Biology subjects

Conway, B. R.

Publications and source records attributed to Conway, B. R..

5 recordsLinked to original sources

bioRxiv2026

Translating functional brain activity between humans and monkeys

Comparing brain responses across species is essential for identifying models of human cognition and testing theories of brain evolution, but differences in brain size, measurement techniques, and signal dynamics make it challenging. Here we collected dense fMRI data in macaques and humans using the same movies, static-image sequences, and tasks, and developed a multivariate analysis method that aligns neural representations temporally and spatially. The resulting data-driven framework provides a quantitative translation of brain responses among individuals and between species. Using this framework, we uncovered a broadly conserved cross-species hierarchy of retinotopic visual areas and whole-brain correspondence. Yet within this structure, we found that higher-order macaque areas shared more information with lower-order human areas, particularly during movies, providing evidence of species differences. We also identified potential macaque precursors to human regions involved in high-level cognition, including theory-of-mind and reading. These results offer a blueprint for common representational principles across species.

neuroscience↗

bioRxiv2025

The representation of object concepts across the brain

The mechanisms supporting concrete object concepts remain elusive. Here, macaque monkeys spent years learning object-concept primitives defined by color and shape. During fMRI, the monkeys held in mind one concept feature cued by the other. Using a whole-brain searchlight, we observed cross-feature decoding not in retinotopic cortex, but bilaterally in anterior inferior temporal cortex (aIT), temporal pole (TP), and frontal cortex (FC). Only TP and aIT had response patterns to concept shapes matching color-space geometry, and only PF had responses that decode behavioral errors. Two additional imaging experiments showed that color-associated versus non-color-associated shapes, and color-shape combinations congruent versus incongruent with the concepts, were distinguished only by extrastriate visual cortex, suggesting extrastriate cortex underpins color perception and perceptual feature binding. Together, the results provide a blueprint for how the brain generates stable object concepts and provides hypotheses for how conceptual representations engage perceptual representations through selective feedback during vision.

neuroscience↗

bioRxiv2022

Color and Spatial Frequency Provide Functional Signatures of Retinotopic Visual Areas

Primate vision relies on retinotopically organized cortex defined by representations of hemifield (upper versus lower visual field), eccentricity (fovea versus periphery), and area (V1, V2, V3, V4). To test for the functional signatures of these organizing principles, we used fMRI to measure responses to colored gratings with varying spatial frequency, color, and saturation across rentinotopically defined parcels in macaque monkeys. Using an approach we call Sparse Supervised Embedding (SSE), we identified stimulus features that differed most across the cortical parcels. Constraining the model according to each voxels eccentricity revealed the expected variation of spatial frequency and S-cone modulation with eccentricity. Constraining according to voxel dorsal-ventral location and retinotopic area, revealed two additional components which together provide unexpected functional signatures. First earlier visual areas were more sensitive to contrast and saturation compared to later areas. Second, ventral parcels responded less to luminance contrast and more to color, particularly along the orange-blue intermediate axis in cone-opponent color space. This dorsal-ventral asymmetry resembles differences between candidate dorsal and ventral subdivisions of human V4 but extends to include all retinotopic visual areas, with a magnitude that increased from V1 to V4. Overall, our study demonstrates SSE as a data-driven tool for generating hypotheses about cortical function and behavior, and provides insight into the functional roles of different retinotopic areas. Significance StatementThis study explores the functional roles of visual areas (V1, V2, V3, V4, V3a, MT) parceled by eccentricity preference and visual hemifield. We employ a new approach called Sparse Supervised Embedding (SSE), a promising technique for visualizing and understanding complex neuroimaging datasets. Analyzing fMRI responses to different color grating stimuli, we uncover a functional organization across these parcels, shedding light on their roles in visual computation. This study enhances our knowledge of processing in early visual cortex and how it varies across the retinotopic map. It also aids in resolving apparent differences between prior human and macaque studies.

neuroscience↗

bioRxiv2020

Uncovering the geometry of color space with magnetoencephalography (MEG)

The geometry that describes the relationship among colors is unsettled despite centuries of study. Here we present a new approach, using multivariate analyses of direct measurements of brain activity obtained with magnetoencephalography to reverse-engineer the geometry of the neural representation of color space. The analyses depend upon determining similarity relationships among the neural responses to different colors and assessing how these relationships change in time. To evaluate the approach, we relate patterns of neural activity to universal patterns in color naming. Control experiments showed that responses to color words could not decode activity elicited by color stimuli. The results suggest that three patterns of color naming can be accounted for by decoding the similarity relationships in the neural representation of color: the association of warm colors such as reds and oranges with "light" and cool colors such as blues and greens with "dark"; the greater precision among all languages in naming warm colors compared to cool colors; and the preeminence of red.

neuroscience↗

bioRxiv2020

Kidney single-cell atlas reveals myeloid heterogeneity in progression and regression of kidney disease.

The kidney has a limited capacity to repair following injury, however, the endogenous reparative pathways are not well understood. Here we employ integrated droplet- and plate-based scRNA-seq in the murine reversible unilateral ureteric obstruction model to dissect the transcriptomic landscape at the single cell level during renal injury and resolution of fibrosis. We generate a comprehensive catalogue of the changes induced during injury and repair, revealing significant myeloid cell heterogeneity, which would not have been identifiable by conventional flow cytometry. We identify new markers for the myeloid populations within the kidney as well as identification of novel subsets including an Arg1+ monocyte population specific to early injury and a Mmp12+ macrophage subset exclusive to repair. Finally, using paired blood exchange to track circulating immune cells, we confirm that monocytes are recruited to the kidney early after injury and are the source of Ccr2+ macrophages that accumulate in late injury. Our data demonstrate the utility of complementary technologies to identify novel myeloid subtypes that may represent therapeutic targets to inhibit progression or promote regression of kidney disease.

immunology↗