Date on Master's Thesis/Doctoral Dissertation

5-2011

Document Type

Doctoral Dissertation

Degree Name

Ph. D.

Department

Psychological and Brain Sciences

Committee Chair

Molfese, Dennis L.

Committee Co-Chair (if applicable)

DeMarco, Paul J.

Author's Keywords

Neuropsychology; Motor observation; Motor imagery; Mirror neuron system

Subject

Neuropsychology; Motor ability; Eye-hand coordination

Abstract

Two major theoretical models, Direct Mapping and Functional Equivalence, suggest that the observation of action and imagery of action, respectively, involve activation of similar motor related areas. Despite the wealth of evidence that supports these two perspectives, the degree to which these motor-related actions overlap is still only vaguely defined. The present investigation sought to assess both the spatial and temporal characteristics of the brain activity involved in these motor related conditions. Specifically, the present study used ERP technology to assess the neural substrates of Motor Observation, Motor Performance, and Motor Imagery. Participants viewed images depicting two human grasping motions, whole hand grasping or precision finger-to-thumb grasping. Participants were to report, perform, or imagine performing the observed action depicted in the target image. Ongoing EEG was time-locked to the presentation of the target image. The EEG data were filtered, segmented, submitted to a series of artifact correction procedures, then averaged. Subsequently, the averaged data were subject a two-step sequential principal component analysis. These were then subjected to repeated measures ANOVAs. Additional analyses included amplitude and latency measures, obtained from selected regions across different conditions. These measures were compared and examined for group differences. In addition, Low Resolution Brain Electromagnetic Tomography was used to elucidate the underlying neural activity. Specifically, all three of the motor related experimental conditions were expected to show increased activation of motor related areas on the contralateral hemisphere (left hemisphere) to the instructed action, particularly in the Primary Motor Cortex and Primary Somatosensory Cortex, and increased activation in the Supplementary Motor Area, relative to a nonmotor control condition. However, the statistical analyses failed to support these hypotheses. In the end, a greater understanding of these processes through scientific advances further develops and improves both interventions and treatments aimed at bettering the lives of those suffering from a myriad of psychological, physical and psychophysical disorders resulting from many psychobiological causes including stroke, dismemberment, physical injury, and cognitive dysfunction. While the present study failed to further elucidate these neural mechanisms, this area of study is increasingly important and beneficial to wide ranging areas of medicine, neuroscience, and cognitive and sports psychology.

Download

Share

COinS