A reader asks:

 My daughter has been diagnosed with SAD and has purchased a light box which is helping her with waking and sleeping. She is 22 years old. Since she was about 10 years old, she has slept in the basement in a room without any windows. She has always had great difficulty waking up in the morning and going to sleep at night. Could sleeping in a room without natural light have had an impact on her sleep cycle?


Amen and amen. Our bodies have a physiological NEED to receive natural (or appropriate artificial) light early in the morning in order to stay in sync with external day and night. Dark basement conditions provide an environment conducive to developing and maintaining delayed sleep phase syndrome (DSPS). This can often be corrected with light therapy.