Vectorized instructive signals in cortical dendrites during a brain-computer interface task

Gardado en:
Detalles Bibliográficos
Publicado en:bioRxiv (Jan 13, 2025)
Autor Principal: Francioni, Valerio
Outros autores: Tang, Vincent D, Toloza, Enrique Hs, Brown, Norma J, Harnett, Mark
Publicado:
Cold Spring Harbor Laboratory Press
Materias:
Acceso en liña:Citation/Abstract
Full Text - PDF
Full text outside of ProQuest
Etiquetas: Engadir etiqueta
Sen Etiquetas, Sexa o primeiro en etiquetar este rexistro!

MARC

LEADER 00000nab a2200000uu 4500
001 2886154931
003 UK-CbPIL
022 |a 2692-8205 
024 7 |a 10.1101/2023.11.03.565534  |2 doi 
035 |a 2886154931 
045 0 |b d20250113 
100 1 |a Francioni, Valerio 
245 1 |a Vectorized instructive signals in cortical dendrites during a brain-computer interface task 
260 |b Cold Spring Harbor Laboratory Press  |c Jan 13, 2025 
513 |a Working Paper 
520 3 |a Vectorization of teaching signals is a key element of virtually all modern machine learning algorithms, including backpropagation, target propagation and reinforcement learning. Vectorization allows a scalable and computationally efficient solution to the credit assignment problem by tailoring instructive signals to individual neurons. Recent theoretical models have suggested that neural circuits could implement single phase vectorized learning at the cellular level by processing feedforward and feedback information streams in separate dendritic compartments. This presents a compelling, but untested, hypothesis for how cortical circuits could solve credit assignment in the brain. We leveraged a neurofeedback brain computer interface (BCI) task with an experimenter defined reward function to test for vectorized instructive signals in dendrites. We trained mice to modulate the activity of two spatially intermingled populations (4 or 5 neurons each) of layer 5 pyramidal neurons in the retrosplenial cortex to rotate a visual grating towards a target orientation while we recorded GCaMP activity from somas and corresponding distal apical dendrites. We observed that the relative magnitudes of somatic versus dendritic signals could be predicted using the activity of the surrounding network and contained information about task-related variables that could serve as instructive signals, including reward and error. The signs of these putative teaching signals both depended on the causal role of individual neurons in the task and predicted changes in overall activity over the course of learning. Furthermore, targeted optogenetic perturbation of these signals disrupted learning. These results provide the first biological evidence of a vectorized instructive signal in the brain, implemented via semi independent computation in cortical dendrites, unveiling a potential mechanism for solving credit assignment in the brain.Competing Interest StatementThe authors have declared no competing interest.Footnotes* 1. Causal perturbation of dendritic activity disrupts learning. We found that the disruption of independent dendritic signals via optogenetic activation of layer 1 NDNF+ interneurons impaired learning, demonstrating the instructive role of the dendritic signals we observed for behavior (Figure 5h) 2. Optogenetic activation of NDNF+ interneurons disrupted reward-related information in apical dendrites of layer 5 neurons (Figure 4h-l). 3. L1 NDNF+ interneuron activation also abolished error-related information and signal vectorization in apical dendrites (Figure 5f-g). 4. Simultaneous multi-plane imaging to verify the specificity of NDNF+ IN activation on apical dendritic activity (Figure 3f-l). 5. We directly demonstrated that acute anesthesia strongly decreases the SD residual in a new cohort of mice. These experiments are a second, independent confirmation that the SD residual is a robust metric for somato-dendritic coupling and top-down signaling (Figure 3a-e). 6. Refocused the manuscript on vectorization. We believe that the shift from backpropagation broadens the relevance and appeal of our work, increasing its influence in the field. 7. Further contextualized our findings within the existing BCI literature. In the introduction, results, and discussion we added several passages which more specifically frame our findings within published BCI work. 8. We added a new Methods section to our manuscript to clarify the selection procedure for the neurons directly controlling the BCI. We also performed a new analysis to show how these neurons compare to the rest of the network on day 1 (Supplementary Figure 6b). 
653 |a Brain 
653 |a Implants 
653 |a Feedback 
653 |a Visual pathways 
653 |a Orientation behavior 
653 |a Computer applications 
653 |a Pyramidal cells 
653 |a Back propagation 
653 |a Assignment problem 
653 |a Dendrites 
653 |a Neural networks 
700 1 |a Tang, Vincent D 
700 1 |a Toloza, Enrique Hs 
700 1 |a Brown, Norma J 
700 1 |a Harnett, Mark 
773 0 |t bioRxiv  |g (Jan 13, 2025) 
786 0 |d ProQuest  |t Biological Science Database 
856 4 1 |3 Citation/Abstract  |u https://www.proquest.com/docview/2886154931/abstract/embedded/L8HZQI7Z43R0LA5T?source=fedsrch 
856 4 0 |3 Full Text - PDF  |u https://www.proquest.com/docview/2886154931/fulltextPDF/embedded/L8HZQI7Z43R0LA5T?source=fedsrch 
856 4 0 |3 Full text outside of ProQuest  |u https://www.biorxiv.org/content/10.1101/2023.11.03.565534v2