Energy efficient synaptic plasticity
Abstract
Many aspects of the brain's design can be understood as the result of evolutionary drive towards metabolic efficiency. In addition to the energetic costs of neural computation and transmission, experimental evidence indicates that synaptic plasticity is metabolically demanding as well. As synaptic plasticity is crucial for learning, we examine how these metabolic costs enter in learning. We find that when synaptic plasticity rules are naively implemented, training neural networks requires extremely large amounts of energy when storing many patterns. We propose that this is avoided by precisely balancing labile forms of synaptic plasticity with more stable forms. This algorithm, termed synaptic caching, boosts energy efficiency manifold and can be used with any plasticity rule, including back-propagation. Our results yield a novel interpretation of the multiple forms of neural synaptic plasticity observed experimentally, including synaptic tagging and capture phenomena. Furthermore our results are relevant for energy efficient neuromorphic designs.
Data availability
Simulation scripts can be found at https://github.com/vanrossumlab/li_vanrossum_19.
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Data from: The MNIST database of handwritten digitsThe MNIST database of handwritten digits.
Article and author information
Author details
Funding
Leverhulme Trust (RPG-2017-404)
- Mark CW van Rossum
Engineering and Physical Sciences Research Council (EP/R030952/1)
- Mark CW van Rossum
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Li & van Rossum
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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