Objective measurement of high-level auditory cortical function in children

Area of Science:

• Auditory Neuroscience
• Developmental Psychology
• Speech and Hearing Sciences

Background:

• Temporal processing is crucial for speech perception and language development.
• Assessing temporal processing in children can be challenging using traditional behavioral methods.
• Cortical auditory evoked potentials (CAEPs) provide an objective measure of auditory system function.

Purpose of the Study:

• To investigate the N2 latency of CAEPs as an objective indicator of temporal processing ability in children with normal hearing.
• To evaluate the sensitivity of N2 latency to different temporal processing paradigms.

Main Methods:

• N2 latency was measured using three paradigms: voice-onset-time (VOT) differences, speech-in-noise (CV/da/ in broadband noise with varying SNRs), and amplitude-modulated (AM) broadband noise.
• Thirty-four children aged 5-12 years with normal hearing and no speech, language, or reading impairments participated.
• Participants were divided into two age groups: 5-7 years and 8-12 years.

Main Results:

• N2 latency showed significant and systematic changes with variations in VOT and signal-to-noise ratio (SNR).
• The N2 latency differed significantly between the two amplitude-modulated broadband noise conditions.
• These findings indicate N2 latency's responsiveness to temporal acoustic changes.

Conclusions:

• The N2 peak of the CAEP serves as a sensitive objective measure for temporal processing in children, especially when an N1 peak is absent.
• N2 latency is a viable objective tool for assessing temporal processing in pediatric populations, including those with auditory processing disorders who are difficult to evaluate behaviorally.