CORTICAL AUDITORY PROCESSING FROM CHILDHOOD TO ADULTHOOD: ASSOCIATIONS WITH SPEECH UNDERSTANDING.

Area of Science:

• Neuroscience
• Developmental Psychology
• Audiology

Background:

• Auditory system maturation is crucial for speech perception development.
• Developmental changes in cortical responses to speech sounds, especially frequency specificity, are not well understood.

Purpose of the Study:

• To investigate the developmental trajectories of early cortical responses (P1 and N1) to low- and high-frequency speech sounds.
• To examine the relationship between these neural responses and speech understanding abilities across different ages.
• To establish normative data for auditory development.

Main Methods:

• Electroencephalography (EEG) was used to record early cortical responses (P1 and N1).
• Sixty typically developing individuals aged 5-24 years were presented with low-frequency (/m/) and high-frequency (/s/) speech sounds.
• Associations between neural responses and speech perception in quiet and noisy conditions were analyzed.

Main Results:

• Distinct age- and stimulus-dependent patterns were observed in the developmental trajectories of P1 and N1 responses.
• Both linear and non-linear changes in neural responses were evident across development.
• Frequency-specific maturational profiles within the auditory cortex were identified.

Conclusions:

• The study delineates frequency-specific maturation of the cortical auditory system.
• Identified neurophysiological markers of speech perception can aid in assessing atypical auditory development.
• Provides a normative benchmark for understanding speech perception development.