Event Calendar

Join Dr. Jae Shun Kim (KNES, BIOE) as he hosts Dr. Mark L. Latash (The Pennsylvania State University) in the latest BBI Virtual Seminar. Dr. Latash's talk is titled, "Stability of Action and Perception, and an abstract is below.

A range of biological functions – from action to perception and to cognition – are based on abundant sets of relevant elemental variables. These variables are typically organized into synergies to ensure dynamical stability of salient outcome variables. Computational methods, such as analysis of inter-trial variance and of motor equivalence, have been developed within the framework of the uncontrolled manifold (UCM) hypothesis for analysis of action stability. The concept of iso-perceptual manifold (IPM) has been introduced to handle stability of percepts. The main findings include the following: (1) Humans ensure dynamical stability of performance by broadly varying contributions of elements (from motor units to large muscle groups and to hypothetical neural control variables), mostly constrained to the UCM; (2) In preparation to quick action, indices of stability drop 300-400 ms prior to the action initiation (anticipatory synergy adjustments); (3) Loss of stability is seen in the absence of visual feedback leading to unintentional and unperceived drifts of performance; (4) Perception of elemental variables is worse than perception of task-specific variables; (5) Proper functioning of synergies depends crucially on intact subcortical loops through the cerebellum and basal ganglia.

Feb 23, 2021 04:00 PM in Eastern Time (US and Canada)