Designing Touch: Intracortical Neurohaptic Feedback in Virtual Reality

Touch sensation offers complex and innate biological feedback that underlies dexterous interactions with our environments, making the restoration of touch an important component of functional brain computer interface (BCI). To advance synthetic touch research, I developed a virtual reality (VR) platform for use with human patients receiving intracranial neural implants for epilepsy evaluation (Fig. 1) [Paschall et al. (An immersive virtual reality platform integrating human ECOG & sEEG: implementation & noise analysis, 2022]. Following validation, noise, and user studies with this VR research platform, I designed a BCI experiment in which tactile information about contact with a virtual object was delivered to the brain through direct cortical stimulation (DCS). I recoined the term neurohaptics to describe this use of DCS for haptic feedback [Paschall et al. (2022 IEEE International Conference on Systems, Man, and Cybernetics (SMC). IEEE, 2022)]. I also developed a new way to deliver neurohaptic feedback using amplitude modulated DCS to evoke distinct and discriminable sensory percepts that better mimicked natural touch sensation [Paschall et al. (2022 IEEE International Conference on Systems, Man, and Cybernetics (SMC). IEEE, 2022)]. This work demonstrates the intrinsic interpretability of dynamic temporal structure in DCS and its utility in the restoration of touch sensation. It paves the way for further first-person VR-BCI neurohaptic design and brings a novel bidirectional BCI and cognitive neuroscience platform into the clinic for work with implanted neural devices in patient populations.