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Moallem, B. I.

Publications and source records attributed to Moallem, B. I..

2 recordsLinked to original sources
bioRxiv2026

Fear Learning Induced Brain Dynamics Predict Individual Extinction Memory Expression following Transcranial Magnetic Stimulation

Fear learning and extinction unfold as time-dependent processes. Herein, we examined how fear learning dynamically reorganizes brain activity immediately after learning, and whether such reorganization can be modulated with TMS application during extinction learning to prospectively predict extinction-memory expression. Eighty-seven healthy adults completed a three-day Pavlovian threat-learning protocol with resting-state fMRI acquired before and after conditioning (Day 1), dorsolateral prefrontal cortex (DLPFC) transcranial magnetic stimulation (TMS) applied during extinction learning (Day 2), and fMRI during extinction recall and renewal (Day 3). Using coactivation pattern analysis with a hidden Markov model within a 24-nodes threat-circuit parcellation, we identified a fear-learning-induced brain state characterized by global threat-circuit coactivation with heightened engagement and transition uncertainty post conditioning, and a progressive increase in engagement across post-conditioning. Critically, conditioning-induced functional connectivity reorganization within this state predicted individual differences in extinction recall- and renewal-related brain activation under TMS-modulated extinction (cross-validated; recall r = 0.47, p = 0.001; renewal r = 0.37, p = 0.01; permutation-tested), but not under natural extinction. Similar associations were observed between neural features and behavioral expression. These findings demonstrate that fear learning reshapes spontaneous brain-state dynamics and that such learning-induced reorganization serves as an interpretable biomarker for neuromodulation-linked extinction-memory expression.

neuroscience↗
bioRxiv2025

Neural Representation of Associative Threat Learning in Pulvinar Divisions, Lateral Geniculate Nucleus, and Mediodorsal Thalamus in Humans

Understanding the neural mechanisms underlying associative threat learning is essential for advancing behavioral models of threat and adaptation. We investigated distinct activation patterns across thalamic pulvinar divisions, the lateral geniculate nucleus (LGN), and the mediodorsal thalamus (MD) during associative threat learning using fMRI. The anterior pulvinar and MD exhibited parallel activation patterns, that may reflect distinct contributions to automatic and more deliberative learning processes. Additionally, our findings suggest a hierarchical functional organization of pulvinar activation during fear conditioning, in which coordinated activation among inferior, lateral, medial, and anterior divisions may support the integration of threat-related information. Pulvinar divisions and the MD showed activation during extinction learning and exhibited activation patterns consistent with salience processing during extinction recall and threat renewal. LGN activation patterns were consistent with feedforward visual processing. These findings extend current models of threat learning and memory by suggesting distinct patterns of thalamic involvement across associative threat learning and memory and providing a functional framework for investigating thalamic contributions to these processes.

neuroscience↗