Sleep induction

Sleep induction is the deliberate effort to bring on sleep by various techniques or medicinal means, is practiced to lengthen periods of sleep, increase the effectiveness of sleep, and to reduce or prevent insomnia.

Dim or dark surroundings with a peaceful, quiet sound level are conducive to sleep. Retiring to a bedroom, drawing the curtains to block out daylight and closing the door are common methods of achieving this. When this is not possible, such as on an airplane, other methods may be used, such as masks and earplugs for sleeping which airlines commonly issue to passengers for this purpose.

To relax and encourage sleep, a meditation in the form of guided imagery may be used. The stereotypical method is by counting sheep, imagining sheep jumping over a fence, while counting them.

In most depictions of the activity, the person envisions an endless series of identical white sheep jumping over a fence, while counting the number that do so. The idea, presumably, is to induce boredom while occupying the mind with something simple, repetitive, and rhythmic, all of which are known to help humans sleep. It may also simulate REM sleep, tiring people's eyes.

According to a BBC experiment conducted by researchers at Oxford University, counting sheep is actually an inferior means of inducing sleep.

The daily sleep/wake cycle is linked to the daily body temperature cycle. For this reason, a hot bath which raises the core body temperature has been found to improve the duration and quality of sleep. A 30-minute soak in a bath of 40 degrees Celsius (104 °F) – which raises the core body temperature by one degree – is suitable for this purpose.

Sex, and specifically orgasm, may have an effect on the ability to fall asleep for some people. The period after orgasm (known as a refractory period) is often a time of increased relaxation, attributed to the release of the neurohormones and prolactin.

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Wikipedia