Understanding Activity Limitations in Depression: Integrating the Concepts of Motivation and Volition From Health Psychology Into Clinical Psychology

Behavioral activation plays an important role in the treatment of depression. Although the development of activation treatments has made important progress in the past decades, effects are still low to moderate. This paper illustrates how the understanding and treatment of activity limitations in depression can be improved through the integration of theories from health psychology. One of the leading theories is the health action process approach (HAPA; Schwarzer, Lippke, & Luszczynska, 2011). In accordance with the HAPA, we argue that reasons for activity limitations can be divided into problems of intention formation (motivational problems) and problems of intention implementation (volitional problems). To date, depression research has primarily focused on motivational deficits. With regard to the HAPA, we discuss different aspects of motivational deficits by reviewing common constructs such as negative thoughts, learned helplessness, loss of reinforcers, or self-efficacy. In addition, we demonstrate that volitional deficits are also important for explaining activity limitations and should be taken into account more. Volitional deficits in depression are documented by behavior studies focusing on self-regulation and procrastination; additionally, evidence of volitional deficits has been found in research on executive functions and in neurobiology. In conclusion, the HAPA contributes to a better understanding of activity limitations in depression: The reviewed literature demonstrates that depression is associated with motivational and volitional deficits. Each of these two kinds of deficits should be treated with a different intervention technique (e.g., values assessment vs. activity scheduling). Beyond this relevance for clinical psychology, implications for health psychology are discussed.