Ultrahigh Field fMRI Reveals Different Roles of the Temporal and Frontoparietal Cortices in Subjective Awareness
Journal of Neuroscience March 26, 2024 M. Poyo Solanas, Minye Zhan, Beatrice De Gelder
Whether conscious perception is an all-or-none or a gradual phenomenon depends on the brain region involved. In a 7T fMRI study, participants performed an emotion discrimination task under continuous flash suppression. Recognition sensitivity increased linearly with stimulus awareness, and threat stimuli slowed heart rate during near-clear perception. Brain activity in occipitotemporal, parietal, and frontal regions and the amygdala increased with awareness, while early visual areas showed the opposite pattern. Temporal area activity best fit a gradual model, whereas frontoparietal activity fit a dichotomous model. Specific experimental decisions, such as stimulus type and awareness evaluation method, significantly influence findings in consciousness research.