensity cutpoints for the MW8 accelerometer in children, which are necessary […]
Related Product: MotionWatch
Publication Date: June 19, 2020
Toward a Better Understanding of the Reciprocal Relations Between Adolescent Psychological Need Experiences and Sleep
In two diary studies, we examined the reciprocal daily association between the satisfaction and frustration of adolescents’ basic psychological needs and sleep, and the role of stress and fatigue in these associations. In Study 1 (N = 211; 52% female; Mage = 15.86 years, SD = 1.18 years), daily need experiences were unrelated to daily […]
Related Product: MotionWatch
Publication Date: June 19, 2020
Light effects on circadian and homeostatic regulation: alertness increases independent of time awake
Study Objectives To determine how sleepiness and sleep deprivation drive the motivation to engage in different behaviors. Methods We studied the sleepiness of 123 participants who had been randomized to sleep deprivation or normal sleep, and their willingness to engage in a range of everyday behaviors. Results Self-reported sleepiness was a strong predictor of the […]
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Publication Date: June 6, 2020
Early manifestation of sleep problems in toddlers with Williams Syndrome using a mixed method longitudinal approach
Children with neurodevelopmental disorders commonly experience sleep problems. Williams Syndrome (WS), a rare genetic disorder characterised by a complex, uneven cognitive profile, is no exception. Compared with children with typical development (TD), school-aged children with WS experience significant sleep disruption: shorter sleep duration, more night wakings, greater bedtime resistance and excessive daytime tiredness. In children […]
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Publication Date: June 3, 2020
Sleep duration, sleep variability, and impairments of visual attention
Attentional networks are sensitive to sleep deprivation. However, variation in attentional performance as a function of normal sleep parameters is understudied. We examined whether attentional performance is influenced by (a) individual differences in sleep duration, (b) sleep duration variability, and/or (c) their interaction. A total of 57 healthy participants (61.4% female, Mage = 32.37 years, SD = 8.68) completed questionnaires, […]
Related Product: MotionWatch
Publication Date: June 1, 2020
Rationale and Study Design of OUTSTEP‐HF: A Randomized Controlled Study to Assess the Effect of Sacubitril/Valsartan and Enalapril on Physical Activity measured by Accelerometry in Patients with Heart Failure with Reduced Ejection Fraction
Aim In PARADIGM‐HF, sacubitril/valsartan demonstrated superiority to enalapril in reducing mortality and morbidity in patients with heart failure (HF) with reduced ejection fraction (HFrEF). Several patient‐centred outcomes like improved physical activity and quality of life (QoL) have been emphasised as important therapy goals in HF management. OUTSTEP‐HF has been designed to evaluate the effects of […]
Related Product: MotionWatch
Publication Date: May 28, 2020
Gateways, Disparities, and Finals Week, Oh My! Translating Sleep Science from the Laboratory to the Classroom
Introduction Organic chemistry can be an insurmountable “gateway” course for otherwise-qualified students in pre-health pathways. Recent data indicate that organic chemistry increases drop-out risk for females and underrepresented minority students (URMs), raising the provocative possibility that sleep disparities are an underrecognized contributor to achievement gaps in gateway STEM courses. Methods In Study 1, 481 students […]
Related Product: MotionWatch
Publication Date: May 27, 2020
Subjective–objective sleep discrepancy in patients with insomnia during and after cognitive behavioural therapy: An actigraphy study
Although patients with insomnia often show a discrepancy between self‐reported and objective sleep parameters, the role of and change in this phenomenon during treatment remain unclear. The present study aimed to assess the effect of cognitive behavioural therapy for insomnia on subjective and objective sleep discrepancy of total sleep time, sleep‐onset latency and wake after […]
Related Product: MotionWatch
Publication Date: May 20, 2020
Effect of a Multimodal Lifestyle Intervention on Sleep and Cognitive Function in Older Adults with Probable Mild Cognitive Impairment and Poor Sleep: A Randomized Clinical Trial
Background:Poor sleep is common among older adults with mild cognitive impairment (MCI) and may contribute to further cognitive decline. Whether multimodal lifestyle intervention that combines bright light therapy (BLT), physical activity (PA), and good sleep hygiene can improve sleep in older adults with MCI and poor sleep is unknown. Objective:To assess the effect of a […]
Related Product: MotionWatch
Publication Date: May 19, 2020
Observation and interview-based diurnal sleepiness inventory for measurement of sleepiness in patients referred for narcolepsy or idiopathic hypersomnia
STUDY OBJECTIVES:First, to determine whether the three-item ODSI (Observation and interview based Diurnal Sleepiness Inventory) measures the degree of excessive daytime sleepiness (EDS) in patients with suspected narcolepsy or idiopathic hypersomnia (IH). Second, to assess the correlation between the ODSI and the Epworth Sleepiness Scale (ESS) as well as objective polysomnographic measurements. Third, to test […]
Related Product: MotionWatch
Publication Date: May 14, 2020
Feasibility of a complex setting for assessing sleep and circadian rhythmicity in a Fragile X cohort
Introduction Sleep, circadian rhythms, (mental) health, and development are assumed to be intertwined. However, differentiated and reliable parameters of sleep and circadian rhythms are particularly difficult to assess for Fragile X (FXS) individuals. As those parameters need to be observed in complex settings, the feasibility of measurements for people with FXS was to be proven. […]
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Publication Date: May 14, 2020
Schizophrenia-associated variation at ZNF804A correlates with altered experience-dependent dynamics of sleep slow-waves and spindles in healthy young adults
Background The rs1344706 polymorphism in ZNF804A is robustly associated with schizophrenia (SZ), yet brain and behavioral phenotypes related to this variant have not been extensively characterized. In turn, SZ is associated with abnormal non-rapid eye movement (NREM) sleep neurophysiology. To examine whether rs1344706 is associated with intermediate neurophysiological traits in the absence of disease, we […]
Related Product: MotionWatch
Publication Date: May 3, 2020
Rest-activity rhythm in breast cancer survivors: an update based on non-parametric indices
Recently we evaluated by actigraphy the rest-activity circadian rhythm (RAR) in breast cancer (BC) survivors at 5 years from primary diagnosis, as well as in a control group with similar age and body mass index (BMI). RAR, analyzed by Cosinor method, resulted significantly different in BC survivors compared to healthy subjects: BC survivors showed lower […]
Related Product: MotionWatch
Publication Date: April 24, 2020
Sleep disturbance in atopic dermatitis: a case–control study using actigraphy and smartphone‐collected questionnaires
Introduction Atopic dermatitis (AD) has a significant impact on quality of life, particularly related to sleep disorders secondary to pruritus. The aim of this study was to assess the sleep of patients with AD and compare it to that of healthy volunteers (SV) using a wrist activity monitor and a smartphone app. Material and methods […]
Related Product: MotionWatch
Publication Date: April 22, 2020
Refining sleep measurement using the Motionwatch8©: How many days of monitoring do we need to get reliable estimates of sleep quality for older adults with Mild Cognitive Impairment?
Background Mild cognitive impairment (MCI) is a transition stage between healthy cognition and dementia, and is linked to poorer sleep. Objective, reliable, and low-burden field methods to measure older adult sleep are also currently needed. The MotionWatch8© (MW8) wrist-worn actigraph provides estimates of sleep with 14 days of observation; however, there may be underlying differences […]
Related Product: MotionWatch
Publication Date: April 3, 2020
Fractal biomarker of activity in patients with bipolar disorder
Background The output of many healthy physiological systems displays fractal fluctuations with self-similar temporal structures. Altered fractal patterns are associated with pathological conditions. There is evidence that patients with bipolar disorder have altered daily behaviors. Methods To test whether fractal patterns in motor activity are altered in patients with bipolar disorder, we analyzed 2-week actigraphy […]
Related Product: MotionWatch
Publication Date: April 1, 2020
Quantifying Habitual Physical Activity and Sedentariness in Older Adults—Different Outcomes of Two Simultaneously Body-Worn Motion Sensor Approaches and a Self-Estimation
Applicable and accurate assessment methods are required for a clinically relevant quantification of habitual physical activity (PA) levels and sedentariness in older adults. The aim of this study is to compare habitual PA and sedentariness, as assessed with (1) a wrist-worn actigraph, (2) a hybrid motion sensor attached to the lower back, and (3) a […]
Related Product: MotionWatch
Publication Date: March 28, 2020
Daily energy balance and eating behaviour during a 14-day cold weather expedition in Greenland
We assessed energy compensation, appetite and reward value of foods during a 14-day military expedition in Greenland realized by 12 male French soldiers during which energy compensation was optimized by providing them with easy-to-eat palatable foods in excess. Although daily energy expenditure (estimated by accelerometry) stayed relatively constant throughout the expedition (15 ± 9 MJ.d-1), […]
Related Product: MotionWatch
Publication Date: March 18, 2020
Napping in high-performance athletes: sleepiness or sleepability?
Daytime napping is a common practice in high-performance athletes, and is widely assumed to reflect sleepiness arising from sports-related sleep debt. The possibility that athlete naps may also be indicative of ‘sleepability’, a capacity to nap on demand that is only weakly related to homeostatic sleep pressure, has not previously been tested. The present study […]
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Publication Date: March 16, 2020
Building a device-free system to prevent fractures in older people with musculoskeletal ambulatory disability symptom complex
This study aimed to measure the physical ability to cope with daily life and perceptions of older people at high risk of sarcopenia. We surveyed parameters to predict the risk of sarcopenia and factors worsening the condition. We used a pretest among five participants to check the relevance and validation of measures for (1) physical […]
Related Product: MotionWatch
Publication Date: March 15, 2020
Prospective association between suicide cognitions and emotional responses to a laboratory stressor: The mediating role of nightly subjective sleep quality
Background Sleep is a reliable correlate of suicidal thoughts and behaviors (STBs), yet few studies have directly examined negative affect in the context of this association. The present study combined daily experience methods with a laboratory paradigm to investigate suicide cognitions as a predictor of emotional responses to environmental stressors, and tested the role of […]
Related Product: MotionWatch
Publication Date: March 15, 2020
Sleep and intrusive memories immediately after a traumatic event in emergency department patients
Study objectives Intrusive memories of psychological trauma are a core clinical feature of posttraumatic stress disorder (PTSD), and in the early period post-trauma may be a potential target for early intervention. Disrupted sleep in the weeks post-trauma is associated with later PTSD. The impact of sleep and intrusive memories immediately post-trauma, and their relation to […]
Related Product: MotionWatch
Publication Date: March 5, 2020
Acupuncture for insomnia with short sleep duration: protocol for a randomised controlled trial
Introduction Insomnia with short sleep duration has a more serious negative impact on patient health. The existing literature suggests that medication therapy is more effective for this phenotype of insomnia compared with cognitive–behavioural therapy. However, the potential side effects of hypnotic medications hinder their clinical application. Acupuncture has been widely used in the treatment of […]
Related Product: MotionWatch
Publication Date: March 1, 2020
Primary care treatment of insomnia: study protocol for a pragmatic, multicentre, randomised controlled trial comparing nurse-delivered sleep restriction therapy to sleep hygiene (the HABIT trial)
Introduction Insomnia is a prevalent sleep disorder that negatively affects quality of life. Multicomponent cognitive-behavioural therapy (CBT) is the recommended treatment but access remains limited, particularly in primary care. Sleep restriction therapy (SRT) is one of the principal active components of CBT and could be delivered by generalist staff in primary care. The aim of […]
Related Product: MotionWatch
Publication Date: March 1, 2020
Chronobiological aspects of sleep restriction modulate subsequent spontaneous physical activity
Purpose First evidence suggests that chronobiological aspects of sleep restriction affect metabolic conditions. Our aim was to investigate whether spontaneous free-living physical activity likewise is affected by chronobiological timing of short sleep. Methods In an experimental randomized, balanced cross-over design, eleven healthy, normal-weight (BMI: 23.9 ± 0.4 kg/m2) men were evaluated. Physical activity was assessed […]
Related Product: MotionWatch
Publication Date: March 1, 2020
Correlates of disrupted sleep–wake variables in patients with advanced cancer
Objectives High rates of sleep difficulties have been found in patients with advanced cancer. However, not much is known about factors that are associated with sleep impairments in this population and that could constitute their potential risk factors or consequences. This study conducted in patients with cancer receiving palliative care aimed to evaluate the relationships […]
Related Product: MotionWatch
Publication Date: February 19, 2020
Sleep disruption after brain injury is associated with worse motor outcomes and slower functional recovery
Background and Aims: Sleep is important for consolidation of motor learning, but brain injury may affect sleep continuity and therefore rehabilitation outcomes. This study aims to assess the relationship between sleep quality and motor recovery in brain injury patients receiving inpatient rehabilitation. Methods: 59 patients with brain injury were recruited from two specialist inpatient rehabilitation […]
Related Product: MotionWatch
Publication Date: February 18, 2020
Scheduled afternoon–evening sleep leads to better night shift performance in older adults
Objectives This study investigated whether an intervention designed to reduce homeostatic sleep pressure would improve night shift performance and alertness in older adults. Methods Non-shift workers aged 57.9±4.6 (mean±SD) worked four day (07:00–15:00) and four night shifts (23:00–07:00). Two intervention groups were instructed to remain awake until ~13:00 after each night shift: the sleep timing group (ST; […]
Related Product: MotionWatch
Publication Date: February 13, 2020
Sleep-Wake Cycle in Alzheimer’s Disease Is Associated with Tau Pathology and Orexin Dysregulation
Background:Alzheimer’s disease (AD) is the most common form of dementia. It is mainly characterized by a progressive deterioration of cognition, but sleep-wake cycle disturbances frequently occur. Irregular sleep-wake cycle, insomnia, and daytime napping usually occur in patients with AD in the course of the disease. Objective:The aim of the present study was to verify the […]
Related Product: MotionWatch
Publication Date: February 10, 2020
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