Speaker : Leah Marie Roldan
Advisor: Prof. Tyler
Title: Tactile percept formation and integration for object feature encoding with electrical stimulation
Abstract: Touch is a sense that is often taken for granted, but it is critical to use and manipulate objects, feel ownership of one’s body, and make meaningful connections with others. Composite flat interface nerve electrodes (cFINEs) have been used to successfully restore touch to upper extremity amputees, changing how they grab objects and interact with those around them. Prior work using cFINEs revealed the relationship between stimulation paradigms and sensation at a single point of perception, such as the index fingertip, at a time. However, touch requires integrating multiple sensations across the finger and hand for tasks such as object recognition (stereognosis) and improved manual dexterity. For this study, an interleaved stimulation pattern was used between contact pairs to elicit multiple percepts on the hand. Stimulation pulse amplitude and frequency for these contact pairs were varied. The main hypothesis is that multi-contact stimulation with little to no axon population overlap will result in non-linear addition of tactile dimensions of sensation. For example, the overall percept area during interleaved stimulation will be significantly different from the sum of the areas resulting from single contact stimulation. Preliminary results have revealed trends in location, quality, and intensity integration during multi-contact stimulation that depend on percept size, location, orientation, and intensity during single percept stimulation. Understanding these integration patterns is vital for understanding how multi-percept stimulation could inform object feature extraction.