AI-driven modelling for cortex-wide neuromodulated learning

Lead Research Organisation: University of Bristol
Department Name: Computer Science

Abstract

Both animals and humans can learn cognitive tasks from sensory inputs. However, existing computational frameworks are extremely slow at learning such tasks. Therefore, a new generation of computational frameworks capable of rapid learning of cognitive tasks is urgently needed.
Here we propose that neuromodulation together with specific excitatory-inhibitory circuits enable efficient learning across multiple brain areas. Building on our expertise in developing biologically plausible AI-driven computational models of learning we will develop an adaptive synapse-to-behaviour model of neuromodulated cortex-wide learning. First, we will show that a precise neuromodulatory control of cell-types results in rapid brain-wide learning of cognitive tasks, but also in neural networks that are more robust to perturbations. Next, the predictions generated by the model will be tested using existing experimental data. We will test the model at the cellular, systems and behavioural level. Overall, the proposed integrative AI-driven computational framework, will be critical for our understanding of cortex-wide learning of cognitive tasks in both health and disease.

Technical Summary

Learning of cognitive tasks depends on behavioural feedback. In the brain this feedback is encoded by diffuse neuromodulators, such as those released by the Cholinergic system. These neuromodulators are believed to trigger learning by controlling circuits throughout the cortex. However, existing computational and conceptual frameworks of cortex-wide learning exhibit very slow learning, in sharp contrast with animal and human learning. This raises a fundamental question: how can the cortex learn rapidly using diffuse neuromodulation?

Here we propose that Cholinergic neuromodulation relies on specific excitatory-inhibitory circuits to assign credit efficiently to synapses throughout the cortex. Building on our expertise in developing AI-driven computational models, systems, cellular and synaptic neuroscience of cortical learning we will develop an adaptive synapse-to-behaviour model of neuromodulated cortex-wide learning. First, we will show that a precise control of cell-types results in rapid and more robust brain-wide learning of cognitive tasks, but also in task-encoding that are more robust to perturbations. Next, to demonstrate the plausibility of the model, it will be contrasted with recently acquired experimental data. We will first perform tests at the cellular level, by studying how feedforward and feedback cortical pathways should be controlled by the Cholinergic system. In addition, we will test our model at the systems level by comparing the control of inhibitory cell-types predicted by our model with imaging of the same cell-types during goal-driven learning in the cortex.
Overall, the proposed integrative AI-driven computational framework, will be critical for our understanding of cortex-wide learning of cognitive tasks in both health and disease.

Publications

10 25 50
 
Description This work has introduced computational theories by which cholinergic neuromodulation can control learning processes in the brain. Our theories suggest that it does so by controlling inhibitory cell-types.
Exploitation Route Our work suggests a means by which reward signals control learning processes. This could be taken forward by clinical and fundamental neuroscientists interested in repairing brain circuitry and addictions associated with dopamine and how it controls our perception of the world.
Sectors Healthcare

Pharmaceuticals and Medical Biotechnology

 
Description Modelling role of Cholinergic neuromodulation in cortical circuits 
Organisation Washington University in St Louis
Department School of Medicine
Country United States 
Sector Academic/University 
PI Contribution Our team has collaborated closely with the Kepecs Lab to model their data in the context of this grant proposal.
Collaborator Contribution Provided data and literature information to help constraint the model development.
Impact We are about to submit a manuscript, and we recently presented this work at the leading conference in the field, Cosyne 2024.
Start Year 2023