Does visual frequency discrimination require attentional amplification?

Abstract The relationship between attention and consciousness is complex. Attention appears necessary for conscious processing of specific visual tasks or stimuli but not for others. In some tasks, visual attention can lead to a so-called interhemispheric advantage, where performance is better when stimuli are presented to both hemispheres, compared with when presented to a single hemisphere. It is still an open question whether the interhemispheric advantage and the interplay between attention and consciousness operate in similar ways across different sensory modalities. To improve our understanding of the relationship between attention and consciousness, we used a dual-task paradigm to investigate how attention impacts performance and conscious processing in a visual frequency discrimination task. Experiment 1 showed that a visual frequency discrimination task without distractors can be performed in the near absence of attention. However, experiment 2 revealed that the presence of distractors increases attentional demands. Surprisingly, and to the best of our knowledge, for the first time, experiment 2 demonstrated a dissociation between objective performance and metacognitive accuracy in the same task. Despite a reduction in the dual-task (divided attention) objective performance, metacognitive accuracy (participants’ insight into their own performance) remained intact and was equivalent to focused attention on a single task. No interhemispheric advantage was found. By comparing these results with past tactile experiments, this study provides indirect evidence to support that metacognition is domain-specific.