Investigating the Performance of the Visual Oddball Paradigm in the Context of Facial Recognition

Abstract

The sequential visual oddball paradigm is a technique that is often used to elicit various components of cognitive event related potentials (ERPs). These components may serve as reliable biomarkers for neurodegenerative disorders such as Alzheimer's disease (AD). These disorders are significant health and economic burdens and monitoring such disease states may potentiate a higher quality of life for those affected. By improving upon current visual paradigm techniques, we can refine the methods in monitoring such disease states. The current study aimed to utilize electroencephalogram (EEG) on a cognitively healthy population of age 18-25 to assess the effects of modifying visual paradigm settings on the semantic processing of familiar faces. Due to the COVID-19 pandemic, the sample size was restricted to the researcher of the study. Six experiments, each involving five recorded trials, were executed in this study. These experiments included modifications to the type of visual stimulation in addition to the timing of visual stimulation. Visual stimulus types included familiar faces in the form of famous faces and self-faces. Timing was modified through stimulus duration and inter-stimulus intervals. When subject to different settings of the visual oddball paradigm, the results of this experiment consisted of late positive potential (LPP) components that were tested for a difference in their mean peak amplitude values. The results were obtained from channel-specific and ERP analysis. Independent t-tests were conducted to test for the effect of visual stimulus type. Analysis of variance (ANOVA) was conducted to test the effect of visual stimulation timing. Due to the limited sample size representing the target population, inferential claims regarding significance were not made from the findings of the investigation. The findings from this study, however, highlight potential insight that may be used to modify sequential visual paradigms to obtain a robust, cognitive method in eliciting ERP components.