EEG studies of visual processing: Intra and inter-subject variability, saccades, and object recognition

This dissertation involves the use of the EEG (electroencephalogram) to study various aspects of visual processing. The first chapter describes the development of methods to quantify and visualize intra and inter-subject differences in the occipital response to pattern reversal. A main finding of the first chapter is that intra-individual and inter-individual variability in the visual evoked response and more generally all EEG studies is likely masked by intra and inter-individual differences in cortical folding. The second chapter presents regression based methods that can be used to determine the neural response to saccades of various sizes. The methods were used to determine saccade task size and saccade task dependent responses in various saccade tasks, including a visual search task. The third chapter investigates differences in the P300 EEG response in conditions wherein the subject is passively fixating versus conditions in which the object of interest is actively foveated via a saccade.