Objective speech measures capture depressive symptoms and associated cognitive difficulties

Psychiatry lacks objective biomarkers for assessing depression, relying instead on subjective measures, such as the Hamilton Depression Rating Scale (HAMD-17). This study examined whether speech features could serve as objective markers of depressive symptoms and its associated cognitive difficulties. Sixty-six individuals with major depressive disorder (MDD) and 54 non-depressed control participants completed a speech assessment, responding to the prompt: "Please tell me how you are feeling today." Linguistic (valence, emotional intensity, agency) and acoustic (pitch, pitch variance, speech rate, time spent pausing) features were derived from natural language processing. These speech features were analyzed individually and collectively as a composite score representing overall speech disturbance. A subset of participants (40 with MDD, 38 controls) also completed a validated executive function task. ANCOVA models compared speech features between groups. Linear regression models examined associations between speech features, depression severity (HAMD-17), and performance on an executive function task. Compared to controls, individuals with MDD used language that was more negatively valenced, emotionally intense, and less agentic. They also demonstrated lower pitch, slower speech rate, and more time spent pausing. The composite speech score also differed between groups. Speech features and executive function were not associated with depression severity, as measured by the HAMD-17. However, several speech features were associated with executive function. Taken together, these findings suggest that speech features may provide a scalable, objective method for detecting depressive symptoms and associated executive difficulties.