Auditory and visual refractory period effects in children and adults: an ERP study.

OBJECTIVE

This developmental study was designed to investigate event-related potential (ERP) refractory period effects in the auditory and visual modalities in children and adults and to correlate these electrophysiological measures with standard behavioral measures.

METHODS

ERPs, accuracy, and reaction time were recorded as school-age children and adults monitored a stream of repetitive standard stimuli and detected occasional targets. Standards were presented at various interstimulus intervals (ISIs) in order to measure refractory period effects on early sensory components.

RESULTS

As has been reported previously in adults, larger components for standards with longer ISIs were observed for an auditory N1 and the visual occipital P1 and P2 in adults. Remarkably similar effects were observed in children. However, only children showed refractory effects on the amplitude of the visual N1 and P2 measured at anterior sites. Across groups, behavioral accuracy and reaction time were correlated with latencies of auditory N1 and visual P2 across ISI conditions.

CONCLUSIONS

The results establish a normal course of development for auditory and visual ERP refractory period effects across the 6- to 8-year-old age range and indicate similar refractoriness in the neural systems indexed by ERPs in these paradigms in typically developing children and adults. Further, the results suggest that electrophysiological measures and standard behavioral measures may at least in part index similar processing in the present paradigms.

SIGNIFICANCE

These findings provide a foundation for further investigation into atypical development, particularly in those populations for which processing time deficits have been implicated such as children with specific language impairment or dyslexia.