Implementing Cortical Auditory Evoked Potentials in a Pediatric Audiology Clinic

By Elizabeth Grim and Stephanie Browning

This article is a part of the July/August 2021, Volume 33, Number 4, Audiology Today issue.

Cortical auditory evoked potentials (CAEPs) evaluate access to auditory stimuli at the level of the cortex. Although CAEPs are not often used clinically to evaluate and monitor a child’s auditory function, Hearts for Hearing (HFH), a private audiology clinic, has implemented a protocol for the use of CAEP testing to assist in the intervention plan. 

At HFH, CAEPs have been used to estimate auditory access primarily for children with auditory neuropathy spectrum disorder (ANSD) and children pre- and post-cochlear implantation. We have learned that CAEPs can be a useful tool for pediatric audiologists to assist in determining a plan of care and confirming auditory access for children for whom behavioral audiometry cannot yet be reliably completed.

The primary goal with CAEP testing is to assess maturation of the auditory system. The CAEP includes three landmarks: P1, N1, and P2. P1 originates from the primary auditory cortex. This response is typically robust in children, while N1 and P2 responses are often less robust until a child reaches age seven (Sharma et al, 2015). The P1 response can be elicited via click, tone-burst, or speech stimuli. 

FIGURE 1 depicts a P1 response obtained during clinical assessment of an HFH cochlear implant recipient three months post-activation. The latency of the response occurs between 50–300 msec post-stimulus onset, but varies as a function of age. For newborns, the latency of P1 is expected to be around 300 msec and will decrease significantly between one to three years of age until it reaches full maturation (50–60 msec), around ages seven to 10 years (Sharma et al, 2013).