The direct-realist theory of speech perception: counter-evidence from the analysis of the speech of a glossectomee

Abstract

This paper reviews data from a glossectomized subject—acoustic, articulatory, and perceptual—which appear to challenge the direct-realist theory of speech perception. Total tongue removal necessitates extreme compensatory articulation, and yet speech intelligibility remains good, at 58% overall. Several aspects of the glossectomee’s productions are particularly noteworthy: first, vocal tract activity in this case cannot be directly perceived. The glossectomee’s vocal tract does not move in the same way as a normal vocal tract and it is difficult to imagine how his articulatory gestures could be perceived without prior experience of his articulation. Second, the glossectomee regained intelligible speech despite the absence of any articulatory model to follow; the necessary compensations were spontaneous. Third, this subject retains his West Yorkshire accent; perception of this depends critically upon characteristic differences from standard British English in certain vowel qualities, which apparently are maintained in the acoustic or auditory pattern despite the impossibility of retaining the old articulatory gestural targets. These findings argue for pervasive cognitive mediation in the speech perception process, contra the direct-realist theory.