Why are some people heavier sleepers than others?

Why are some people heavier sleepers than others? A report from a recent issue of current biology finds sounder sleepers show a certain pattern of spontaneous brain rhythms that light sleepers do not.

During sleep, brain waves become slow and organized, except for brief bursts of faster-frequency waves called sleep spindles. Those bursts of activity -- more prevalent among deep sleepers -- are produced by a portion of the brain called the thalamus, which regulates all our senses, except smell.

According to researchers from Harvard medical school, these sleep spindles block certain sounds. So the more spindles a person's brain generates, the more stable their sleep.

Researchers say they hope to come up with ways to enhance sleep spindles either through behavioral techniques, drugs, or devices, but at this point, they're not sure exactly why spindles are more predominant in certain people, so more research is needed.