This brief study has two essential aims. First, it is directed toward the measurement of changes in voice control that may be consequent on the overnight deactivation of cochlear implants (CIs) by individual young children in a residential school for the deaf. Second, the work is based on the exploratory use of a set of voice analytic procedures that, although developed in the first instance for work on connected speech with hearing-impaired children, have subsequently been applied extensively in voice clinic environments. Acoustic and electrolaryngograph speech recordings have been made and analyzed for a group of children with CIs, early in the morning with acoustic and CI aids switched off and at the end of a normal day's use. Special attention has been paid to the analysis of perceptually relevant physical aspects of pitch, intonation, and voice quality. Differences in voice control between these conditions of implant use have been found for all of the children. Copyright © 2011 by Thieme Medical Publishers, Inc.