Sleep phase alarm clock
A sleep phase alarm clock is a special alarm clock that wakes a sleeping person taking into account their current sleep phase .
purpose
Different sleep phases go through during sleep :
- Light sleep phases 1 and 2
- Deep sleep phases 3 and 4 for physical relaxation
- Rapid eye movement phases (REM for short)
Between these phases and especially immediately before and after the REM phases, there are several so-called "almost awake moments" , i.e. H. Periods of shallow sleep, for example to change the lying position or to pull up the duvet.
A normal alarm clock is based exclusively on the time and ignores the sleep phase of the person to be awakened, with the risk that he will be awakened from a deep sleep phase and feel tired.
With sleep phase alarm clocks, you usually do not enter a fixed alarm time, but a time period. If the sleep phase alarm clock notices that you are almost awake during this period, the alarm will sound. This should make it much easier to wake up and get up, since you have almost woken up anyway. If the sleep phase alarm clock does not notice such a moment, the alarm will sound at the end of the set period.
functionality
A basic distinction is made between two different types of sleep phase alarm clocks - those that measure brain activity and those that measure physical movements.
To measure brain activity , special sensors are attached to the head, or more precisely to the forehead of the sleeper, with the help of which, similar to a sleep laboratory , sleep and its phases are analyzed and evaluated. The advantages of such products are the detailed analysis and thus the reliable determination of the ideal wake-up time. Disadvantages due to the complexity are the higher price and the sensors, which can be perceived as unpleasant.
For the measurement of motion movement knives, for example in the form of a bracelet, are used. Such products are based on the fact that you do not move during a deep sleep phase, but you do in the (almost) waking moments. In addition to the lower price, the advantage is that they are usually more comfortable to wear. Such sleep phase alarm clocks are somewhat less precise, but still avoid waking up during the deep sleep phase.
Programs for use on a smartphone with a motion sensor are an inexpensive option . However, individual tests revealed insufficient accuracy in recognizing the respective sleep phase.
Alarm clocks that are intended to set the wake-up time without the use of body sensors through a longer-term analysis of the confirmation of wake-up impulses by the user are also available.
Scientific evidence
So far, only a few (isolated) sleep phase alarm clocks have been able to provide scientific proof of an improvement in the morning mood. Sustainable, reliable evidence is only used when the results are statistically significant, i.e. H. if clear improvements were found in (some of the) test persons which, with a probability of at least 95%, are not due to chance.
Web links
- Mortimer yaw mills; Well rested in everyday study life (sleep phase alarm clock - test report); Via medici - online; June 16, 2007; viewed October 11, 2009