Neurocognitive risk in children with cochlear implants

Children who receive a cochlear implant (CI) for early severe to profound sensorineural hearing loss may achieve age-appropriate spoken language skills not possible before implantation. Despite these advances, reduced access to auditory experience may have downstream effects on fundamental neurocognitive processes for some children with CIs.

To determine the relative risk (RR) of clinically significant executive functioning deficits in children with CIs compared with children with normal hearing (NH).

In this prospective, cross-sectional study, 73 children at a hospital-based clinic who received their CIs before 7 years of age and 78 children with NH, with average to above average mean nonverbal IQ scores, were recruited in 2 age groups: preschool age (age range, 3-5 years) and school age (age range, 7-17 years). No children presented with other developmental, cognitive, or neurologic diagnoses.

Parent-reported checklist measures of executive functioning were completed during psychological testing sessions.

Estimates of the RR of clinically significant deficits in executive functioning (≥1 SDs above the mean) for children with CIs compared with children with NH were obtained based on 2 parent-reported child behavior checklists of everyday problems with executive functioning.

In most domains of executive functioning, children with CIs were at 2 to 5 times greater risk of clinically significant deficits compared with children with NH. The RRs for preschoolers and school-aged children, respectively, were greatest in the areas of comprehension and conceptual learning (RR [95% CI], 3.56 [1.71-7.43] and 6.25 [2.64-14.77]), factual memory ( 4.88 [1.58-15.07] and 5.47 [2.03-14.77]), attention (3.38 [1.03-11.04] and 3.13 [1.56-6.26]), sequential processing (11.25 [1.55-81.54] and 2.44 [1.24-4.76]), working memory (4.13 [1.30-13.06] and 3.64 [1.61-8.25] for one checklist and 1.77 [0.82-3.83] and 2.78 [1.18-6.51] for another checklist), and novel problem-solving (3.93 [1.50-10.34] and 3.13 [1.46-6.67]). No difference between the CI and NH samples was found for visual-spatial organization (2.63 [0.76-9.03] and 1.04 [0.45-2.40] on one checklist and 2.86 [0.98-8.39] for school-aged children on the other checklist).

A large proportion of children with CIs are at risk for clinically significant deficits across multiple domains of executive functioning, a rate averaging 2 to 5 times that of children with NH for most domains. Screening for risk of executive functioning deficits should be a routine part of the clinical evaluation of all children with deafness and CIs.