Biology subjects

Kang, Y. H.

Publications and source records attributed to Kang, Y. H..

4 recordsLinked to original sources

bioRxiv2026

Predictive learning induces Bayesian cognitive maps in the hippocampus

Navigation requires perception: location must be inferred from noisy and ambiguous egocentric sensory inputs, as in visual estimation of distance. However, many classical models of spatial representation implicitly assume that allocentric location is directly observable, thereby neglecting perceptual uncertainty. Here, we compare such a model with a Bayesian ideal observer that explicitly incorporates perceptual inference. We find that the Bayesian observers beliefs over location more accurately reproduce key properties of place cell activity, including place field width, area, and density, within and across environments. Using analytic arguments and numerical simulations, we show that recurrent neural networks trained to predict the next egocentric sensory input learn representations resembling Bayesian beliefs and yield place cell-like activity in both familiar and unfamiliar environments, outperforming autoencoders trained to reproduce the current input. Together, these results suggest that hippocampal circuits may construct Bayesian cognitive maps from experience through predictive perceptual learning.

neuroscience↗

bioRxiv2023

Spatial uncertainty and environmental geometry in navigation

Knowing ones place in the world requires integrating sensory inputs with respect to the geometry of the environment. Consistent with this, variations in environmental geometry, such as the shape and size of an enclosure, have profound effects on navigational behavior1-4 and its neural underpinning in grid cells5-7. Here, we show that these effects arise as a consequence of a single, unifying principle: to navigate efficiently, the brain must maintain and update the uncertainty about ones location. We develop an image-computable Bayesian ideal observer model of navigation, continually combining noisy visual and self-motion inputs, and a neural encoding model representing the spatial uncertainty computed by the ideal observer. Critically, we find that a key determinant of spatial uncertainty is the dimensionality reduction inherent in the retinal projection of the environment. Mathematical analysis and simulations show that spatial uncertainty accounts for a diverse range of sometimes paradoxical distortions in human homing behavior across trapezoidal, stretched, and compressed environments. Moreover, the neural encoding of this uncertainty accounts for observed changes in grid field size, anisotropy, rescaling, and boundary-dependent tethering under analogous geometric manipulations. Our results show that spatial uncertainty arising unavoidably during navigation is key to understanding navigational behavior and its neural underpinnings.

neuroscience↗

bioRxiv2022

Group 3 Innate Lymphoid Cells are regulated by WASP in a microbiota-dependent manner

Wiskott-Aldrich syndrome protein (WASP) is a cytoskeletal regulator that is largely restricted to hematopoietic cells. While WASP expression in both lymphocytes and macrophages play a critical role in maintaining intestinal homeostasis, the function of WASP in innate lymphoid cells is unknown. Here we analyzed the role of WASP in the differentiation and function of group 3 innate lymphoid cells (ILC3s). WASP-deficient mice (Was-/-) have a marked reduction in ILC3s. Moreover, antimicrobial peptide expression in response to ILC3-derived IL-22 was also reduced in the absence of WASP. In Was-/- mice, we observed a reduction in CCR6+ ILC3s, cells known to restrict immune responses to commensal bacteria. WASP-deficient mice were more susceptible to Citrobacter rodentium, an enteric infection controlled by ILC3s. Interestingly, there was no reduction in ILC3s in Was-/- germ-free mice when compared to WT germ-free mice. ILC3s lacking WASP expression also demonstrated microbially-dependent alterations in gene expression associated with cell migration. Finally, ILC3-like (Rorgt+CD3-) cells were reduced in the GI tract of WASP-deficient patients. In conclusion, ILC3-specific expression of WASP is critical for the generation and function of ILC3s in the presence of commensal microflora. Aberrant ILC3 function in the setting of WASP-deficiency may contribute to underlying disease pathogenesis.

immunology↗

bioRxiv2020

Multiple decisions about one object involve parallel sensory acquisition but time-multiplexed evidence incorporation

The brain is capable of processing several streams of information that bear on different aspects of the same problem. Here we address the problem of making two decisions about one object, by studying difficult perceptual decisions about the color and motion of a dynamic random dot display. We find that the accuracy of one decision is unaffected by the difficulty of the other decision. However, the response times reveal that the two decisions do not form simultaneously. We show that both stimulus dimensions are acquired in parallel for the initial ~0.1 s but are then incorporated serially in time-multiplexed bouts. Thus there is a bottleneck that precludes updating more than one decision at a time, and a buffer that stores samples of evidence while access to the decision is blocked. We suggest that this bottleneck is responsible for the long timescales of many cognitive operations framed as decisions.

neuroscience↗