Effects of Healthy Aging on Semantic Processing of Familiar Faces

Neurodegenerative disorders such as Alzheimer’s disease (AD) and mild cognitive impairment (MCI) remain significant health and economic burdens affecting millions worldwide. Developing affordable and accurate early diagnostic instruments for these disease states can contribute to the improvement of those patients’s quality of life by providing sufficient time for individuals to begin preventative pharmacotherapies before AD/MCI symptoms ensue. The current study aims to examine the subtle changes in electroencephalogram (EEG signals) recorded from a cognitively healthy population (n = 21) of varying ages (aged 20- 72) to assess the effects of normal, healthy aging on semantic processing of familiar faces. Analysis of the results demonstrated that age had a significant effect on event-related potential (ERP) components such as the latency of P600 at electrode Pz which had a negative correlation with age (p = -0.697). Results from scalp current density (SCD) analysis supported these findings indicating that the semantic process of familiar faces was faster among older groups while the overall cortex activation was more prominent among younger groups. The findings from this study highlight potential neural biomarkers that may be used to differentiate healthy elderly populations from those affected by AD and MCI.