Prediction of verbal and numerical comprehension in patients following cochlear implantation.

Background: Cognitive abilities determine the outcome of cochlear implantat ion. Neuropsychological tests of intellectual, memory, attentional and emot ional functions were applied pre-operatively in 33 deaf patients receiving a cochlear implant. The outcome of verbal and numerical comprehension was m easured in a subgroup of 14 patients post-operatively and correlated with p re-operative neuropsychological performance. Methods: Neuropsychological pe rformance was recorded using standardized tests for intellectual abilities (abbreviated Wechsler Adult Intelligence Scale [WAIS], cristallized intelli gence scale), memory performance (Benton Visual Retention Test), attentiona l functions (d2 letter-cancellation-test), reaction time (Vienna Reaction T est) and emotional state (personality inventories). Verbal and numerical co mprehension was measured post-operatively following adaptation of the speec h processor. Performance and comprehension data were correlated. Results: C ognitive performance parameters did not differ significantly from those of a healthy group. There was a correlation of r = +0.65 between numerical com prehension and the ,,mosaic-test", a subtest of the WAIS and of r = +0.78 b etween numerical comprehension and the cristallized intelligence scale, Con clusions: Pre-operative cognitive parameters may predict the outcome of coc hlear implants.