Second formant transitions for acoustic analysis to differentiate among dementia types

Abstract

Recent evidence indicates that acoustic features associated with emotional prosody in speech may be an inexpensive, non-invasive method for differentiating among dementia types. In particular, frequency measures in the speech of people with dementia have been associated with listeners’ perception of emotional prosody. The purpose of this study was to determine if second formant (F2) transition information would enhance these differentiations. Prerecorded speech samples of Cookie Theft picture descriptions from 10 individuals with dementia of the Alzheimer’s type (DAT), 5 with vascular dementia (VaD), 9 with MCI, and 10 neurologically healthy controls (NHC) were obtained from the DementiaBank. Nine words that had initial obstruent consonants that occurred at least two times in each of the participant groups were selected for measurement. The F2 durations, extents, and slope were measured and analyzed. Across group comparisons revealed no pattern for F2 durations or extents. The fricatives had longer F2 durations than the plosives. Across word comparisons revealed significant differences across the consonant vowel combinations for all three measures. A group by word interaction occurred for the F2 slope with the VaD group exhibiting larger slopes than the other two groups.