Animals move smoothly and reliably in unpredictable environments. Models of sensorimotor control have assumed that sensory information from the environment leads to actions, which then act back on the environment, creating a single, unidirectional perception-action loop. This loop contains internal delays in sensory and motor pathways, which can lead to unstable control. We show here that these delays can be compensated by internal feedback signals that flow backwards, from motor towards sensory areas. Internal feedback is ubiquitous in neural sensorimotor systems and recent advances in control theory show how internal feedback compensates internal delays. This is accomplished by filtering out self-generated and other predictable changes in early sensory areas so that unpredicted, actionable information can be rapidly transmitted toward action by the fastest components. For example, fast, giant neurons are necessarily less accurate than smaller neurons, but they are crucial for fast and accurate behavior. We use a mathematically tractable control model to show that internal feedback has an indispensable role in achieving state estimation, localization of function -- how different parts of cortex control different parts of the body -- and attention, all of which are crucial for effective sensorimotor control. This control model can explain anatomical, physiological and behavioral observations, including motor signals in visual cortex, heterogeneous kinetics of sensory receptors and the presence of giant Betz cells in motor cortex, Meynert cells in visual cortex and giant von Economo cells in the prefrontal cortex of humans as well as internal feedback patterns and unexplained heterogeneity in other neural systems.
Shared representations in brains and models reveal a two-route cortical organization during scene perception
Department of Cognition, Development and Education Psychology, Faculty of Psychology, University of Barcelona（认知、发展与教育心理学系，心理学学院，巴塞罗那大学）；Institute of Neurosciences, University of Barcelona（神经科学研究所，巴塞罗那大学）；Bellvitge Institute for Biomedical Research（Bellvitge生物医学研究 institute）
Spin-Based Modeling of Perception as Emergent from contextualized Internal Evaluation
Istituto dei Sistemi Complessi (ISC-CNR)（复杂系统研究所）；Nirakara Lab, Institute of Research and Cognitive Science（认知科学研究所）；Department of Neurology, Institute of Neuroscience, Hospital Universitario Vithas Madrid La Milagrosa, Vithas Hospital Group（维塔斯马德里拉米拉格罗萨大学医院神经病学系、神经科学研究所）；Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC（马德里材料科学研究所）；Nanophotonics Technology Center, Universitat Politècnica de València（瓦伦西亚理工大学光子技术中心）
The effect of the excitatory feedback in anticipated synchronization and phase bistability regimes in neuronal populations
Universidade Federal de Alagoas（阿拉戈阿斯联邦大学）；Instituto de Física Interdisciplinar y Sistemas Complejos IFISC (CSIC-UIB), Universitat de les Illes Balears（巴利阿里群岛大学）；Florida Atlantic University（佛罗里达大西洋大学）
