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Advanced Neurology





                                        ORIGINAL RESEARCH ARTICLE
                                        Evaluating the cognitive and

                                        electrophysiological plausibility of a thalamic
                                        computational model



                                        Ricardo Tiosso Panassiol *  and Francisco Javier Ropero Pelaez 1,2†
                                                             1†
                                        1 Department of Neuroscience and Behavior, Institute of Psychology, University of São Paulo, São
                                        Paulo, São Paulo, Brazil
                                        2 Center for Mathematics, Computing, and Cognition, Federal University of ABC, São Paulo, São
                                        Paulo, Brazil



                                        Abstract

                                        The thalamus acts as a gateway to the cortex, relaying information from the
                                        brainstem and spinal cord to cortical regions. Evidence suggests that thalamic
                                        networks play a role in pattern recognition by extracting key elements from sensory
                                        input.  We propose that thalamic networks function as a central orthogonalizer
                                        in  the  brain,  enabling  the  application  of  the  Hebbian  learning  rule  without
                                        contamination or “interference” between the correct output for one input pattern
                                        and the output for other input patterns. This study aims to describe a biologically
                                        plausible artificial neural network that mimics aspects of the physiological
                                        activity of the thalamic circuit. To validate this proposal, the network was tested
            † These authors contributed equally
            to this work.               in four different scenarios. The model successfully replicated electrophysiological
                                        processes, including: (i) inhibitory facilitation; (ii) waveform sculpting in reticular
            *Corresponding author:
            Ricardo Tiosso Panassiol    cells; (iii) pattern completion of thalamic input; and (iv) computational processing
            (ricardo.tiosso@usp.br)     of stabilized images on the retina. In human experiments, stabilized retinal
                                        images were perceived as sequences of patterns that appeared and disappeared
            Citation: Panassiol RT,
            Pelaez FJR. Evaluating the   suddenly. These patterns closely resembled or were related to the presented image,
            cognitive and electrophysiological   suggesting that they represent a mix of principal components derived from learned
            plausibility of a thalamic   images. Such components emerge when a complete image, or only a portion of it,
            computational model.
            Adv Neuro. 2024;3(3):3188.   reaches the thalamus. Our model effectively reconstructs images based on partial
            doi: 10.36922/an.3188       eye-to-thalamus information, mirroring human visual responses.
            Received: March 17, 2024
            Accepted: July 3, 2024      Keywords: Systems neuroscience; Computational modeling; Thalamic circuitry; Principal
                                        components; Hebbian learning
            Published Online: September 3, 2024
            Copyright: © 2024 Author(s).
            This is an Open-Access article
            distributed under the terms of the
            Creative Commons Attribution   1. Introduction
            License, permitting distribution,
            and reproduction in any medium,   At present, there is broad consensus on interpreting learning or the plastic changes that
            provided the original work is   occur in the brain in light of the Hebbian paradigm.  The idea that synaptic connections
                                                                                1,2
            properly cited.             are strengthened by the correlated activity of pre-synaptic and post-synaptic neurons
                                                                        3
            Publisher’s Note: AccScience   was first articulated by Hebb in 1948.  It gained strength in 1973 when Bliss and
            Publishing remains neutral with   Lömo  experimentally demonstrated that the processes described by Hebb occur in the
                                            4
            regard to jurisdictional claims in
            published maps and institutional   hippocampus. Today, the biological phenomenon most closely associated with Hebbian
            affiliations.               learning is long-term potentiation (LTP). 5
            Volume 3 Issue 3 (2024)                         1                                doi: 10.36922/an.3188
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