Cross-modal re-organisation in adults with age related hearing loss (ARHL)

Sensory deprivation due to ARHL may result in the recruitment of cortical resources of the deprived modality by intact sensory modalities. This might have an impact on the outcome after hearing rehabilitation. 47 adults with a mean age of 67.77 years (SD 9.6) participated in this study. 18 had normal hearing thresholds (63.67, SD 7.8), 17 suffered of a mild to moderate (75.06 y., SD 8.1) and 12 of a severe to profound hearing impairment (75.06, SD 8.1) according to the WHO. Visual-evoked potentials were recorded by a 29-channel-EEG according to the 10-20 system during the presentation of a changing circle-star pattern and auditory evoked potentials while subjects listened to the syllable /ba/ at 65 dB SPL. Amplitude and latency of P100 and N100 were analysed.

Hearing thresholds had a strong impact on visual reorganisation (P08Diff, p= .024). A significant difference could be detected between severely (n=5) and profoundly hearing impaired (n=7) (p = .011). A negative correlation was observed between cross-modal visual re-organisation and speech comprehension assessed by the Freiburger monosyllabic speech test at 80dB 12 months after cochlea implantation (p= .025). Concerning the auditive task normal hearing subjects significantly differed to subjects with a mild-moderate hearing loss concerning the amplitude of the frontal electrode F3 (P100, p= .016).

Hearing loss leads to neuronal changes depending on the degree of hearing impairment. Cortical re-organisation might hamper speech outcome after hearing rehabilitation. This might be interesting with regard to the preoperative and postoperative counselling of CI-candidates.

Poster-PDF A-1027.pdf

Publication History

Article published online:
13 May 2021