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arXiv · 2605.29355

Neural-Behavioral Representation of Natural Whole-body Movement in Monkeys

Abstract

Understanding how cortical activity represents natural whole-body behaviors in primates remains challenging. Limited by the diversity of movements and inaccessibility of large-scale neural representation of whole-body kinematics, previous motor decoding studies focused on constrained tasks and limited limb movements. Here, we present a neural-behavioral recording and modeling framework for freely moving monkeys, combining large-scale epidural cortical signals from distributed sensory- and motor-related areas with synchronized multi-view motion capture through a custom-made data collection platform. We reconstructed whole-body monkey kinematics and learned a compact behavior prior using an autoregressive encoder-decoder model. Conditioned on neural signals, the model decoded accurate and realistic whole-body movement without explicit physical constraints. Our results provide a novel proof-of-concept approach for decoding natural whole-body movements in primates using large-scale intracranial neural activity.

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Jieshi He, Puzhe Li, Yanan Sui, Mu-ming Poo. 2026-05-28. Neural-Behavioral Representation of Natural Whole-body Movement in Monkeys. https://arxiv.org/abs/2605.29355

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