This project aims to determine which acoustic features of prosody (pitch, volume, duration) are affected the most by right or left hemisphere lesions and how this impacts perceived prosodic stress as determined by raters.

Prosody is the pattern of stress and tone used to emphasize language. It gives paralinguistic meaning to express emotion, intent, or significance. Recent evidence has indicated that this feature of language may be less lateralized than previously believed. This project aims to expand upon prior research by Ross et. al. that has suggested that the presence of aprosodic deficits alters specific acoustic parameters by using spoken English exemplars.

Using a database of spoken English from patients with ischemic strokes of the left or right hemisphere we have isolated acoustic parameters (pitch, volume, and syllable duration) that are impacted by lesions of the left or right cerebral hemisphere and had raters evaluate the level of perceived emphasis in the audio samples. We then used linear regression analyses to model Stress Prominence with the various acoustic measures serving as independent variables. This data will be correlated with the amount of emphasis perceived by raters.

There is no single salient acoustic feature of prosodic stress. Linguistic requirements likely determine which acoustic parameters speakers utilize to produce emphasis. The left and right hemisphere contribute to the expression of prosody in different and likely equally critical ways.