MMN to natural Arabic CV syllables: 1-normative data

Verification of the Mismatch Negativity (MMN) responses in normal adult subjects

Mismatch Negativity (MMN) is used to evaluate the central auditory system.

Aim

to characterize the MMN, in normal subjects.

Materials and Methods

prospective study, 12 subjects, six males and six females, between the ages of 18 and 24. “Mann-Whytnei” test. Exams: Pure Tone Audiometry (PTA), Tympanometry, Otoacoustic Emissions and Short and Long Latency Auditory Potentials (MMN).

Results

in MMN variable amplitude, the mean value was of −2.757 μV and −3.548 μV, CZA1 and CZA2; of 1.435 μV and −1.867 μV, CZA1 and CZA2. In variable and medium latency, we found in 150.7ms and 153.2ms, CZA1 and CZA2; in 170.4ms and 184.0ms, CZA1 and CZA2 - for females and males respectively.

Conclusion

related to latency, there was significant statistical difference between the genders in relation to CZA1 and CZA2; and it was lower for females and higher for males.

MMN to natural Arabic CV syllables: 2 – cross language study

Mismatch negativity response parameters; latency, amplitude, and duration - to natural Arabic and natural English CV syllables - were obtained from normal-hearing adult Egyptians, in two experiments. In the first experiment, MMN was obtained in response to English CV syllable paradigms (Ba-Wa) and (Ga-Da) differing in formant duration and start of third formant, respectively. In the second experiment, MMN response for Arabic paradigm (Baa-Waa), English paradigm (Ba-Wa), and for Arabic-English paradigm (Waa-Wa) was obtained. Results revealed that the three levels of speech representation; acoustic, phonetic and phonologic could be probed preattentatively by MMN. The acoustic properties of speech signal are processed earlier than the phonetic and phonologic properties.