Year: 2003
Type: dissertation
Abstract: The fusiform face area of the human brain is engaged in face perception and has been hypothesized to play a role in identifying individual faces [29].Functional magnetic resonance imaging (fMRI) of the brain reveals that this region of the temporal lobe produces a higher blood oxygenation dependent signal when subjects view face stimuli versus nonface stimuli [29].This thesis studied the way in which fMRI signals from voxels that comprise this region encode (i) the presence of faces, (ii) distinctions between different face types, and (iii) information about nonface object categories.Results suggest that the FFA encodes the presence of a face in one dominant eigenmode, allowing for encoding of other stimulus information in other modes.This encoding scheme was also confirmed for scene detection in the parahippocampal place region.PCA dimensionality suggests that the FFA may have larger capacity to represent information about face stimuli than nonface stimuli.Experiments reveal that the FFA response is biased by the gender of the face stimulus and by whether a stimulus is a photograph or line drawing.The eigenmode encoding of the presence of a face suggests cooperative and efficient representation between parts of the FFA.Based on the capacity for nonface versus face stimulus information, the FFA may hold information about both the presence and the individual identity of the face.Bias in the FFA may form part of the perceptual representation of face gender.
Author: Lakshminarayan Srinivasan
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2239737448