Allophonic and phonemic perception

Allophonic and phonemic perception: a combined acoustic, behavioral and electrophysiological study investigated whether the phonological status of isolated vowels affects the computation at the cortical level. For this purpose two vocalic sound pairs of a Southern-Italian dialect (Tricase) were tested, one phonemic contrast, i.e. [e-i], and one allophonic variation [e-ɛ]. Importantly, the allophonic variation is due to the process of metaphony active in the dialect variety. Thus, also the allophones are not contrastive at the meaning level, they are part of the sound inventory of the dialect and therefore produced by the speakers in everyday communication. To test the pre-attentive perception of the vowel pairs, electroencephalographic recordings were carried out. In particular, the N100 and the mismatch negativity (MMN) components of the auditory event-related potential were analyzed to access the neural mechanisms related to auditory encoding, auditory sensory memory and language-specific abstract memory representations. To observe the attentive perception a same-different discrimination task was carried out to analyze the influence of the phonological function if attention is required. Finally, a group acoustic analysis was performed to figure out the acoustic cues and the phonological identity that characterize the analyzed vowels.