Poster #: 125
Topic: Speech and language (incl. deficits)
Thursday, Sep 10, 2015
Perceptual asymmetry effects on the MMR to Danish speech sounds
1Center of Functionally Integrative Neuroscience (CFIN), Aarhus University, Aarhus C, Denmark
2Interacting Minds Centre (IMC), Aarhus University, Aarhus C, Denmark
3Dept. of Linguistics, Aarhus University, Aarhus C, Denmark
4Dept. of Cognitive Science, Aarhus University, Aarhus C, Denmark
Perceptual asymmetries in the mismatch response (MMR) to speech sounds have received little attention in the MMR literature. Furthermore, the effects of the immediate phonetic context on the MMR to speech sounds have not been investigated.
Using magnetoencephalography (MEG), we investigated native listeners’ MMRs to the phonetic contrast between [t] and [d] in Danish. We used both sounds as both deviants and standards in two different phonetic contexts: one preserving the contrast’s phonemic status ([CV]), and another neutralizing it ([VC]). This allowed us to examine perceptual asymmetries in the MMR to the [t]-[d] contrast, as well as effects of the immediate phonetic context on the MMR to the contrast.
We found a perceptual asymmetry effect on the MMR to the [t]-[d] contrast. Hearing [t] among [d]s elicited significantly stronger MMRs than hearing [d] among [t]s, regardless of the immediate sound context. We found no effects of the immediate phonetic context on the MMR. The asymmetry effect was mirrored in a behavioral oddball-detection task with a different group of native Danish listeners who showed reduced sensitivity for hearing [d] among [t]s. We discuss these results in relation to psychoacoustic accounts involving low-level feature detectors and the theory of phonological underspecification (FUL).