Biology subjects

Hoyos, P. M.

Publications and source records attributed to Hoyos, P. M..

4 recordsLinked to original sources

bioRxiv2026

Sulcal pleating captures functional boundaries in human visual cortex

The folding of the cortical sheet within the human brain is related to its functional organization at the level of major sulci and gyri. Yet how smaller folding features hidden within the two thirds of cortex buried in sulci may relate to functional specialization of the cortex is not clear. Using human visual cortex as a test bed, we identify four hidden brain folds within the major sulcus which spans the dorsal visual stream and demonstrate that their spatial consistency across individuals is related to functional boundaries of visual cortex. In separate observation and replication participant groups, we combine structural and functional magnetic resonance imaging to show that the boundaries separating the visual field maps comprising the dorsal stream can be predicted from these hidden gyri with an accuracy matching current probabilistic definitions of visual cortex. By further demonstrating that these hidden gyri colocalize with cytoarchitectonic regions of the human brain, and that the variability in their shape and size correlates with individual differences in visual behaviors known to rely on the dorsal stream, we provide evidence for a novel neuroanatomic framework which suggests that mesoscale pleating patterns of the cortex within human sulci are functionally and behaviorally relevant.

neuroscience↗

bioRxiv2026

Dorsal visual stream development improves symmetry of receptive field coverage and spatial attention

The dorsal visual stream is a large retinotopic network in human visual cortex, involved in attentional and spatial aspects of vision critical for attending to, filtering, and interacting with the visual environment. The visual field maps which comprise the dorsal stream have not been characterized across development; a fundamental gap in human neuroscience given this pathways role in critical childhood behaviors. Here, we designed a gamified task to retinotopically map the dorsal stream in both adults and children for the first time. We found that the dorsal representations of visual space undergo protracted development, increasing the area over which they pool information across the visual field. Children show an asymmetry in the way that receptive fields of each cerebral hemisphere tile visual space, with protracted development predominantly in the right hemisphere serving to balance coverage across the left and right sides of space. This divergence between the hemispheres developmental trajectories has behavioral relevance, with individual variability in visuospatial attention biases correlating with receptive field properties from childhood into adulthood.

neuroscience↗

bioRxiv2023

Shared architectural patterns across the human cortical mantle predict visual representations and capture behavior across the lifespan

The microstructure of cells within human cerebral cortex varies across the cortical ribbon, where changes in cytoarchitecture and myeloarchitecture are thought to endow each region of cortex with its unique function. While fine-scale relative to a cell, these changes at population level impact architectural properties of cortex measurable in vivo by noninvasive MRI, such as the thickness and myelin content of cortex. This raises the question of whether or not we can use these in vivo architectural measures to understand cortical organization, function, and development more broadly. Using human visual cortex as a test bed, we demonstrated two architectural gradients, one in which cytoarchitecture and myeloarchitecture converge and another in which they diverge. These two gradients underlie the structural and functional topography of visual cortex, even predicting the presence of new visual representations. Moreover, the two gradients show distinct visual behavior relevance and lifespan trajectory. These findings provide a more general framework for understanding human cortex, showing that architectural gradients are a measurable fingerprint of functional organization and ontogenetic routines in the human brain.

neuroscience↗

bioRxiv2023

Spatial processing of limbs reveals the center-periphery bias in high level visual cortex follows a nonlinear topography

Human visual cortex contains regions selectively involved in perceiving and recognizing ecologically important visual stimuli such as people and places. Located in the ventral temporal lobe, these regions are organized consistently relative to cortical folding, a phenomenon thought to be inherited from how centrally or peripherally these stimuli are viewed with the retina. While this eccentricity theory of visual cortex has been one of the best descriptions of its functional organization, whether or not it accurately describes visual processing in all category-selective regions is not yet clear. Through a combination of behavioral and functional MRI measurements, we demonstrate that a limb-selective region neighboring well-studied face-selective regions defies predictions from the eccentricity theory of cortical organization. We demonstrate that the spatial computations performed by the limb-selective region are consistent with visual experience, and in doing so, make the novel observation that there may in fact be two eccentricity gradients, forming a parabolic topography across visual cortex. These data expand the current theory of cortical organization to provide a unifying principle that explains the broad functional features of many visual regions, showing that viewing experience interacts with innate wiring principles to drive the location of cortical specialization.

neuroscience↗