If you have been convinced that the cool side of the pillow actually helps you to sleep better, you may not be too far off the mark, according to recent research presented at the Associated Professional Sleep Societies meeting.
In a study of 12 people suffering from insomnia and 12 healthy controls, researchers found that cooling the head helped the insomniacs sleep longer and fall asleep faster. This was accomplished by using a specially designed cooling cap that circulated water at cool temperatures.
This study was based on earlier research that suggests that restless sleepers have higher than normal brain activity in the frontal cortex while trying to sleep. The caps allow the brain's temperature to be reduced, which may in turn promote normal sleep.
One might also imagine that turning over your pillow may help to accomplish the same thing.