Using naturally produced speech to elicit the mismatch negativity.

The mismatch negativity (MMN) was recorded from 10 young adults with normal hearing using naturally produced speech contrasts. Consonant-place and vowel-height contrasts were examined in consonant-vowel (CV) syllables by pairing either the consonant /t/ or /p/ with the vowel /I/ or /E/. Vowel-height was also examined as a pseudovowel; one cycle of the vowel segment of a CV was extracted and replicated over 200 msec. A total of five contrasts were examined: vowel-height following /p/, vowel-height following /t/, consonant-place preceding /E/, consonant-place preceding /I/, and pseudovowels. Significant MMN responses were elicited from all five contrasts, albeit with different amplitudes, latencies, and waveform morphology. The pseudovowel elicited the most well-defined MMN with the greatest amplitude and was found to be significantly different from the other four contrasts. Naturally produced speech stimuli appear to be viable stimuli for eliciting the MMN.