Sleep and psychiatric disorders: future directions.

Understanding of the relationship between co-occurring sleep and psychiatric disorders has undergone a radical change. The longstanding perspective that sleep problems invariably are a symptom of a psychiatric disorder is giving way to understanding that complex bidirectional relationships may exist. This change has opened doors to new directions in research and led to changes in guidelines for clinical practice. This article discusses promising future directions for building on this foundation, including developing lines of research currently underway, studying mechanisms that underlie the relationships between sleep and psychiatric disorders; and developing treatment strategies that target these mechanisms to lead to better treatment of sleep disorders and psychiatric disorders.