This research addresses concerns in an NIH PAR, ?Emotional Function in Normal Aging and/or MCI and AD/ADRD?. It expands on foundational research in order to clarify the trajectories of change in emotional processing and linked neurobiological factors in adults who are aging normally, as well as in individuals with Mild Cognitive Impairment (MCI) and Alzheimer?s disease (AD). Its goals focus on 1) normative maturational shifts in emotional processing, and 2) how dysfunction in the integrative neural-behavioral mechanisms of emotional function manifest in MCI and the early stages of AD/ADRD. We propose to study brain Event- Related Potentials (ERPs) in the context of affective processing of word stimuli based on the classic, quantitative three-dimensional theory of affective (emotional) meaning developed by C.E. Osgood. Can the emotional changes which accompany aging be elucidated by brain ERPs measured during processing of affective word stimuli? What are the relationships among our ERP and behavioral measures and our neuropsychological measures of cognitive ability and neuropsychiatric assessments of affect and emotion? These questions will be studied in young adults, in elderly with normal cognition, and in like-aged individuals afflicted with MCI and early-stage AD. In addition, we will examine how affective meaning in ERPs change in MCI/early-stage AD when compared with like-aged normal elderly. Also studied will be the effects of gender differences on affective meaning ERP measures both in the aging analyses and the cognitive impairment analyses of MCI/AD. Our experimental design builds on a strong, empirically-supported framework of affective processing and emphasizes the affective differences within Osgood?s model. Multivariate analysis methods will be utilized, including separately studying combinations of ERP components related to particular connotative word classes for men and for women.
Alzheimer?s disease (AD), a persistent and devastating dementing disorder of old age, is a major public health burden whose impact is rising dramatically with the burgeoning aging population. This study will examine brain Event-Related Potentials (ERP) as useful functional components to measure normal aging and AD-related changes in affective (emotional) word processing. These ERPs are noninvasive, relatively inexpensive, directly related to brain activity, and may act as surrogate measures of affective changes due to AD.