A Qualitative study on commercially available:

Sleep Monitoring Systems and Sleep Analysis Tools

 

Hasina Adil¹, A.A. Koser², Alok Gupta³

¹Medi-Caps University, AB Road Pigdamber Rau, Indore 453331 (M.P.) India.

²Medi-Caps University, AB Road Pigdamber Rau, Indore 453331 (M.P.) India.

³PS India Indore 452001, (M.P.) India.

 

ABSTRACT:

Background: A sound sleep is the key parameter for healthy life. The monitoring of such vital parameter is very complex as it is associated with electrical waves generated by brain. In this paper, study focuses on comparison of various sleep monitors available commercially based on technique used and complexities involved- in, to analyze the quality of sleep. Method: This qualitative study consolidates the information from 1913 to 2017, about sleep, its importance and sleep monitoring systems. The conventional sleep monitoring method Polysomnography (PSG) to the wearable devices reviewed comparatively. The study shows that sleep is a function of brain. Results: The data collected from various sources are compared and its result shows that 85% of commercially available system are not using the important parameter of brain signals, only 15% present commercial sleep monitoring system are based on Electroencephalograph. Conclusion: The study reveals that there is an actual need of sleep monitoring system. The available sleep monitors have a great scope for research to improve the quality of sleep analysis in daily life.

 

 

 

INTRODUCTION:

In the 19^th century, researcher had started the study about important biological function of human body that is sleep, to improvise the performance and efficiency of human brain. The sleep quality and quantity impact directly on human life style, occupation and health by improving one’s memory, maintaining blood pressure, keeping proper functioning of endocrine system and metabolism. Sleep loss and sleep disorders results in cardiovascular diseases, Obesity, Cancer, less productive at work place, restless, short temper, depressed and increased likelihood of accidents in the lives. To live quality of life it is necessary to understand sleep, its function, monitoring of sleep and sleep behavior of an individual. A daily sleep monitoring system is required for self-care.

 

 

Sleep is the fundamental physiologic activity of a body controlled by the central nervous system (CNS). It is a reversible behavioral state characterized by closed eyes, muscles relaxed, mobility decreased, minimal movement, low attention to the environment and lessened consciousness in which body becomes inactive but brain and other organs of body work in continuation for our physical, mental and emotional health. Sleep is necessary for physical health, for proper functioning of nervous system, neurocognitive function, energy conservation, neural plasticity and ecological adaptation. Sleep performance and its importance can be realized by the effects of its deprivation in which mood becomes imbalanced, learning becomes impaired and periods of temporary loss of consciousness, become clear^(1-3). In addition, researchers found correlations between sleeplessness and diseases like diabetes and cardiac⁽⁴⁾. A complete sleep is needed for smooth functioning of all biological processes to live quality of life. It gives support in healthy functioning of various organ systems in a body. Sleep conserves energy which cannot be attainable from quiet wakefulness⁽⁵⁾.

 

The researchers study the effect of sleep on the various organ system of human body to improve quality of life. The important role of sleep is in the functioning of the brain by improving memory and learning^(6–11), enhancement in attention, creativity and aid in making decisions. The ability to recall spoken language⁽¹²⁾, spatial memories^(13,14) auditory patterns⁽¹⁵⁾, motor skills^(16,17) and factual information^(18,19) has been raised by taking different types of sleep⁽²⁰⁾, and exceptions are found in the patterns of sleep^(21,22) from which the data is compelling. The ability of the brain to reorganized and reactivated its memories is enhanced by sleep⁽²³⁾. Lack of sleep leads to depression, suicide and risk-taking behavior.

 

During sleep, immune system of body release cytokines to kill bacteria, viruses and defend our body against illness⁽²⁴⁾. Sleep restores the immune system and its disturbance take part in the risk of infectious disease, cardiovascular disease, cancer, and major depression⁽²⁵⁾.

 

Feelings of hunger and fullness has been controlled and maintained by hormones named leptin and ghrelin which are chemically balanced by taking proper sleep. Furthermore, decreased glucose tolerance, increased risk of weight gain, hunger and appetite increases due to short sleep duration.^(26,27), and type 2 diabetes mellitus (T2DM) come into sight in the last decade^(28,29). Sleep is required to repair cell damage caused by metabolic processes, recovery and recuperative process of the body^(30,31,32).

 

Sleep plays vital role to heal and repair the blood vessels and heart. It maintains body blood sugar, blood pressure, and inflammation levels. Sleep loss-induced changes in cellular metabolic status can be reversed by taking balanced sleep⁽³³⁾. Short term sleep directly increases risk of cardiovascular disease^{(34,35,36, 37)}

 

Sleep produces testosterone, growth hormone, insulin hormone to build muscle mass and repair cells and tissues. Sleep debt results in normal ageing and age-related chronic disorders⁽³⁸⁾.

 

Irregular life style and demand of job like call centers impact directly on sleep hours of people. In long term, night shift workers found an increased risk for colon, prostate, breast and endometrial epithelial malignancies together with non-Hodgkin's lymphoma which contribute to all-cause mortality^{(39–42 ,43, 44, 45,46)}.

 

The performance of sportsperson depends on its physical and mental fitness⁽⁴⁷⁾, and is affected by the sleep awake time, temperature of body, and hormone regulation^(48). Currently, exercise performance due to sleep loss is limited^{(49,50,51,52,53–55)}.

 

A definite quantity and quality of sleep have reversed the impairments caused due to its deprivation⁽⁵⁶⁾. The quality of sleep is monitor by identifying the main stages of sleep and their time span as it changes due to brain activity and physiological functions of a body. In this manner, sleep occurrence can be detected. Normally human sleep is divided into Non Rapid Eye Movement (NREM) which is further subdivided into NREM1, NREM2, NREM3 and NREM4, and Rapid Eye Movement (REM) stages⁽⁵⁷⁾. Figure1 shows the different sleep stages with respect to time called hypnogram.

 

Fig. 1. Hypnogram.

 

The recorded patterns of sleep help in identification of different types of sleep disorders. The amount of time you spend in each stage also depends on your age. In this way one can check the status of sleep and its quality to improvise their medical and general wellness.

 

MATERIALS AND METHODS:

The present study was conducted from 1913 to 2017. In1913, Henri Pieron, a French psychologist, published a book called Le Probleme Physiologique Du Sommeil, the first physiological examination of sleep. His text is officially regarded as the start of modern sleep research. “The proposed mechanisms for the origin of sleep are varied and include the classical concept of central sleep regulation by thalamocortical relays⁽⁵⁸⁾, the brainstem⁽⁵⁹⁾, and the hypothalamus⁽⁶⁰⁾; local network regulation of sleep through sleep regulatory factors^(61–63); and decentral regulation involving cortical contributions^(59,64) and states of individual cortical neurons being either active or inactive⁽⁶⁵⁾”. In 1929 German psychiatrist Hans Berger first recorded human electrical brain waves and noted differences between activity patterns in the sleeping and waking brain. In 1936 Loomis explained different stages of sleep, based on electroencephalography (EEG). In 1950, Aserinsky and Klietman (1953) discovered REM sleep. It is related to dreaming in living organism. Finally, sleep has been split up into two types NREM and REM sleep. In 1957 Stanford University Psychiatrist William C. Dement, the “father of sleep medicine” teamed up with klietman, his former teacher, and created a sleep-stage classification system involving REM sleep and four stages of NREM sleep. Barring a few tweaks, the classification system remains in use today. Dement would also define sleep medicine as “the branch of medicine that deals with the sleeping brain and all manifestations and pathologies deriving there from.”⁽⁶⁶⁾. The sleep stages were standardized in 1968 by Rechtschaffen and Kales (R&K) based on EEG changes, dividing NREM sleep into a four further stages (stage I, stage II, stage III, stage IV)⁽⁵⁶⁾. It should be noted that some dreaming has been discovered during NREM sleep. Sleep and its stages are measured by using Polysomnography (PSG), Electroencephalography (EEG), Electro-oculogram (EOG), Electromyography (EMG), Pulse oximetry, Electrocardiogram (ECG) and Actigraphy.

 

In 1970 Dement established the Stanford Sleep Clinic, the country’s first full-scale sleep research center. This would pave the way for the creation of more than 1000 sleep clinics now in operation across the country. The commercial clinical PSG are developed and available in 1980. Multiple Sleep Latency Test (MSLT) introduced in the year 1982 as a diagnostic tool to determine sleep disorders having excessive daytime sleepiness. At the same time another test called maintenance of wakefulness test (MWT) is used to measure person alertness during day time. The recent development in electronics technology has change the complete medical electronic testing systems. In 1990 commercial sleep monitor Emfit QS is founded in market. Emfit is ballistocardiography based sleep tracker for the bed to monitor sleep. The Evalution of Microelectro Mechanical System (MEMS) Acceleration Transducer in year 2004 has introduced actigraphy based commercial sleep monitoring system in market.

 

In 2004, the American Academy of Sleep Medicine (AASM) standards commissioned the AASM Visual Scoring Task Force to review the R&K scoring system⁽⁵⁷⁾. Cardiac, arousals and respiratory events were also added to the scoring. This document resulted in the most significant being the combining of stages NREM 3 and NREM 4 into Stage NREM3⁽⁵⁷⁾. In 2005, the International Classification of Sleep Disorders (ICSD) classify eight types of sleep disorders in humans⁽⁵⁷⁾.

 

In 2007, the revised scoring was published as The AASM Manual for the Scoring of Sleep and Associated Events. It is found that NREM and REM sleep are alternating cycles. In 2008, a University of Wisconsin research team found that there is a high risk for life when person cannot take breathe during sleep. It is also considered as one of sleep disorder. Elsewhere, researchers used epidemiological data to link sleep deprivation with obesity and diabetes. The last decade has seen the emergence of sleep as a public health concern, with an increasing focus on the connection between poor sleep quality, chronic disease and socioeconomic factors^(66,67). Sleep monitoring could help people to understand need of quality sleep and its behavior while sleeping. There are two types of sleep monitors available for monitoring the sleep pattern Clinical sleep monitors and Commercial sleep monitors.

 

In clinical sleep monitors PSG, Multiple Sleep Latency Test (MSLT) and Clinical Actigraphy (2007) are widely used. These monitors are complex, required medical trained person and are expensive too for long-term (i.e., weeks, months) treatment for sleep monitoring⁽⁶⁸⁾. Especially for PSG, spending whole night in a hospital with dozens of wires hooked up is not comfortable idea for restful sleep⁽⁶⁹⁾. The daytime sleepiness is detected by MSLT test at early stage of treatment⁽⁷⁰⁾. In actigraphy a device called an actigraph, is worn on a wrist, ankle, or trunk to monitor movement, sleep wake patterns and circadian rhythm abnormalities⁽⁷¹⁾. It is widely used to detect sleep disorders in a person suffering from neurological diseases such as Parkinson’s disease, Alzheimer’s disease, cerebral infarction, seasonal affective disorder, restless leg syndrome, vascular dementia⁽⁷²⁾. The advantage of actigraphy over traditional PSG is that it is less complicated, dozens of wires are not used and can continuously record pattern of sleep for 24-hours or even longer⁽⁷³⁾. In the diagnosis of children, actigraphy is widely accepted⁽⁷⁴⁾.

 

In 2006, the advancement to technology, miniaturization and lack of availability of time leads to portable sleep monitoring devices. These commercially available monitors allow individuals to record and analyze their own sleep pattern in real-world environment that is home. Our study includes both non-wearable and wearable and sleep monitoring systems.

 

Table-1: Comparative study of technology of Commercially Available Sleep Monitors

 

 

 

 

 

The study of available commercial sleep monitors implicates that in near future smart sleep tracking device market is expected to grow at its highest level because of awareness and health concern pupil numbers are increasing in our society⁽⁷⁵⁾. Table-1 shows the classification of commercially available sleep monitors (2006-2017) based on techniques and sensors position.

 

RESULT:

The study shows that wearable device captures 65% of market share and 37.5% are non-wearable devices. The Pie Chart 1 (Figure2) implicates the study of above 40 type of popular Sleep monitors. This shows that 37.5% of sleep monitors are based on actigraphy technique, 22.5% are on Force sensor-based system, on the third rank Nightstand systems scores 17.5%, while sleep is a function of brain but EEG based system is on fourth rank with 15% contribution in commercial sleep monitoring market. The comparative study of these sleep monitors shows the demand for a new technically validated scheme of sleep monitoring system, at low cost so that person can monitor such a vital and complex parameter of life by its own at home.

 

Figure 2: Pie Chart-1 Sleep Monitor Market Share Based on Different Technologies.

 

DISCUSSION:

Our study related to sleep, its disorders and deprivation shows that 20% of world population is sleep deprived and percentage of Indians are 93%⁽⁷⁶⁾. People come in depression and think of suicide due to problems arise from disturbances of sleep and its disorders⁽⁵⁶⁾, and taking pills either for treatment or sleep well^(77-79). Secondly, sleep has significant impact on economy that is estimated about tens of billions of dollars annually, so its treatment is costly and available sleep monitors are also expensive. Furthermore, sleep is a function of brain but very few products are based on EEG technique^(80-82). Third, a wide range of various design sleep monitoring devices available in the market are based on ECG and actigraphy which are obtrusive to patients^(83-90) belongs to America, China, Japan, Korea etc and none of them belongs to India.

 

In conclusion, the paper delivers information about sleep and need of sleep monitoring system. There is wide range of sleep monitoring system with different technologies available in the market in the form of wearable and non-wearable devices. These devices are having large number of features to monitor individual health in all aspects. However, the information about their data processing technique is not disclosed as a trade secret and none of the device provides raw data to process it further. The validation of such devices is only on individual’s experience with it, no technical correlation data or information is provided. Very few products have such clinical analysis information. Daily quality of sleep monitoring is essential in today’s lifestyle to avoid futuristic health related issues. A clinically proven compact household device is required which gives close correlation to the medical test set up, to set bench mark for the further research.

 

REFERENCES:

1.      Banks S, Dinges DF. Behavioral and physiological consequences of sleep restriction. J Clin Sleep Med 2007; 3: 519-528.

2.      Van Dongen HP, Maislin G, Mullington JM. The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. Sleep 2003; 26: 117-126.

3.      Knutson KL, Spiegel K, Penev P. The metabolic consequences of sleep deprivation. Sleep Med Rev 2007; 11: 163-178.

4.      Fung Po Tso, David R. White, Simon J, Jeremy Singer, Dimitrios P. Pezaros. The Glasgow Raspberry Pi Cloud: A Scale Model for Cloud Computing Infrastructures. Distributed Computing Systems Workshops (ICDCSW). 2013 IEEE 33rd International Conference on. Philadelphia. 2013; 108-112.

5.      Berger RJ, Phillips NH. Energy conservation and sleep. Behav Brain Res 1995;69: 65-73.

6.      Ambrosini MV, Giuditta A. Learning and sleep: the sequential hypothesis. Sleep Med Rev 2001; 5(6): 477–490.

7.      Ribeiro S, Mello CV, Velho T. Induction of hippocampal long-term potentiation during waking leads to increased extrahippocampal zif-268 expression during ensuing rapid-eye-movement sleep. J Neuroscience 2002; 22: 10914-10923.

8.      Ribeiro S, Gervasoni D, Soares ES. Long- novelty-induced neuronal reverberation during slow-wave sleep in multiple forebrain areas. PLo SBiol 2004; 2: E24.

9.      Huber R, Ghilardi MF, Massimini M. Local sleep and learning. Nature 2004; 430: 78-81.

10.   Walker. MP, Stickgold R. Sleep-dependent learning lasting and memory consolidation. Neuron 2004; 44: 121-133.

11.   Stickgold R, Walker MP. Memory consolidation and reconsolidation: what is the role of sleep? Trends Neurosci 2005; 28: 408-415.

12.   Fenn KM, Nusbaum HC, Margoliash D. Consolidation during sleep of perceptual learning of spoken language. Nature 2003; 425: 614-616.

13.   Ferrara M, Iaria G, De Gennaro LThe role of sleep in the consolidation of route learning in humans: a behavioural study. Brain Res Bull 2006; 71: 4-9.

14.   Peigneux P, Laureys S, Fuchs S. Are spatial memories strengthened in the human hippocampus during slow wave sleep? Neuron 2004; 44: 535-545.

15.   Gottselig JM, Hofer-Tinguely G, Borbely AA. Sleep and rest facilitate auditory learning. Neuroscience 2004; 127: 557-561.

16.   Peters KR, Smith V, Smith CT. Changes in sleep architecture following motor learning depend on initial skill level. J Cogn Neurosci 2007;19: 817-829.

17.   Stickgold R. Neuroscience: a memory boost while you sleep. Nature 2006;444: 559-560.

18.   Ellenbogen JM, Payne JD, Stickgold R. The role of sleep in declarative memory consolidation: passive, permissive, active or none? Curr Opin Neurobiol 2006; 16: 716-722.

19.   Ellenbogen JM, Hulbert JC, Stickgold R. Interfering with theories of sleep and memory: sleep, declarative memory, and associative interference. Curr Biol 2006;16: 1290-1294.

20.   Roth TC, Rattenborg NC, Pravosudov VV. The ecological relevance of sleep: the trade-off between sleep, memory and energy conservation. Philos Trans R Soc Lond B BiolSci 2010; 365: 945-959.

21.   Fogel SMS, C. T. Declarative learning dependent changes in theta power during REM sleep. Sleep 2006; A375–A375.

22.   Huber R, Ghilardi MF, Massimini M. Local sleep and learning. Nature 2004;430: 78-81.

23.   Hennevin E, Huetz C, Edeline JM. Neural representations during sleep: from sensory processing to memory traces. Neurobiol Learn Mem 2007; 87: 416-440.

24.   Villafuerte. G, Miguel-Puga. A and Rodriguez E.M., Machado. S and Manjarrez. E. and Arias-Carrion O. Sleep deprivation and oxidative stress in animal models: a systematic review. Oxid Med Cell Longev 2015; 2015: 234952.

25.   Irwin M.R. Why sleep is important for health: a psychoneuroimmunology perspective. Annu Rev Psycho 2015; l66: 143-172.

26.   Chaput J.P, Despres J.P, Bouchard C. The association between sleep duration and weight gain in adults: a 6-year prospective study from the Quebec Family Study. 2008; 31:517-523.

27.   Patel SR, Malhotra A, White DP. Association between reduced sleep and weight gain in women. Am J Epidemiol 2006;164: 947-954.

28.   Cappuccio FP, D'Elia L, Strazzullo P. Quantity and quality of sleep and incidence of type 2 diabetes: a systematic review and meta-analysis. Diabetes Care 2010; 33: 414-420.

29.   Cooper AJ, Westgate K, Brage S. Sleep duration and cardiometabolic risk factors among individuals with type 2 diabetes. Sleep Med 2015; 16: 119-125.

30.   Mignot E. Why we sleep: the temporal organization of recovery. PLoSBio 2008; l6: e106.

31.   Adam K. Sleep as a restorative process and a theory to explain why. Prog Brain Res 1980; 53:289-305.

32.   Oswald I. Sleep as restorative process: human clues. Prog Brain Res 1980; 53: 279-288.

33.   Wisor J.P. A metabolic-transcriptional network links sleep and cellular energetics in the brain. Pflugers Arch 2012; 463: 15-22.

34.   Ayas NT, White DP, Manson JE. A prospective study of sleep duration and coronary heart disease in women. Arch Intern Med 2003; 163: 205-209.

35.   Hoevenaar-Blom M.P, Spijkerman A.M, Kromhout D. Sleep duration and sleep quality in relation to 12-year cardiovascular disease incidence: the MORGEN study. Sleep 2011; 34:1487-1492.

36.   Mallon L, Broman JE, Hetta J. Sleep complaints predict coronary artery disease mortality in males: a 12-year follow-up study of a middle-aged Swedish population. J Intern Med 2002; 251: 207-216.

37.   Wang Q, Xi B, Liu M. Short sleep duration is associated with hypertension risk among adults: a systematic review and meta-analysis. Hypertens Res 2012; 35: 1012-1018.

38.   Spiegel K, Leproult R, Van Cauter E. Impact of sleep debt on metabolic and endocrine function. Lancet 1999; 354: 1435-1439.

39.   Conlon M, Lightfoot N, Kreiger N. Rotating shift work and risk of prostate cancer. Epidemiology 2007;18: 182-183.

40.   Kubo T, Ozasa K, Mikami K. Prospective cohort study of the risk of prostate cancer among rotating-shift workers: findings from the Japan collaborative cohort study. Am J Epidemiol 2006;164: 549-555.

41.   Kubo T, Oyama I, Nakamura T. Retrospective cohort study of the risk of obesity among shift workers: findings from the Industry-based Shift Workers' Health study, Japan. Occup Environ Med 2011;68: 327-331.

42.   Parent M.E, El-Zein M, Rousseau M.C. Night work and the risk of cancer among men. Am J Epidemiol 2012; 176: 751-759.

43.   Vgontzas A.N, Fernandez-Mendoza J, Liao D. Insomnia with objective short sleep duration: the most biologically severe phenotype of the disorder. Sleep Med Rev 2013;17: 241-254.

44.   Mallon L, Broman J.E, Hetta J. Sleep complaints predict coronary artery disease mortality in males: a 12-year follow-up study of a middle-aged Swedish population. J Intern Med 2002; 251:207-216.

45.   Dew M.A, Hoch C.C, Buysse D.J. Healthy older adults' sleep predicts all-cause mortality at 4 to 19 years of follow-up. Psychosom Med 2003; 65: 63-73.

46.   Kripke D.F, Garfinkel L, Wingard D.L. Mortality associated with sleep duration and insomnia. Arch Gen Psychiatry 2002 ;59: 131-136.

47.   Bishop D. An applied research model for the sport sciences. Sports Med 2008;38: 253-263.

48.   Drust B, Waterhouse J, Atkinson G. Circadian rhythms in sports performance—an update. ChronobiolInt 2005; 22: 21-44.

49.   Fullagar H.H, Skorski S, Duffield R. Sleep and Athletic Performance: The Effects of Sleep Loss on Exercise Performance, and Physiological and Cognitive Responses to Exercise. Sports Med 2015;45(2):161-86.

50.   Banks S, Dinges D.F. Behavioral and physiological consequences of sleep restriction. J Clin Sleep Med 2007;3: 519-528.

51.   Samuels C. Sleep, recovery, and performance: the new frontier in high-performance athletics. Neurol Clin 2008;26: 169-180; ix-x.

52.   Durmer J.S, Dinges D.F .Neurocognitive consequences of sleep deprivation. Semin Neurol 2005;25: 117-129.

53.   Venter R.E . Perceptions of team athletes on the importance of recovery modalities. Eur J Sport Sci 2014; 14 (1): S69-76.

54.   Erlacher D, Ehrlenspiel F, Adegbesan OA. Sleep habits in German athletes before important competitions or games. J Sports Sci 2011;29: 859-866.

55.   Juliff L.E, Halson S.L, Peiffer J.J. Understanding sleep disturbance in athletes prior to important competitions. J Sci Med Sport 2015; 18: 13-18.

56.   Mander B. A., Reid K. J., Baron K. G., Tjoa T., Parrish T. B., Paller K. A., Zee P. C. EEG measures index neural and cognitive recovery from sleep deprivation. The Journal of neuroscience: the official journal of the Society for Neuroscience 2010; 30(7): 2686–2693.

57.   Rinsho N. American Academy of Sleep Medicine, The international classification of sleep disorders, Japanese J. clinical medicine 2015;73(6): 916-23.

58.   Mc Cormick DA, Bal T. Sleep and arousal: thalamocortical mechanisms. Annu Rev Neurosci 1997;20: 185-215.

59.   Pace-Schott E.F, Hobson J.A. The neurobiology of sleep: genetics, cellular physiology and subcortical networks. Nat Rev Neurosci 2002 ;3: 591-605.

60.   Villablanca J.R. Counterpointing the functional role of the forebrain and of the brainstem in the control of the sleep-waking system. J Sleep Res 2004;13: 179-208.

61.   Daniel A. Barone and Ana C. Krieger. The Function of Sleep, AIMS Neuroscience 2015; 2 ( 2): 71-90.

62.   Porkka-Heiskanen T, Methylxanthines and sleep. Fredholm BB (ed) Methylxanthines, Handbook of experimental pharmacology 2011; 200: 331–348.

63.   Krueger J.M, Rector D.M, Roy S. Sleep as a fundamental property of neuronal assemblies. Nat Rev Neurosci 2008;9: 910-919.

64.   Pace-Schott E.F, Hobson J.A. The neurobiology of sleep: genetics, cellular physiology and subcortical networks. Nat Rev Neurosci 2002;3: 591-605.

65.   Vyazovskiy V.V, Olcese U, Hanlon E.C. Local sleep in awake rats. Nature 2011; 472:443-447.

66.   John WS, Daniel JB, Andrew LC, William CD, Rochelle G, Christian G, Cameron DH, Conrad I, Emmanuel M, Merrill MM, Kent EM, Barbara AP, Stuart FQ, Richard SR, Thomas R, Helmut SS, Michael HS, James KW, David PW. History of the development of sleep medicine in the United States. Journal of clinical sleep medicine: JCSM : official publication of the American Academy of Sleep Medicine 2005; 1(1): 61–82.

67.   Roebuck A, Monasterio V, Gederi E, Osipov M, Behar J, Malhotra A, Clifford GD, A review of signals used in sleep analysis. Physiological measurement 2013; 35(1): R1–R57.

68.   Chen Z., Lin M, Chen F., Lane N. D, Cardone G, Wang R, Li T, Chen Y., Choudhury T. and Campbell A.T. Unobtrusive sleep monitoring using smartphones. 7th International Conference on Pervasive Computing Technologies for Healthcare and Workshops, Venice 2013; 145-152.

69.   Henriksen, André and Haugen Mikalsen, Martin and Woldaregay, Ashenafi and Muzny, Miroslav and Hartvigsen, Gunnar and Hopstock, Laila and Grimsgaard, Sameline. Using Fitness Trackers and Smartwatches to Measure Physical Activity in Research: Analysis of Consumer Wrist-Worn Wearables, Journal of Medical Internet Research 2018; 20(3): e110.

70.   Roehrs T, Roth T., Multiple Sleep Latency Test: technical aspects and normal values. J Clin Neurophysiol. 1992;9(1):63-7.

71.   Timothy Morgenthaler, Cathy Alessi MD, Leah Friedman MD. Practice Parameters for the Use of Actigraphy in the Assessment of Sleep and Sleep Disorders: An Update for 2007. Sleep 2007; 30( 4): 519–529.

72.   Jennifer L. Martin, and al. McCarthy M, Muehlhausen. Wrist Actigraphy: Actigraphy devices a real impact on clinical research - Kayentis.htm Chest. 2011; 139(6): 1514–1527.

73.   Ancoli-Israel S, Cole R, Alessi C. The role of actigraphy in the study of sleep and circadian rhythms. American Academy of Sleep Medicine Review Paper. SLEEP 2003;26(3):342-92.

74.   Corkum P., Tannock R., Moldofsky H., Hogg-Johnson S. and Humphries T. Actigraphy and parental ratings of sleep in children with Attention-Deficit/Hyperactivity Disorder (ADHD). Sleep 2001; 24( 3): 303–312.

75.   Smart Sleep Tracking Device Market :Global Demand Analysis & Opportunity Outlook 2024 Published On : 11:40 PM, 3rd October, 2017 REP-ID-373 Category: ICT & Electronics.

76.   Siddalingaiah HS, Chandrakala D, Singh A. Sleep pattern, sleep problems and comorbidities among resident doctors at a tertiary care institution in India: a cross sectional study. Int. J. Community Med Public Health 2017; 4(12): 4477-4484.

77.   Stranges S, Tigbe W, Gómez-Olivé FX, Thorogood M, Kandala NB. Sleep problems: an emerging global epidemic? Findings from the INDEPTH WHO-SAGE study among more than 40,000 older adults from 8 countries across Africa and Asia. SLEEP 2012; 35(8): 1173–1181.

78.   Mullington JM, Haack M, Toth M. Cardiovascular, inflammatory, and metabolic consequences of sleep deprivation. Prog Cardiovasc Dis 2009 ;51: 294-302.

79.   Irwin MR .Why sleep is important for health: a psycho neuro immunology perspective. Annu Rev Psychol 2015;66: 143-172.

80.   Hennevin E, Huetz C, Edeline JM. Neural representations during sleep: from sensory processing to memory traces. Neurobiol Learn Mem 2007; 87: 416-440.

81.   Colten, H. R., & Altevogt, B. M. (Eds.). Sleep disorders and sleep deprivation: An unmet public health problem. Washington, DC, US: National Academies Press 2006.

82.   Velicu O. R., Madrid N. M.,. Seepold R, Velicu O. R., Madrid N. M. and Seepold R. Experimental sleep phases monitoring. IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI), Las Vegas, NV, 2016;625-628.

83.   Suzuki T., Ouchi K., Kameyama K. and Takahashi M. Development of a sleep monitoring system with wearable vital sensor for home use. In Proceedings of the International Conference on Biomedical Electronics and Devices 2009; 326-331.

84.   Przystup P., Bujnowski A., Rumiński J. and Jerzy Wtorek. A Detector of Sleep Disorders for Using at Home, Journal of Telecommunication and Technology 2014; 2: 70-78.

85.   Chandana V.K, Narang S, Bansal Y.Sleep Disorder Recognition using Wearable Sensor and Raspberry Pi. International Journal of Computer Science and Information Technologies 2015; 6 (4):3938-3942

86.   Velicu O. R, Madrid N. M. and Seepold R., Experimental sleep phases monitoring, 2016 IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI), Las Vegas, NV, 2016; 625-628.

87.   Krystal A.D., Edinger, J.D. Measuring sleep quality. Sleep Medicine 2008;9 (1), S10-7.

88.   Kryger M.H., Roth T., Carskadon, M.A. & Dement, W.C., Monitoring and staging human sleep, Principles and practice of sleep medicine 2011; 5: 16-26.

89.   Brown R.E, Basheer R, McKenna J.T. Control of sleep and wakefulness. Physiol Rev 2012; 92: 1087-1187.

90.   Wolpert AE, A Manual of Standardized Terminology and Scoring System for Sleep Stages of Human Subjects. Archives of General Psychiatry1963; 20: 246.

 

 

 

 

 

Received on 19.03.2020           Modified on 11.04.2020

Accepted on 13.05.2020         © RJPT All right reserved