Results of a national multicenter assessment concerning a new proposed fast SRT50 test to quickly assess the real impairment of deaf patient in noise before (and after) surgical functional otologic surgery

The effectiveness of cochlear implants (CIs) is largely dependent on the capacity of the central auditory system to adapt and reorganize in response to artificial electrical stimulation. This neural plasticity is essential for the accurate interpretation of speech signals in CI users. Repetitive transcranial magnetic stimulation (rTMS), particularly when targeted to the auditory temporal cortex, has shown promise as a neuromodulatory intervention capable of enhancing such plasticity. In this context, the present pilot study explores the potential of rTMS to modulate early auditory processing, as measured by the Frequency-Following Response (FFR)—a neurophysiological marker of the brain's ability to encode complex acoustic signals.

This study aims to assess whether high-frequency rTMS (10 Hz) applied over the left temporal cortex in adult CI users can influence the neural encoding of both consonant and vowel stimuli—specifically /da/, /ga/, /ba/, and /ia/—as indexed by changes in FFR measures. The broader goal is to determine whether this modulation may contribute to improved speech perception outcomes in individuals with limited CI experience.

Participants within the first 12 months of CI activation are randomized into two groups: active rTMS combined with auditory rehabilitation, and sham stimulation with rehabilitation. FFRs are recorded in response to synthetic syllables representing transient (/da/, /ga/, /ba/) and steady-state (/ia/) stimuli at three time points: baseline, immediately post-intervention, and one month later. Complementary behavioral assessments include speech-in-noise perception (via the Italian Matrix Test), auditory working memory tasks, and patient-reported outcome measures to evaluate listening effort and quality of life.

It is anticipated that participants receiving active rTMS will exhibit enhanced phase-locking and neural synchrony, particularly in encoding the fundamental frequency (F0) and formant trajectories of speech sounds. These changes would reflect a positive modulation of auditory brainstem and cortical responses, supporting the hypothesis that rTMS can facilitate auditory neural plasticity in CI users.