Chronic sleep disturbance was associated with anhedonic depression in a study of young women. This suggests that a reciprocal relationship between nightly sleep disturbance and daily experiences of depression may explain how chronic comorbid states of insomnia and distress develop.

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Chronic sleep disturbance was associated with anhedonic depression in a study of young women. This suggests that a reciprocal relationship between nightly sleep disturbance and daily experiences of depression may explain how chronic comorbid states of insomnia and distress develop.