Content-specific activity in frontoparietal and default-mode networks during prior-guided visual perception González García, Carlos Flounders, Matthew Chang, Raymond Baria, Alexis T. He, Biyu J. How prior knowledge shapes perceptual processing across the human brain, particularly in the frontoparietal (FPN) and default-mode (DMN) networks, remains unknown. Using ultra-high-field (7T) functional magnetic resonance imaging (fMRI), we elucidated the effects that the acquisition of prior knowledge has on perceptual processing across the brain. We observed that prior knowledge significantly impacted neural representations in the FPN and DMN, rendering responses to individual visual images more distinct from each other, and more similar to the image-specific prior. In addition, neural representations were structured in a hierarchy that remained stable across perceptual conditions, with early visual areas and DMN anchored at the two extremes. Two large-scale cortical gradients occur along this hierarchy: first, dimensionality of the neural representational space increased along the hierarchy; second, prior’s impact on neural representations was greater in higher-order areas. These results reveal extensive and graded influences of prior knowledge on perceptual processing across the brain. 2025-01-22T12:59:29Z 2025-01-22T12:59:29Z 2018-07-18 journal article González-García, C., Flounders, M. W., Chang, R., Baria, A. T., & He, B. J. (2018). Content-specific activity in frontoparietal and default-mode networks during prior-guided visual perception. Elife, 7, e36068. https://hdl.handle.net/10481/100020 10.7554/eLife.36068 http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional