Abstract
The strength of each eye’s contribution to the visual percept, or ocular dominance, can be measured using binocular rivalry, which in turn can be modulated by attention. Interestingly, eye-specific voluntary attention can be modulated by monocular cueing (Zhang et al., doi: 10.1177/0956797611424289). Here we investigate whether directed attention to one eye using a monocular cueing task can modulate ocular dominance, as measured by binocular rivalry. We collected data from ten adults with normal vision over five sessions, each with four conditions: monocular cueing to the left eye, monocular cueing to the right eye, binocular cueing, and random cueing. Incompatible grating stimuli were presented to the participants’ two eyes. Throughout the task, participants used a joystick to continuously report which stimulus they saw, while making judgements about the cueing stimuli to direct attention to the cued eyes. The amount of time an eye’s rivalry stimulus is perceived throughout the duration of the task reflects the strength of that eye’s contribution to the visual percept. After averaging across conditions within each participant, the change in ocular dominance throughout the task was calculated. To ensure that the changes in ocular dominance were due to attention rather than the task, some participants did five sessions of two control conditions: no cueing and cueing without the task. No significant change in ocular dominance was found in these conditions. It appears that monocular cueing shifts ocular dominance the most toward becoming more balanced, and this effect is greatest when the weaker eye is cued. The effect was greatest in those who had large eye imbalances to begin with. This result suggests that directed attention to one eye using a monocular cueing task has the potential to correct binocular imbalances.