Motivation deficits in schizophrenia, major depressive disorder, and bipolar disorder impair functional outcomes, including work performance, educational engagement, and interpersonal relationships. These deficits also affect routine daily activities, which individuals often perceive as disproportionately effortful.

A recent preregistered meta-analysis examined the cognitive mechanisms underlying these impairments and their relevance to psychotherapies. Matthias Pillny, PhD, research associate at Universität Hamburg, Hamburg, Germany, and colleagues reported the findings in Psychological Bulletin.

Researchers conducted a systematic search of PubMed, APA PsycInfo, Embase, and Web of Science and included 68 studies with 3697 participants. Patients with depression, bipolar disorder, schizophrenia spectrum disorder, or an increased likelihood of developing any of these conditions were included.

Decision Mechanisms

In healthy individuals, decision-making involves weighing the effort required to achieve a specific goal against the probability of achieving that goal. “The higher the perceived benefit and probability, the greater the effort invested in reaching the goal. The automatic cognitive process is called effort-based decision-making (EBDM).” Pillny said in a press release from Universität Hamburg.

Measurable Deficits

The meta-analysis identified moderate impairments in EBDM among individuals with

• Schizophrenia spectrum disorders (g, -0.40) and bipolar disorder (g, -0.39).
• A lower impairment was observed in major depressive disorders (g, -0.28)
• No significant impairment was observed in the at-risk groups (g, -0.01).

The moderating factors included the number of probability conditions, ethnicity, sex, and severity of positive and negative symptoms.

Computational modeling has indicated that impaired EBDM may reflect increased sensitivity to effort, reduced responsiveness to rewards, and cognitive dysfunction in patients. Schizophrenia spectrum disorders are associated with inconsistent effort allocation and cognitive deficits, whereas depression and bipolar disorder are linked to increased effort sensitivity.

Therapeutic Implications

Individuals with depression and bipolar disorder may overestimate the effort required to achieve their goals and underestimate the potential benefits. “These individuals often cannot anticipate positive outcomes and perceive the required effort as insurmountable,” said Pillny.

These findings have practical implications for healthcare. Encouraging statements such as “Come on, it will be fun” are unlikely to improve motivation and may increase perceived pressure. Interventions focusing on anticipatory pleasure, such as visualization, may offer a more meaningful and effective approach.

This story was translated from Medscape’s German edition.