• Cortical representations of cochlear implant stimulation are shaped by electrode configuration, stimulation spread, and inter-electrode interactions, yielding diverse activation patterns and rapid plasticity across users and species as stimulation parameters and electrode placement vary. [17], [15], [19], [12].

• Engineering and stimulation strategy advances—multichannel high-rate pulsatile stimulation, apical electrode design, and optimized input levels—link device physics to perceptual outcomes, influencing speech understanding and safety margins in CI users. [10], [9], [11].

• Clinical trajectories and predictors of outcome emerge across ages, with preoperative factors, implant age, and rehabilitation pathways shaping long-term speech, language, and social development in children and adults. [2], [6], [5], [20], [18], [8].

• Cross-modal neural processing and sensory integration in CI users are evidenced by visual contributions to speech comprehension and cortical encoding of CI stimuli, pointing to multimodal neural mechanisms supporting perception. [16], [17], [12].