ORIGINAL ARTICLE   

Otorinolaringologia 2018 December;68(4):138-47

DOI: 10.23736/S0392-6621.18.02165-3

Copyright © 2018 EDIZIONI MINERVA MEDICA

lingua: Inglese

Complex auditory brainstem response findings in cognitively impaired elderly

Tarek GHANNOUM ¹, Amany SHALABY ², Marwa FARGHALY ³, Mona HAMDY ¹, Hussein SHERIF HAMDY ¹ ✉

¹ Unit of Audiology, ENT Department, Kasr Al-Aini Hospital, Cairo University, Cairo, Egypt; ² Unit of Audiology, ENT Department, El Demerdash Hospital, Ain Shams University, Cairo, Egypt; ³ Department of Neurology, Kasr Al-Aini Hospital, Cairo University, Cairo, Egypt

BACKGROUND: Seniors often have more difficulty understanding speech than younger adults, particularly in noisy environments. Literature findings in complex auditory brainstem response (cABR) indicate that cognitive impairment coincides with changes in the neural representation of speech at multiple levels of the nervous system especially in the subcortical brainstem. Aims of work are to correlate objective auditory evoked potentials in form of complex auditory brainstem response with cognitive dysfunction.
METHODS: The study group comprised of fifty-one patients having cognitive impairment while the control group comprised of twenty healthy age and gender matched subjects. Both groups were subjected to: 1) full history taking and otologic examination; 2) full neurological examination; 3) full audiologic evaluation; 4) cognitive assessment; 5) behavioral central auditory processing battery and finally; 6) electro-physiologic assessment (complex auditory brainstem response (cABR).
RESULTS: A statistical significant difference was found between both groups in stimulus to response correlation (SR-r), envelope (F0), and response root mean square (RMS), but fine temporal structure (F1) was non-significantly different.
CONCLUSIONS: The key features of the cognitively impaired elderly in the cABR are: 1) reduced phase locking in form of reduced consistency of cABR waves; 2) delayed V, A, O latencies; 3) abnormal temporal processing; 4) reduced F0 amp (pitch encoding); 5) normal F1 amp (fine temporal structure). Also, reduced RMS amplitude (RMS amp) and reduced stimulus-response correlation were more pronounced in the cognitively impaired elderly as analyzed by MATLAB.

KEY WORDS: Auditory perceptual disorders - Cognition - Evoked potentials, auditory, brain stem