In addition to developing wearable sensors to measure and study human motion, we also study how the brain interprets information coming from biological sensors to perceive motion. We use unique experimental protocols to probe the brain's perception to different types of motion, and use these to drive the development of novel stochastic models to simulate how we think the brain's neural circuitry makes sense of sensory information. In the future, we will use these same approaches to also study how sensory information are utilized in feedback motor control for standing balance and locomotion tasks, and how our stochastic models might act as a framework for describing motor learning.
We are actively looking for students with a strong background in modeling dynamical systems, both with traditional methods (state space, linear time invariant control), and stochastic methods (Markov Decision Processes, Bayesian estimation).
The vestibular sense is often considered the human sixth sense. Located in the inner ear, the semicircular canals and otoliths that make up the vestibular organ are sensitive to both angular and linear accelerations respectively. Because they are sensitive to accelerations, the brain must integrate these to form perceptions of velocity and position. Thus, there is a clear central mechanism underlying this integration process that we can study.
One of the most commonly studied vestibular phenomenon is known as velocity storage. If we suddenly start to spin participants at a constant rotational speed, the semicircular canals will initially respond to the onset of motion (as it is a sudden and large rotational acceleration) before decaying back to a resting state. Perceptually, participants typically report a sensation of spinning for much longer than their semicircular canals remain activated. This prolongation of the spinning sensation is known as velocity storage, and in understanding how the neural circuits drive velocity storage, we can form a better understanding for how sensorimotor neural processing occurs throughout the brain.
Chen A, Khosravi-Hashemi N, Kuo C, Kramer JK, Blouin JS. Development of a conversion model between mechanical and electrical vestibular stimuli. Journal of Neurophysiology. 2020 Feb 4. Link. Resources.