[Cochlear implant and cerebral dominance].
On right handed people the right ear is considered to transmit speech information, and the left ear musical and cognitive information. These dominating ear properties are not exactly symmetrical in the left handed population, and are more consistent in females than in males. CI efficacy assessment is strongly based on speech intelligibility performances, because these criteria allow to measure the social reinsertion and communication possibilities. Consequently, one may ask if the relationship of the implanted side and the patient's handness could not be an important factor of this CI efficacy. We studied this relationship on 71 post-lingually deaf adult implantees. We measured patients handness using the Schachter's version of the so called Edimburg questionnaire described by Geschwind; this measurement has been moderated to take count of ambidextrous and mixed-handed population. Post operative performances has been assessed using the Francophone Protocol devoted to adults. We found that there is no significant correlation between these post-operative performances and the studied relationship. We estimate: 1) This absence of correlation is probably due to the high number of data which lead to determine the ear for implanting. 2) As far as this choice is feasible, dominating ear must nevertheless be elected, not only for theoretical reasons, but because the dominating hand may be easily employed for antenna adjustment. 3) As handness is strongly evident only after 4 y.o., and as left-handness seems to be more frequent on a congenitally deaf population, this choice is more problematic on less than 2 y.o. deaf children.