BACKGROUND: Cognitive abilities like language, memory, reasoning, visualization, and perceptual functioning shape human action and are considered critical to the successful interaction with the environment. Alternatively, hearing loss can disrupt a child’s ability to communicate, and negatively impact cognitive development. Cochlear implants (CI) restore auditory input thereby supporting communication and may enhance cognitive performance. This study compares general cognitive development after cochlear implantation in two groups of children implanted earlier (age:4-6 years, N=22) and later (7-9 years, N=16) to the development of randomly selected normal hearing peers (N=48).DESIGN: Visualization, reasoning, memory, and attention were assessed using the Leiter-R scale at baseline (before implantation), and 8 months and 16 months post implantation for children with and without hearing loss RESULTS: Over the 16-month period, the cognitive improvement of 4-6 year old deaf children was greater than that of their normal hearing peers on all scales except for attention, while the improvement of 7-9 year olds was less major than that of their normal hearing peers on all scales. CONCLUSIONS: These results suggest that CI not only enhances communication skills but may improve cognitive functioning in deaf children. However, the extent of this improvement was dependent on age at intervention; current results demonstrated that the children received CI at young ages had better cognitive improvements.