Background: Traumatic brain injury (TBI) is a leading cause of death and disability among young adults. The impairment of the often very young patients in daily life is a heavy burden for the affected person and leads to high healthcare costs. In recent years, electrostimulation of neurons has been suggested a promising approach to induce functional recovery of injured neuronal connections. However, standard electrode stimulation techniques require invasive methods and wiring of the patient. Purpose: We aim to combat TBI-induced disabilities by re-establishing neuronal connectivity. We will use light-sensitive semiconductors (photocaps) made from industrial colorants. They are easily available, stable, and non-toxic. Photocaps enable electrical stimulation of neurons with safe light intensities without the need for external wiring. Hypothesis: We suppose that the stimulation of neuronal cells via light-activated photocaps fosters functional recovery after TBI. Approach: In a multidisciplinary research approach we investigate the photocaps’ performance and effects on living systems. Cultured cells are an invaluable tool to develop optimal stimulation parameters before progressing to healthy and injured brain tissue. We will investigate the optimal time window after TBI in which stimulation yields the most extensive regenerative results. Our interdisciplinary research program brings together young independent researchers with backgrounds from neuroscience (Dr. Muammer Ücal), structural biology (Dr. Karin Kornmüller), electrophysiology (Dr. Susanne Scherübel) and electrical engineering (Dr. Theresa Rienmüller). Experiments will be conducted at the Medical University of Graz and Graz University of Technology.