Introduction: Mismatch Negativity (MMN) is an endogenous potential, which reflects the processing of difference occurring in the acoustic stimulus.
Objective: This work was designed to study the relationship between auditory processing and language deficits in children with specific language impairment (SLI) and compare their results with those of normal language development.
Patients and Methods: This study comprised 40 cases with SLI and 40 controls with normal hearing and language development in the age range 4-7 years. MMN was determined by subtracting the waves obtained by the stimuli 1KHz (frequent) and 2KHz (rare).
Results: There is no statistically significant difference between both groups regarding sex, chronological age, and IQ score. However, language age was statistically significant higher in the healthy controls than studied group (p < 0.001). All children in both groups had normal hearing. Phonological syntactic subtype of SLI was the most prevalent type in the study group. There was statistically significant difference in MMN latency and amplitude in SLI group when compared to normal control group (p < 0.001). Latency of MMN was more prolonged in SLI group than control group with lower amplitude in SLI group. Abnormal MMN test either abnormal latency or abnormal amplitude or both, was reported in 77.5% of SLI cases. Also, MMN was absent in 5 cases (12.5%) of SLI cases.
Conclusion: This data demonstrates that the language impairment in SLI children reflects underlying auditory processing deficits.