Assessing Spectral and Temporal Processing in Children and Adults Using Temporal Modulation Transfer Function (TMTF), Iterated Ripple Noise (IRN) Perception, and Spectral Ripple Discrimination (SRD)

Abstract

Purpose: The current study investigated maturational effects on auditory processing abilities using three psychophysical measures: temporal modulation transfer function (TMTF), iterated ripple noise (IRN) perception, and spectral ripple discrimination (SRD).Research Design: A cross-sectional study. Three groups of subjects were tested: 10 adults (18–30 yr), 10 older children (12–18 yr), and 10 young children (8–11 yr) Data Collection and Analysis: Temporal envelope processing was measured by obtaining thresholds for amplitude modulation detection as a function of modulation frequency (TMTF; 4, 8, 16, 32, 64, and 128 Hz). Temporal fine structure processing was measured using IRN, and spectral processing was measured using SRD. Results: The results showed that young children had significantly higher modulation thresholds at 4 Hz (TMTF) compared to the other two groups and poorer SRD scores compared to adults. The results on IRN did not differ across groups.Conclusions: The results suggest that different aspects of auditory processing mature at different age periods and these maturational effects need to be considered while assessing auditory processing in children.