Psychoacoustic Testing to Assess the Functional Maturation of the Central Parts of the Auditory System

The age-appropriate morphofunctional formation of the central parts of the auditory system determines the normal trajectory of a child’s auditory and speech development. Impairments can lead to the emergence of central auditory processing disorders (CAPD) and associated problems of psychoverbal and general development. Psychoacoustic testing is quite informative and is the most accessible diagnostic tool for detecting signs of CAPD, including in pediatric practice; it can be performed from age four years as long as normative data for the relevant age groups are available. The aim of the present work was to carry out audiological assessments of the functional state of the central components of the auditory system using psychoacoustic methods in healthy children of different ages. Materials and methods. A total of 125 healthy full-term children aged 4–17 years with normal peripheral auditory function without hearing, speech, language, cognitive, or academic problems were examined. The children were divided into five age groups(years:months): 4:00–5:11; 6:00–7:11; 8:00–9:11; 10:00–11:11; 12:00 years and older. Along with traditional audiological examination, all children were given tests to assess the functional state of the central parts of the auditory analyzer: assessment of the perception of rhythmic stimulus sequences; the Random Gap Detection Test (RGDT); a monaural low-redundancy speech test in silence and on the background of noise interference; a binaural interaction test using alternating binaural speech; dichotic testing; testing using a simplified version of the Russian matrix sentence test in noise (RUMatrix). Results. Data on the sensitivity of the tests used in these studies assessing the functional state of different structures of the central part of the auditory system indicated that signs of maturation developed in the bottom-up direction as children aged. The pace of ontogenetic processes, assessed from the results of the corresponding tests, depended on subjects’ age groups. The morphofunctional development of the central part of the auditory system was found not to be complete by adolescence. Conclusions. The results obtained here can be used for differential diagnosis between immaturity of the central auditory system, CAPD, and hearing disorders and language disabilities of different types in children of different age groups.