Barriers to Early Progress in Adult Cochlear Implant Outcomes.

Area of Science:

• Audiology
• Neuroscience
• Speech-Language Pathology

Background:

• Cochlear implant (CI) recipients exhibit variable speech perception outcomes.
• Peripheral (bottom-up) and neurocognitive (top-down) factors can limit CI user adaptation.
• Understanding these limiting factors is crucial for predicting and improving CI performance.

Purpose of the Study:

• To investigate the influence of peripheral and neurocognitive limiting factors on sentence understanding in quiet and noise.
• To assess the progression of speech perception over time in CI users.
• To validate a test battery for identifying limiting factors and correlate findings with early success criteria.

Main Methods:

• Retrospective analysis of 32 adult unilateral Nucleus CI users.
• Assessment of sentence recognition in quiet and noise at various time points (1 day to 2 years).
• Utilized a test battery including physiological measures (electrically evoked compound action potentials) and neurocognitive tests (Montreal Cognitive Assessment, Stroop Test, Reading Skills Assessment).

Main Results:

• 13/32 CI users achieved ≥90% sentence recognition in quiet at 1 month.
• Subjects without limiting factors were 8.5 times more likely to achieve ≥90% quiet recognition (p=0.010).
• Neurocognitive limiting factors were more prevalent (14/32) than peripheral factors (4/32); early scores predicted long-term performance.

Conclusions:

• Both peripheral and neurocognitive factors significantly affect early CI speech recognition.
• A ≥90% sentence recognition score in quiet at 1 month post-activation can indicate successful progress.
• Early performance assessment and identification of limiting factors are vital for tailoring rehabilitation and counseling.