Cochlear Implant Benefits in Deafness Rehabilitation: PET Study of Temporal Voice Activations
Arnaud Coez 1*,
Monica Zilbovicius 2,
Evelyne Ferrary 3,
Didier Bouccara 3,
Isabelle Mosnier 3,
Emmanuèle Ambert-Dahan 4,
Eric Bizaguet 5,
André Syrota 6,
Yves Samson 7,
and
Olivier Sterkers 8
1 CEA-INSERM U797 Research Unit Neuroimaging and Psychiatry, Service Hospitalier Frédéric-Joliot, IFR49, Orsay, France; CEA, DRM, DSV, Service Hospitalier Frédéric-Joliot, Orsay, France; Laboratoire de correction Auditive, Eric Bizaguet, Paris, France; Université Paris-Sud 11, Paris, France
2 CEA-INSERM U797 Research Unit Neuroimaging and Psychiatry, Service Hospitalier Frédéric-Joliot, IFR49, Orsay, France; CEA, DRM, DSV, Service Hospitalier Frédéric-Joliot, Orsay, France
3 Inserm, Unit-M 867, Paris, France; AP–HP, Hôpital Beaujon, Service d'ORL et de Chirurgie cervico-faciale, Clichy, France; Institut Fédératif de Recherche Claude Bernard Physiologie et Pathologie, IFR02, Paris, France
4 AP–HP, Hôpital Beaujon, Service d'ORL et de Chirurgie cervico-faciale, Clichy, France
5 Laboratoire de correction Auditive, Eric Bizaguet, Paris, France
6 CEA, DRM, DSV, Service Hospitalier Frédéric-Joliot, Orsay, France
7 CEA, DRM, DSV, Service Hospitalier Frédéric-Joliot, Orsay, France; AP–HP, Hôpital Pitié-Salpétrière, Service Urgences cérébro-vasculaires, Paris, France; Université Pierre et Marie Curie Paris 6, Paris, France
8 Inserm, Unit-M 867, Paris, France; AP–HP, Hôpital Beaujon, Service d'ORL et de Chirurgie cervico-faciale, Clichy, France; Institut Fédératif de Recherche Claude Bernard Physiologie et Pathologie, IFR02, Paris, France; Université Denis Diderot-Paris 7, Paris, France
* To whom correspondence should be addressed. E-mail: acoez{at}noos.fr.
 |
Abstract |
|---|
Cochlear implants may improve the medical and social prognosis of profound deafness. Nevertheless, some patients have experienced poor results without any clear explanations. One correlate may be an alteration in cortical voice processing. To test this hypothesis, we studied the activation of human temporal voice areas (TVA) using a well-standardized PET paradigm adapted from previous functional MRI (fMRI) studies. Methods: A PET H215O activation study was performed on 3 groups of adult volunteers: normal-hearing control subjects (n = 6) and cochlear-implanted postlingually deaf patients with >2 y of cochlear implant experience, with intelligibility scores in the "Lafon monosyllabic task" >80% (GOOD group; n = 6) or <20% (POOR group; n = 6). Relative cerebral blood flow was measured in 3 conditions: rest, passive listening to human voice, and nonvoice stimuli. Results: Compared with silence, the activations induced by nonvoice stimuli were bilaterally located in the superior temporal regions in all groups. However these activations were significantly and similarly reduced in both cochlear implant groups, whereas control subjects showed supplementary activations. Compared with nonvoice, the voice stimuli induced bilateral activation of the TVA along the superior temporal sulcus (STS) in both the control and the GOOD groups. In contrast, these activations were not detected in the POOR group, which showed only left unilateral middle STS activation. Conclusion: These results suggest that PET is an adequate method to explore cochlear implant benefits and that this benefit could be linked to the activation of the TVA.
Key Words:
auditory cortex, hearing neuroimaging, hearing loss, temporal voice area
