High-resolution functional magnetic resonance imaging of perceptual expertise in the ventral temporal cortex at 7-tesla

Abstract

This dissertation aims to augment our understanding of the fine-grain neural architecture and functionality of object-selective regions of the ventral-temporal brain and, especially, the highly face-selective Fusiform Face Area (FFA). I begin in CHAPTER I with a brief discussion of the relevant literature, highlighting the ongoing debate regarding the modularity of face perception. CHAPTER II reports on Experiment 1 (E1), which includes a behavioral and a fMRI component. Behavioral measurements provide an index of individual differences in car and plane expertise, while the fMRI study tests the magnitude, selectivity and spatial extent of car and plane expertise effects within the lateral fusiform gyrus. E1 will primarily focus on the FFA and surrounding cortex, since the FFA is the center of the strongest arguments for modularity and the clearest predictions about expertise. CHAPTER III reports on Experiment 2 (E2) in which I measure behaviorally face and car expertise, and use fMRI to explore neural competition in the FFA and beyond. E2 will investigate the spatial distribution of expertise effects when car experts must simultaneous process multiple objects from expert and non-expert visual categories. Finally, in CHAPTER IV, I will offer a general discussion of E1 and E2. I will interpret the present findings in light of the research and propose new directions. For the rest of the dissertation, I will use “we” to describe the work I performed in collaboration with my advisor and collaborators at the Vanderbilt University Institute of Imaging Science.