Cochlear Implant Outcome and Functional Brain Organization in Deaf Subjects

ABSTRACT

Using different and adapted brain-imaging techniques in congenitally deaf children and postlingually deafened adults, we identified neural patterns that are consistently predictive of speech perception performance with a cochlear implant. Deaf subjects who show neural activity in ventral regions of the brain during deafness, whether to communicate or just when idling at rest, tend to become poor performers. By contrast, those who involve dorsal brain regions in the same cognitive situations tend to become good performers. We further show that cortical reorganization does not only reflect hearing loss and its duration, but also the functional relevance of the cognitive operations that are performed during deafness. We argue that the trajectory toward one or the other pattern of cortical activity could be controlled by appropriate cognitive training during the period of deafness preceding cochlear implantation.

KEYWORDS

Deafness - cognitive factors - cortical plasticity - reorganization - fMRI - PET

REFERENCES

• 1 Blamey P, Arndt P, Bergeron F et al. Factors affecting auditory performance of postlinguistically deaf adults using cochlear implants.  Audiol Neurootol. 1996;  1 (5) 293-306
• 2 Damen GW, Beynon AJ, Krabbe PF, Mulder JJ, Mylanus EA. Cochlear implantation and quality of life in postlingually deaf adults: long-term follow-up.  Otolaryngol Head Neck Surg. 2007;  136 (4) 597-604
• 3 Green KM, Bhatt YM, Mawman DJ et al. Predictors of audiological outcome following cochlear implantation in adults.  Cochlear Implants Int. 2007;  8 (1) 1-11
• 4 Lazard DS, Bordure P, Lina-Granade G et al. Speech perception performance for 100 post-lingually deaf adults fitted with Neurelec cochlear implants: comparison between Digisonic^® Convex and Digisonic^® SP devices after a 1-year follow-up.  Acta Otolaryngol. 2010;  130 (11) 1267-1273
• 5 Lee DS, Lee JS, Oh SH et al. Cross-modal plasticity and cochlear implants.  Nature. 2001;  409 (6817) 149-150
• 6 Doucet ME, Bergeron F, Lassonde M, Ferron P, Lepore F. Cross-modal reorganization and speech perception in cochlear implant users.  Brain. 2006;  129 (Pt 12) 3376-3383
• 7 Lee HJ, Truy E, Mamou G, Sappey-Marinier D, Giraud AL. Visual speech circuits in profound acquired deafness: a possible role for latent multimodal connectivity.  Brain. 2007;  130 (Pt 11) 2929-2941
• 8 Giraud AL, Lee HJ. Predicting cochlear implant outcome from brain organisation in the deaf.  Restor Neurol Neurosci. 2007;  25 (3-4) 381-390
• 9 Schorr EA, Fox NA, van Wassenhove V, Knudsen EI. Auditory-visual fusion in speech perception in children with cochlear implants.  Proc Natl Acad Sci U S A. 2005;  102 (51) 18748-18750
• 10 Lazard DS, Lee HJ, Gaebler M, Kell CA, Truy E, Giraud AL. Phonological processing in post-lingual deafness and cochlear implant outcome.  Neuroimage. 2010;  49 (4) 3443-3451
• 11 Andersson U, Lyxell B, Rönnberg J, Spens KE. Cognitive correlates of visual speech understanding in hearing-impaired individuals.  J Deaf Stud Deaf Educ. 2001;  6 (2) 103-116
• 12 Rouger J, Lagleyre S, Fraysse B, Deneve S, Deguine O, Barone P. Evidence that cochlear-implanted deaf patients are better multisensory integrators.  Proc Natl Acad Sci U S A. 2007;  104 (17) 7295-7300
• 13 Lee HJ, Giraud AL, Kang E et al. Cortical activity at rest predicts cochlear implantation outcome.  Cereb Cortex. 2007;  17 (4) 909-917
• 14 Thierry G, Giraud AL, Price C. Hemispheric dissociation in access to the human semantic system.  Neuron. 2003;  38 (3) 499-506
• 15 Toyomura A, Koyama S, Miyamaoto T et al. Neural correlates of auditory feedback control in human.  Neuroscience. 2007;  146 (2) 499-503
• 16 Rimol LM, Specht K, Weis S, Savoy R, Hugdahl K. Processing of sub-syllabic speech units in the posterior temporal lobe: an fMRI study.  Neuroimage. 2005;  26 (4) 1059-1067