
Online Lecture #3
🎙️ Speaker: Prof. Dr. Mark Latash, Pennsylvania State University
📅 Date: Thursday, 21st August 2025
⏰ Time: 12:00-14:00 CET
🖥️ Link to join
Topic: Structure of Motor variability as a Window into the Neural Control of Action
Biological movements involve numerous elements (joints, digits, muscles, neurons, etc.) at any level of analysis. This feature, addressed as motor redundancy, has been traditionally viewed as a source of computational problems for the brain. An alternative view, the principle of abundance, views the excess of elements as a powerful design that allows the brain to ensure and modify in a task-specific way dynamical stability of salient performance variables. The concept of uncontrolled manifold (UCM) as the solution space for a performance variable in a higher-dimensional space of elemental variables has been developed into a toolbox that allows to quantify features of action stability across tasks, spaces of analysis, and populations (including neurological patients). Its application has led to hypotheses on parallel action- stabilizing loops involving different neural circuitry. Recent developments include the analysis of intra-muscle performance- stabilizing synergies in spaces of individual motor unit firing frequencies, likely based on spinal circuitry, the analysis of synergies in spaces of hypothetical control variables (the reciprocal and coactivation commands) defined at different levels of the hierarchy, and exploration of the properties of the UCM.