Incentive Sensitivity as a Behavioral Marker of Clinical Remission From Major Depressive Episode

Reduction of goal-directed behaviors is frequently observed in depression and may be linked to dysfunction of incentive motivation process.

To investigate whether incentive sensitivity could constitute a behavioral marker of clinical remission in major depression.

A handgrip force measurement device was employed to assess the impact of incentive motivation and emotional manipulation on the effort produced by remitted patients (n = 20) compared to matched depressed patients (n = 22) and healthy controls (n = 26). Depressed and remitted patients fulfilled the major depressive disorder DSM-IV criteria for current episode and remission state, respectively. The study was performed between March and July 2013.

Relative to patients with acute depression, patients after remission retrieved a normal sensitivity to incentives (t1,40 = 4.18, P < 1.5 × 10-4), but relative to healthy controls, they kept an abnormally high susceptibility to emotional arousal (t1,44 = 2.4, P = .02). Normalization of incentive sensitivity exhibited in the behavioral test was associated with improvement of apathy measured on the clinical scale.

Using a simple behavioral paradigm at patients' bedside, we could identify the factors influencing effort production, so as to discriminate remitted patients from both depressed patients and healthy controls.