In partial fulfillment of the requirements for the degree of
Doctor of Philosophy in Applied Physiology
In the
School of Biological Sciences
Chase G. Rock
Will defend his dissertation
LEARNING AND TRANSFER OF HYPOGRAVITY ADAPTATION
ACROSS MOTOR AND COGNITIVE SYSTEMS
Tuesday, November 5, 2024
2:00 PM
Applied Physiology Building (555 14th St.), Room 1257
https://gatech.zoom.us/j/93650250168
Thesis Advisor:
Young-Hui Chang, Ph.D.
School of Biological Sciences
Georgia Institute of Technology
Committee Members:
T. Richard Nichols, Ph.D.
School of Biological Sciences
Georgia Institute of Technology
Gregory Sawicki, Ph.D.
School of Mechanical Engineering
Georgia Institute of Technology
Lewis Wheaton, Ph.D.
School of Biological Sciences
Georgia Institute of Technology
Lena Ting, Ph.D.
School of Biomedical Engineering
Georgia Institute of Technology and Emory University
ABSTRACT: The motor and cognitive systems are easy to think of as inhabiting different domains, but they overlap in many of their functions. Generally, motor learning has important cognitive components, and cognition makes use of motor areas of the nervous system. However, the specifics of the overlap between the motor and cognitive systems remain elusive. The goal of this set of experiments was to determine if different motor and cognitive systems share a single representation of gravity, or if gravity is accommodated separately by each system. Gravity was chosen due to its ubiquitous influence on motor action and cognitive predictions of movement. I hypothesized that gravity is represented in the nervous system in a generalizable way, such that adaptation in one gravity-dependent motor task will affect other, gravity-dependent motor actions, or even cognitive actions. To test this, three experiments were conducted, aimed at 1) characterizing the adaptation to simulated hypogravity jumping, 2) determining if gravity adaptation in jumping transfers to gravity-dependent arm movement, and 3) if the same gravity adaptation transfers to a gravity-dependent cognitive task. In support of my hypothesis, after participants successfully adapted to simulated hypogravity jumping, this adaptation then affected gravity-dependent arm movements as well as the cognitive task. The results support a shared representation of gravity between motor and cognitive systems that is adaptable and relies on accurate predictions of gravity-related sensory feedback, contributing to our understanding of transfer of learning and how abstract phenomena (like gravity) are managed by the neuromuscular system.