Virtual reality paradigm to capture sensorimotor alterations in depression

Mood disorders remain therapeutically challenging, with many patients failing to achieve full remission despite existing treatments. Research in Major Depressive Disorder (MDD) has largely focused on higher cognitive processes such as rumination, cognitive biases, and executive dysfunction. However, depression is inherently a disorder of embodiment, with prominent sensorimotor alterations. Across sensory modalities, patients show reduced visual contrast sensitivity, impaired auditory processing of nonspeech stimuli, altered pain thresholds, and decreased heartbeat perception accuracy. Alongside the motor functions are also altered by psychomotor retardation—including slowed speech, delayed initiation, immobility, and reduced facial expressivity, which remains prominent feature of depression. Despite the small number of studies that examine sensory or motor changes in depression, conventional methods for testing sensorimotor functions have several drawbacks. A critical limitation for testing sensorimotor functions using conventional lab-based paradigms often lacks ecological validity, failing to capture the dynamic, interactive nature of real-world environments. Consequently, they provide limited insight into how sensorimotor disruptions manifest in everyday functioning. To address this limitation, we are using virtual reality paradigms to develop controlled and close to realistic experimental environments. In this study we have developed an immersive and interactive, multi-modal virtual environment that simulates everyday home-based tasks involving motor planning, action execution, visual attention, auditory localization, and social interaction. These tasks collectively provide data on motor velocity, pauses, errors, movement trajectories, gaze patterns, speech prosody, and affective expression throughout the narrative-based experimental scenario. Preliminary analysis from pilot study of five participant’s motion from controller-derived kinematic data revealed clear inter-individual differences in hand movement velocity across participants, thus supporting the feasibility of the virtual reality paradigm.