Auditory Cortical Maturation in a Child with Cochlear Implant

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The central auditory nervous system starts its development in intrauterine life; however, its maturation persists lifelong. The first phase of development is independent of external neurosensory stimulation. However, the second phase will only be effective from the sensory inputs that will organize and direct the process of connections of neural networks development [1]. It is through sound stimulation that corticalmaturation is achieved, thanks to a phenomenon called neural plasticity: the ability to be modified in order to improve the cortical response front to environmental stimuli. Through these morphological (axon, dendritic, and synaptic structures) and functional (neuronal and synaptic physiology) changes, memory acquisition and subsequent learning become possible, reflecting behavioral changes with the development of auditory and language skills [2–4].

In cases where there is deprivation of sound stimulation, direct stimulation of the auditory nerve fibers through the cochlear implant (CI) has been an alternative for the CANS to receive the stimulation needed for the maturation process and, consequently, the development of auditory and oral language skills [5, 6]. Hence, after the surgical procedure and activation of CI electrodes, precise speech and language therapy is needed, aiming to monitor the development and maturation of central auditory pathways in order to validate the benefits of the rehabilitation process.

Thus, there are outcome measures, standardized and validated for Brazilian Portuguese, that are able to assess
the development of auditory and language skills of this population, providing important information that monitor
the rehabilitation process. Concerning objective methods, electrophysiological assessment of hearing, through analysis ofmorphology and latency of Long Latency Auditory Evoked