Psychophysiological relaxation through robot-guided mindfulness for persons with (visual and) intellectual disabilities

Individuals with intellectual disabilities (ID), with or without visual impairments (VI), are at heightened risk of stress, yet often struggle to independently perform mindfulness-based exercises shown to alleviate stress and promote relaxation. Social robots may offer effective guidance, but it remains essential to understand which robot features contribute to this effectiveness. This preregistered randomized controlled trial (N = 75 adults with ID/VI) examined whether robot-guided mindfulness using a humanized robot voice enhances relaxation compared to a standard robot voice. In addition, we compared robot guidance to an audio recording of a human therapist and to in-person therapist guidance. During two sessions, participants completed three mindfulness exercises (breathing, visualization, and tension release) after a mild stressor. Autonomic (electrodermal and cardiac activity), behavioral (attention, participation, emotion), and self-reported stress (arousal, valence) were measured. No significant autonomic differences emerged between humanized and standard robot voices. The therapist condition showed higher electrodermal arousal than the robot conditions, while the audio recording resulted in the slowest heart rate. Behaviorally, both the therapist and the robot with the humanized voice elicited higher participation and more positive emotion than the audio recording. Although voice characteristics did not influence physiological relaxation, embodied guidance (robot or therapist) supported behavioral engagement more effectively than audio-only delivery.