Sleep patterns change with age, anxiety levels, and many other factors. Normally, younger people have more concentrated periods of deep sleep, while older people have more periods of REM sleep.
Reviewed last on: 6/12/2009
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.