Looking behavior in unconscious visual processing

During daily life, you encounter many visual stimuli. Even though most of what you see goes by without you being consciously aware of it, this does not mean that these stimuli are not able to affect your behavior. In two experiments, we investigated the effect of a visual object outside the observer’s consciousness on the oculomotor system of the observer, and how this is affected by the relevance of this visual stimulus. The relevance of the visual stimulus was manipulated with use of a memory task. Previous research showed that a relevant stimulus is favored, due to which for example the search behavior for the stimulus outside consciousness is more accurate, and the stimulus reaches consciousness faster, compared to a non-relevant stimulus. In both experiments, the observer was allowed to make eye movements. In the first experiment, the effect of the visual stimulus outside consciousness on the oculomotor system of the observer was investigated with use of CFS. However, contrary to previous research, the visual stimulus did not affect the oculomotor system, at least not in the first period of stimulus presentation. This difference is assigned to the addition of the memory task. The relevance of the stimulus could not be found to affect the oculomotor system. In the second experiment the bCFS paradigm was adopted to investigate whether it is possible to fixate at the visual stimulus without being consciously aware of the stimulus. This indeed seemed to be possible, but mainly during the first period of stimulus presentation. Again, the relevance was taken into account, but made no difference. The effect of relevance on breakthrough times is well-established by now, but also did not show in the second experiment. We explain these findings by a reset of CFS when the observer makes eye movements. Taken together, the effect of a visual stimulus outside the observer’s consciousness on his oculomotor system seems absent, for which the relevance of the stimulus makes no difference