Can these devices accurately detect sleep-wake patterns?
Discover the answer and how these data may be used to help you to sleep better.
What Is Actigraphy?
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Actigraphy is the continuous measurement of activity or movement with the use of a small gear called an actigraph.
Periods of movement suggest wakefulness while those of relative stillness would likely correspond to sleep or quiescence.
What Does an Actigraph Look Like?
An actigraph is a small, wristwatch-sized equipment.
It is lightweight and typically worn on a limb, such as at the wrist or ankle.
It may be incorporated into a watch.
It may also be a clip-on unit that can be applied to your clothing as an accessory.
More and more, these devices are becoming integrated into other everyday items such as clothing or bedding.
It uses something called an accelerometer to record motion.
These are often integrated into smartphones and can also be separate devices.
This information is then used to create a graph.
Actigraphs may be worn for weeks or even months.
Generally, medical actigraph devices can record data for 24 hours per day for about two weeks.
Common models can take measurements up to 32 times per second.
Devices that can incorporate additional measurements may eventually be able to detect the measures needed to truly identify sleep.
Frequent awakenings at night may suggest obstructive sleep apnea and steps may occur without consciousness in parasomnias like sleepwalking.
The memory may be limited, so it is necessary to download the information at regular intervals.
In addition, often the results must be correlated with asleep diary.
As noted, these devices currently cannot accurately detect sleep stages.
In some cases, it may be a good first step in learning about your sleep.
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