Biology subjects

Branigan, N. K.

Publications and source records attributed to Branigan, N. K..

3 recordsLinked to original sources

bioRxiv2024

Computational Modeling of Proactive, Reactive, and Attentional Dynamics in Cognitive Control

We developed a novel Proactive Reactive and Attentional Dynamics (PRAD) computational model designed to dissect the latent mechanisms of inhibitory control in human cognition. Leveraging data from over 7,500 participants in the NIH Adolescent Brain Cognitive Development study, we demonstrate that PRAD surpasses traditional models by integrating proactive, reactive, and attentional components of inhibitory control. Employing a hierarchical Bayesian framework, PRAD offers a granular view of the dynamics underpinning action execution and inhibition, provides debiased estimates of stop-signal reaction times, and elucidates individual and temporal variability in cognitive control processes. Our findings reveal significant intra-individual variability, challenging conventional assumptions of random variability across trials. By addressing nonergodicity and systematically accounting for the multicomponential nature of cognitive control, PRAD advances our understanding of the cognitive mechanisms driving individual differences in cognitive control and provides a sophisticated computational framework for dissecting dynamic cognitive processes across diverse populations. Our integrative approach significantly advances psychological theory about the multiple neurocognitive processes underlying cognitive control. We also demonstrate the relevance of our theoretical and modeling framework to understand the cognitive, neural, clinical, and exposomic factors related to cognitive control.

neuroscience↗

bioRxiv2024

Nonergodicity and Simpson's paradox in neurocognitive dynamics of cognitive control

Nonergodicity and Simpsons paradox present significant, yet underappreciated challenges in neuroscience. Leveraging brain imaging and behavioral data from over 4,000 children and a Bayesian computational model of cognitive dynamics, we investigated brain-behavior relationships underlying cognitive control at both between-subjects and within-subjects levels. Strikingly, we observed a reversal of associations of inhibitory control brain activations with dynamic behavioral measures when comparing between-subjects and within-subjects analyses, revealing the nonergodic nature of these processes. This nonergodicity was pervasive throughout the brain but most pronounced in the salience network. Additionally, within-subjects analysis uncovered dissociated brain representations of reactive and proactive control processes, as well as distinct brain-behavior associations for individuals who adaptively versus maladaptively regulated cognitive control. Our findings offer insights into dynamic neural mechanisms of cognitive control during a critical developmental period. This work highlights the importance of embracing nonergodicity in human neuroscience, with implications for both theoretical understanding and applications to AI and psychopathology.

neuroscience↗

bioRxiv2023

Space wandering in the rodent default mode network

The default mode network (DMN) is a large-scale brain network known to be suppressed during a wide range of cognitive tasks. However, our comprehension of its role in naturalistic and unconstrained behaviors has remained elusive because most research on the DMN has been conducted within the restrictive confines of MRI scanners. Here we use multisite GCaMP fiber photometry with simultaneous videography to probe DMN function in awake, freely exploring rats. We examined neural dynamics in three core DMN nodes-- the retrosplenial cortex, cingulate cortex, and prelimbic cortex-- as well as the anterior insula node of the salience network, and their association with the rats spatial exploration behaviors. We found that DMN nodes displayed a hierarchical functional organization during spatial exploration, characterized by stronger coupling with each other than with the anterior insula. Crucially, these DMN nodes encoded the kinematics of spatial exploration, including linear and angular velocity. Additionally, we identified latent brain states that encoded distinct patterns of time-varying exploration behaviors and discovered that higher linear velocity was associated with enhanced DMN activity, heightened synchronization among DMN nodes, and increased anticorrelation between the DMN and anterior insula. Our findings highlight the involvement of the DMN in collectively and dynamically encoding spatial exploration in a real-world setting. Our findings challenge the notion that the DMN is primarily a " task-negative" network disengaged from the external world. By illuminating the DMNs role in naturalistic behaviors, our study underscores the importance of investigating brain network function in ecologically valid contexts. Significance statementOur research advances understanding of the default mode network (DMN), a brain network implicated in numerous neuropsychiatric and neurological disorders. In contrast to previous research examining immobilized subjects, we took the novel approach of investigating DMN function during naturalistic behaviors in freely moving rodents. Using a combination of multisite fiber photometry, video tracking, and computational modeling, we discovered a prominent role for the DMN in naturalistic real-world spatial exploration. Our findings challenge conventional views that the DMN is disengaged from interactions with the external world and underscore the importance of probing brain function in ecologically relevant settings. This work enriches our understanding of brain function and has important implications for pre-clinical investigations of disorders involving DMN dysfunction.

neuroscience↗