bioRxiv Science⌕ Search

Biology subjects

Rogers, S. A.

Publications and source records attributed to Rogers, S. A..

3 recordsLinked to original sources

Differential modulation of aversive signaling by expectation across the cingulate cortex

Pain-related aversion is an affective-motivational state driven by sensory experience that promotes learning and recruits widespread cortical networks, yet how distinct cingulate subregions contribute to its adaptive utility remains poorly understood. Here we used longitudinal one-photon calcium imaging in mice to compare dynamics in the anterior cingulate cortex (ACC) and retrosplenial cortex (RSC) across repeated unsignaled foot-shocks and fear conditioning and extinction paradigm. Both regions contained relatively stable ensembles that responded robustly to shocks, indicating shared encoding of acute nociceptive events. However, only the RSC flexibly re-organized its population activity when shocks were preceded by predictive cues. These anticipatory dynamics in the RSC predicted the rate of fear learning across individuals and subsequent extinction. By contrast, the ACC maintained shock-responsive ensembles with limited cue modulation. Instead, its dynamics encoded decisions to freeze, aligning with its role in encoding ongoing nociception and driving immediate defensive behavior. Together, these results reveal a division of labor in which the ACC emphasizes ongoing nociceptive processing, while the RSC transforms sensory signals into predictive codes that shape learning and memory. This specialization highlights how distributed cortical computations cooperate to generate the adaptive value of aversion. More broadly, our findings suggest that these regions assume complementary roles to address immediate sensory-motivational responses while flexibly reconfiguring to support long-term behavioral adaptation. Significance statementPain engages widespread cortical circuits, yet how distinct cingulate subregions collaborate to shape its experience and utility remains unknown. Using longitudinal calcium imaging in mice, we demonstrate that both the anterior cingulate and retrosplenial cortex contain stable shock-responsive ensembles, but only the retrosplenial cortex flexibly remodels its activity when shocks are predicted by cues. These anticipatory dynamics not only predict fear learning but influence extinction. Our findings uncover a division of labor in which the anterior cingulate encodes ongoing nociception and immediate defensive actions, while the retrosplenial cortex transforms these signals into temporally structured representations that support learning and memory. This work highlights how specialized cortical computations interact to generate the adaptive value of pain.

neuroscience↗

Granular hydrogels as brittle yield stress fluids

While granular hydrogels are increasingly used in biomedical applications, methods to capture their rheological behavior generally consider shear-thinning and self-healing properties or produce ensemble metrics such as the dynamic moduli. Analytical approaches paired with common oscillatory shear tests can describe not only solid-like and fluid-like behavior of granular hydrogels but also transient characteristics inherent in yielding and unyielding processes. Combining oscillatory shear testing with consideration of Brittility (Bt) via the Kamani-Donley-Rogers (KDR) model, we show granular hydrogels behave as brittle yield stress fluids with complex transient rheology. We quantify steady and transient rheology as a function of microgel (composition; diameter) and granular (packing; droplet heterogeneity) assembly properties for mixtures of polyethylene glycol and gelatin microgels. The KDR model with Bt captures granular hydrogel behavior for a wide range of design parameters, reducing the complex transient rheology to a determination of model parameters. We describe the impact of composition on rheological behavior and model parameters in monolithic and mixed granular hydrogels. The model robustly captures self-healing behavior and reveals granular relaxation time depends on strain amplitude. This quantitative framework is an important step toward rational design of granular hydrogels for applications ranging from injection and in situ stabilization to 3D bioprinting.

bioengineering↗

Psilocybin-enhanced fear extinction linked to bidirectional modulation of cortical ensembles

The serotonin 2 receptor (5HT2R) agonist psilocybin displays rapid and persistent therapeutic efficacy across neuropsychiatric disorders characterized by cognitive inflexibility. However, the impact of psilocybin on patterns of neural activity underlying sustained changes in behavioral flexibility has not been characterized. To test the hypothesis that psilocybin enhances behavioral flexibility by altering activity in cortical neural ensembles, we performed longitudinal single-cell calcium imaging in the retrosplenial cortex across a five-day trace fear learning and extinction assay. A single dose of psilocybin induced ensemble turnover between fear learning and extinction days while oppositely modulating activity in fearand extinctionactive neurons. The acute suppression of fear-active neurons and delayed recruitment of extinction-active neurons were predictive of psilocybin-enhanced fear extinction. A computational model revealed that acute inhibition of fear-active neurons by psilocybin is sufficient to explain its neural and behavioral effects days later. These results align with our hypothesis and introduce a new mechanism involving the suppression of fear-active populations in the retrosplenial cortex.

neuroscience↗