Emotional Prosody Perception and Production in Dementia of the Alzheimer's Type

Purpose: In this study, the authors investigated emotional prosody in patients with moderate Dementia of the Alzheimer's type (DAT) With Late Onset. It was expected that both expression and reception of prosody would be impaired relative to age-matched controls. Method: Twenty DAT and 20 control participants engaged in 2 expressive and 2 receptive tasks with randomly presented exemplars of sentences targeting the emotions of happiness, anger, sadness, and surprise. Results: In the expressive tasks, objective acoustic measurements revealed significantly less pitch modulation by the patient group, but these measurements showed that they retained the ability to vary pitch level, pitch modulation, and speaking rate as a function of emotion. In the receptive tasks, perception of emotion by the patient group was significantly inferior to the control group. Conclusions: Implications are discussed regarding impaired emotional prosody in DAT, and the utility of objective acoustic measures in revealing subtle deficits and overcoming methodological inconsistencies is emphasized. Further research is critical in advancing our understanding of this pervasive disorder and is important, clinically, in the provision of specific interventions.