Findings from a recent study could represent a step toward developing new methods for measuring and tracking the severity of aprosody, or the lack of variations in speech, in schizophrenia, using acoustic phonetic parameters. Audio-recorded speech was obtained from 98 patients (including 25 with clinically rated aprosody and 29 without) and 102 unaffected controls using 5 tasks: 1 describing a drawing, 2 based on spontaneous speech elicited through a question (Tasks 2 and 3), and 2 based on reading prose excerpts (Tasks 4 and 5). Researchers compared groups on variation in pitch (F0), jaw/mouth opening and tongue height (F1) and tongue front/back position and/or lip rounding (F2), and intensity/loudness. They found:
- Regarding pitch variation, patients with aprosody differed significantly from controls in Task 5 in both unadjusted tests and those adjusted for sociodemographics.
- For the standard deviation (SD) of F1, no significant differences were found in adjusted tests.
- Regarding SD of F2, patients with aprosody had lower values than controls in Task 3, 4, and 5.
- For variation in intensity/loudness, patients with aprosody had lower values than patients without aprosody and controls across the 5 tasks.
Compton MT, Lunden A, Cleary SD, et al. The aprosody of schizophrenia: Computationally derived acoustic phonetic underpinnings of monotone speech. [Published online ahead of print February 12, 2018]. Schizophr Res. doi:10.1016/j.schres.2018.01.007.