Cognitive Behavioral Therapy for Insomnia (CBTI): Sleep Restriction

This procedure, developed by Arthur Spielman, is designed to eliminate prolonged middle of the night awakenings. It doesn't aim to restrict actual sleep time but rather to initially restrict the time spent in bed. Subsequent steps consist of gradually increasing the time spent in bed. The initial time in bed is usually the average nightly total sleep time over the last week. However, the time allowed in bed should not be less than 5.5 hours, even for people who sleep less than 5.5 hours per night.

For example, consider a person who goes to bed at 11:00 p.m. and gets out of bed at 8:00 a.m. but sleeps on average only 6 hours per night. During the first step of this procedure this person will be in bed only 6 hours (e.g., 12:00 a.m. to 6:00 a.m.). This sounds harsh but after a week or so there will be a marked decrease in time spent awake in the middle of the night.

Usually people experience marked improvement in the quality of sleep after a week of restricted time in bed, but they also realize that that they are not getting enough sleep. In this case, the next step is to gradually extend the time spent in bed by 15 to 30 minutes, as long as wakefulness in the middle of the night remains minimal.

Each new extension of the time in bed is followed for at least a week before progressing to the next extension. The decision as to when to extend the time in bed is based on the percent of the time slept relative to the time spent in bed. This is called sleep efficiency. If the average sleep efficiency is 85% or more, then the time in bed is extended. If it is below 80% then the time is bed is further restricted. Otherwise the time in bed remains unchanged. There are several variants of this procedure, and the therapist chooses the one that best fits an individual patient. In all variants, the procedure continues until one reaches a point after which no further extension is necessary because the amount of sleep obtained is sufficient for optimal daytime function.