Auditory ERPs and EEG abnormal findings in children with specific language impairment (SLI)

ERPs are under study in preschool children with specific language impairment (SLI). To characterize auditory ERPs and EEG features in preschool children. We studied 14 female and 18 male children (mean age 4.2 yrs). ERPs were obtained off-line from a continuous EEG recordings and with three different odd-ball paradigma of stimuli: syllabic, musical and natural (animal voice); automatic and manual, single sweep, average were compared; in five were detected focal fronto-temporal EEG paroxysms. Control group ERP: with syllabic and musical stimuli four stable peak were recorded: P1, N1, N2 and P2; with natural sound only P1 and N1. SLI patients: P1 peak increased in latency (148 ms; control 124 ms), but the P2 latency (398 ms) was shortened and stable compared with controls (419 ms). ERPs abnormalities suggested primary sensory cortical process disturbances, while precognitive and cognitive ERPs components were less affected. ERPs of the five patients with EEG abnormalities did not differ with the other patients, surprisingly indicating that EEG focal abnormalities did not affect language function and development. Nonetheless, to clarify the role of EEG focal paroxysms on SLI further integrated investigations are suggested given the poor spatial resolution of the method we used.