Wearable Technology for Sleep Applications
Sleep is a natural physiological process which has a profound effect upon our daily functioning and both our physical and mental health. The duration, regularity and quality of sleep varies with age and with a range of medical or psychological conditions. Interest in monitoring of sleep and circadian rhythms has grown exponentially in both research and clinical environments in recent years.
Monitoring of Sleep
Monitoring of sleep is typically performed by a sleep specialist within a controlled sleep lab environment. Typically the patient will have their sleep recorded by polysomnography whereby multiple electrodes are connected to the scalp along with sensors close to the eyes and a breathing rate sensor. The data are then scored by a specially trained sleep technician who can determine sleep stages and arousals during the sleep period.
While polysomnography is the gold standard for the measurement of sleep, there are some limitations. The patient may find the sensors and electrodes intrusive and will hence not sleep normally. Furthermore, patients rarely sleep well in strange surroundings (the so called ‘first night effect’) hence the sleep recorded in the lab may not be indicative of true sleep quality. Additionally, the sleep lab is a controlled environment where the timing of the sleep is controlled and the patient is isolated from external influences such as noise or natural light. Finally, the cost of running a full overnight PSG can be prohibitive.
Actigraphy provides an alternative to polysomnography outside of a laboratory setting where sleep staging is not required. Typically Actigraphy is performed by means of a wrist worn device similar to a wrist watch which continuously measures the physical movement of the patient. Software is used to determine periods of activity and rest to build a picture of sleep quality over days, weeks or months. The key advantage is that the patient is monitored in their normal environment and the measurement is unobtrusive. Actigraphy is particularly useful for circadian rhythm studies where the timing of the main sleep period can be clearly seen and software tools such as NPCRA provide means of analysing circadian stability. Additional light sensors provide a valuable additional data channel for examining light exposure/timing for chronobiological studies.
Actigraphy devices are normally worn continually and hence provide an insight into daytime physical activity and the behaviour of the subject during their normal daily routine.
Additionally, Actigraphy devices can be worn on the feet of patients suspected of suffering from PLMS and the data can provide valuable pre-screening prior to a more comprehensive lab-based test.
The MotionWatch is a small, light-weight, unobtrusive Actigraphy watch designed specifically for sleep and circadian rhythm research. The waterproof watch may be worn 24/7 to provide a detailed insight into subject behaviour in thier normal daily routine. With recording of up to 90 days, event marker button and light sensor, the MotionWatch 8 is the ideal tool for long-term subject monitoring.
Light-weight and waterproof
Fast direct USB transfer
No reader required
Ambient Light Sensor
Event marker button
User replaceable battery
Records for up to three months
Software includes NPCRA
Raw data export options
Optional PLMS Analysis software
Legacy .AWD compatible
The CamNtech PRO-Diary provides both subjective (questionnaire) and objective (accelerometer) data to gain a greater insight into patient behaviour. The PRO-Diary combines the all advantages of Actigraphy from the MotionWatch with fully flexible questionnaires in a single wrist-worn device. The PRO-Diary is a key tool in Ecological Momentary Assement studies where it is critical to capture subjective data ‘in the moment’.
Subjective and Objective data
Sleep and Activity Data
Ecological Momentary Assessment
High compliance vs paper diary
Up to 4 weeks battery life
Multiple question types
Scheduled or on demand alerts
Open data format
Touch sensitive controls
Clear, bright OLED display