Eye-movement-contingent control. Movements of the eyes control the release of visual and acoustic information. Visual and/or sound boundaries are pre-defined in the sentence for contingent control. When a reader's eye moves across the release boundary, a visual and/or speech signal is presented. In the following illustration table, visual/sound boundary are defined at space before `yellow' and `stripe' respectively. * indicates the fixation location; ( ) indicates the spoken duration.