Short-Term and Working Memory Impairments in Early-Implanted, Long-Term Cochlear Implant Users Are Independent of Audibility and Speech Production.
OBJECTIVE
To determine whether early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated.


METHODS
Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions that differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing).


RESULTS
Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response.


CONCLUSIONS
Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory using phonological and linguistic strategies during memory tasks.
1Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana, USA; and 2Department of Psychiatry, Indiana University School of Medicine, Indianapolis, Indiana, USA.
Angela M
AM
AuBuchon
David B
DB
Pisoni
William G
WG
Kronenberger
D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D019929:Cochlear Implantation; D003054:Cochlear Implants; D003638:Deafness / Q000523:psychology / Q000534:rehabilitation*; D061345:Early Medical Intervention; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000523:psychology*; D008570:Memory, Short-Term; D011939:Mental Recall; D013068:Speech Production Measurement; D013997:Time Factors