Perceptual interference between regional accent and voice/speech disorders

We present a study where we examined the influence of a regional accent in the perception of voice and/or speech disorders. These aspects are most of the time overshadowed in clinical context. This protocol, involving multiple sources of speech variations, is also interesting for perception theories. For the experiment, speakers with or without a Southern French accent and with or without speech/voice disorders were recorded on reading a text. The samples were then randomly played back to two groups of listeners (familiar vs unfamiliar with the regional accent), specialists in speech therapy. The task was the perceptual evaluation of voice quality, articulation disorders and dysprosody. We focused in this paper on the voice dimension. The main results on this part concern the weak influence of regional accent on the perception of moderate or severe dysphonia, where the speech signal is strongly disturbed by the disorder. By contrast, the effect of regional accent is important on normal voices perception: listeners unfamiliar with the regional accent judge speakers with accent without voice disorder as slightly dysphonic. This last result can be interpreted as a form of perceptual interference between different dimensions of speech variations around a central position.