[Development of Auditory Processing and Perception Skills with and without APD in Primary School Age]

We examined two student age groups (1^st and 4^th class) in a control-group comparison whether the maturation processes of the central hearing system in typically developing children are also present in children with Central Auditory Processing Disorders (CAPD) at primary-school age.

The analyses included results of a behavioral test battery from 82 first graders (40 with CAPD; 42 healthy controls) and 65 fourth graders (35 with CAPD; 30 healthy controls). An ANOVA with the total value of the following 7 standardized examinations, and subsequently a MANOVA with the detailed test results were carried out: Speech (words) in Noise Recognition (Göttinger Sprachaudiometrie II); Dichotic Word Pair Understanding (Uttenweiler-Test); Heidelberger Phoneme Discrimination Subtests: Phoneme Discrimination, Phoneme Identification, Phoneme Analysis; the Subtest Auditory Sequential Memory for Digits of the Illinois Test of Psycholinguistic Abilities (German version); Mottier's Nonword Repetition Test.

The ANOVA showed significant main effects of "class" (1st versus 4th; p < 0.001, η² = 0.418) and "group" (CAPD versus healthy controls; p < 0.001; η² = 0.690), but no interaction effects between both. The result of the MANOVA was similar. Main effects, but only for two tests (phoneme identification; phoneme analysis) as well as the interaction of "class" and "group" were statistically significant, with statistically small effect sizes of 3 and 6 %.

Based on this cross-sectional study, the difference between the two study groups appears to be independent of the school class level.

At primary-school age, there is evidence of maturation of the central hearing system for both children with CAPD and healthy children.