Alzheimer's Disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are devastating neurodegenerative diseases that differentially affect socioemotional functioning. The proposed research examines two understudied facets of socioemotional functioning in these neurodegenerative diseases, cognitive and emotional empathy, using objective methods derived from basic affective science. Cognitive empathy is the ability to accurately understand another person's emotions through deliberative cognitive processing. Emotional empathy is the ability to share and respond to other's emotions through automatic affective mirroring process. Past research on empathy in neurodegenerative diseases has typically utilized informant reports susceptible to reporter bias, or emotion-labeling tasks that fail to capture the way emotions dynamically unfold during social interactions. Objective measures are needed that reflect patients' abilities to understand, share, and respond to other's changing emotions in real-time. In the current studies, cognitive empathy will be measured in the laboratory as patients' ability to accurately understand the changing emotional valence (negative to positive) of a character in a film clip over time. Emotional empathy will also be captured objectively in the laboratory by calculating patients' level of expressive and physiological responsiveness to their spouse's expressed affect during naturalistic social interactions involving conflict. Traditional informant reports and an emotion-labeling task will also be used for comparison. I will examine diagnostic differences in cognitive and emotional empathy in bvFTD, AD, and healthy control subjects (Aim 1) and determine the real- world longitudinal behavioral impact of empathy deficits (Aim 2). I will integrate laboratory measures of empathy with structural and functional neuroimaging data in order to identify the neural systems related to cognitive and emotional empathy impairment in bvFTD and hypothesized preservation of emotional empathy in AD (Aim 3). In addition, I will compare the neural correlates of our cognitive and emotional empathy tasks with those found for informant reports and an emotion-labeling task (Aim 3). The proposed dissertation research will prepare me to conduct interdisciplinary studies of emotion in neurodegenerative disease and to conduct future studies that detail the neuroanatomical bases of socioemotional dysfunction in various clinical disorders. This F31 will provide the support necessary to accomplish the following research goals: (1) to gain expertise in neurodegenerative disease, including neuroanatomy and differential diagnosis; (2) to become proficient in structural and functional connectivity neuroimaging analyses; and (3) to learn advanced statistical techniques for longitudinal and dyadic data analyses.
Delineating the precise empathy deficits occurring in various neurodegenerative diseases may prove useful for improving diagnosis. A better understanding of the longitudinal effect of empathic deficits on patients' social and neuropsychiatric functioning could elucidate predictors of behavioral changes in patients that are costly for society. Further, understanding the neurobiological correlates of empathy deficits may improve disease models for neurodegenerative and other disorders in which socioemotional deficits are a feature.
