ABSTRACT
The aim of this chapter is to examine one central aspect of daily functioning that is not comprehensively incorporated into psychological formulation – that of sleep. The rationale behind incorporating sleep as a key variable in formulation will be explored through its function, its impact on various psychological processes and how it relates to mental health. The chapter offers a thorough review of the literature that explores whether sleep difficulties are a causal factor for various psychological disorders, or whether they are, in fact, symptoms associated with these disorders. The fundamental characteristics of sleep including stages, optimal duration and regularity are discussed. The influence of sleep on emotion will be examined and its importance in formulating and understanding of distress will be highlighted. The complex relationship between sleep and cognitive and emotional health will be explored under headings such as memory, learning, insight, inhibition, decision making and emotional processing. This chapter also navigates the reader through some practical ways in which they might examine their client's sleeping patterns in clinical assessment, both informally by incorporating pertinent open-ended questions into therapeutic dialogue and formally, by using psychometric measures. Having an understanding of quality of sleep and how it impacts on a person's well-being has clear implications for improving how mental health practitioners formulate psychological distress.
