Seminar: 8/29 - Lena Ting
11:00 to 12:30 PM at:
Department of Biomedical Engineering, Emory University and Georgia Tech
"Individual differences in movements may reflect common neural processes for action and cognition."
Why can we recognize people at a distance by the way they walk? How do an individual's unique social, cultural, and biological influences shape how they move? What does this tell us about the interactions between the brain, body, and environment that shape us as individuals? Using a broad combination of computational and experimental techniques in neurophysiology and biomechanics I have created a new conceptual framework for understanding how complex and variable muscle activation patterns arise from interactions between the neural and musculoskeletal systems. For the first time, we are approaching a critical understanding of not only commonalities in movements across individuals, but also differences both within and across individuals which appear to be shaped by experience. I propose that general neural processes identified in cognitive processes such as speech, language, and social interactions are also inherent in motor tasks. No matter how primitive, neural systems make predictions and decisions in the face of uncertainty and ambiguity. Thus, the nervous system must contain stable representations of prototypical interactions with the environment—be they physical, social, cultural, or conceptual. For example, when speaking a new language, an individual’s performance is limited by the structure of his or her native language. The relative inflexibility of the categorization process by which sounds are represented in the nervous system leads to predictable biases in both perception and pronunciation—an accent. We have identified building blocks for motor tasks called muscle synergies that may contribute to each individual’s unique motor accent. We have used muscle synergies to characterize the structure of motor variability in individuals and we have identified common optimizing principles that shape the adaptation of muscle activity patterns in motor learning and motor deficit. Compared to “cost” of repeating a mispronounced word, “costs” of movements can be more readily quantified in terms of performance, energy expenditure, and biomechanics. By developing technologies simulate how individuals perform the motor tasks, we may be able to quantify how our unique motor accents reflect our culture, our perceptual and motor skill, and our neural circuits. As a neurophysiologist trained in mechanical engineering, this will be a highly speculative talk mean to encourage discussion, establish broad interdisciplinary collaborations and to identify areas of research in which I need to be educated.