A ๐๐ช๐๐ ๐ฉ๐๐๐ฃ๐ ๐จ to my supervisors & co-authors @cianodonnell.bsky.social , John Wade & @conjh.bsky.social !
We are excited for what these principles imply both for understanding the brain & for designing more robust AI.
Posts by James McAllister
Lyapunov dimension of dynamics
๐ง๐ต๐ฒ ๐๐ฟ๐ฎ๐ฑ๐ฒ-๐ผ๐ณ๐ณ: The efficiency & robustness comes with a price. We found biological wiring leads to lower-dimensional, less expressive dynamics.
We find that neuron self-recurrency is a key feature which stabilises spectral properties & dynamics, inducing robustness to node loss & hyperparameter variation.
Relative spectral radius under random pruning
๐ฅ๐ผ๐ฏ๐๐๐๐ป๐ฒ๐๐: CoNNs also proved to be significantly more resilient to:
- node loss, maintaining performance & spectral radius under pruning longer than conventional random networks
- parameter perturbation, where CoNNs better maintained critical dynamics & smoother dynamical transitions.
Crucially, we found that specific structural features (like self-loops, clustering, and node degree) correlated with task engagement, meaning the network's physical structure directly shapes how neurons share the workload!
Participation ratios of neural engagement distributions
๐๐ณ๐ณ๐ถ๐ฐ๐ถ๐ฒ๐ป๐ฐ๐: We found that CoNNs generally achieved comparable task performance to classic Echo State Networks, but with lower โwiring costsโ (smaller weights) & lower โenergy demandsโ (reduced neural activity).
CoNNs also showed more specialised engagement (smaller subsets of contributing neurons).
Constructing connectome-based neural networks
Really excited to share a new preprint!
๐๐ผ๐ ๐ฑ๐ผ ๐ฏ๐ฟ๐ฎ๐ถ๐ป๐ ๐๐๐ฎ๐ ๐ฟ๐ผ๐ฏ๐๐๐ & ๐ฒ๐ณ๐ณ๐ถ๐ฐ๐ถ๐ฒ๐ป๐ ๐๐ต๐ถ๐น๐ฒ ๐ฏ๐ฒ๐ถ๐ป๐ด ๐ถ๐ป๐ฐ๐ฟ๐ฒ๐ฑ๐ถ๐ฏ๐น๐ ๐๐ฝ๐ฎ๐ฟ๐๐ฒ? We explore how!
www.biorxiv.org/content/10.6...
We built Connectome-based Neural Networks (CoNNs) using Drosophila wiring (larva&adult) & compared with random networks with same sparsity.
Excited to read this!
Non-random brain connectome wiring enables robust and efficient neural network function under high sparsity
www.biorxiv.org/content/10.6...
Non-random brain connectome wiring enables robust and efficient neural network function under high sparsity www.biorxiv.org/content/10.64898/2026.03...
New preprint from the lab on synapse development in the nascent neocortical hierarchy!
Using mice that label MAGUK proteins developed by Seth Grant we find key differences in the laminar maturation of association and sensory motor cortices, including delayed, cortex-wide maturation of L1 synapses.
Region- and layer-specific glutamatergic synapse development in the nascent cortical hierarchy www.biorxiv.org/content/10.64898/2026.02...
Will this be available in the UK or EU? :)
Photo of James McAllister from Ulster University giving a presentation on his work on brain-inspired reservoir computing
Lovely time today at the 2nd All-Ireland Computational Neuroscience Symposium at Queens U Belfast. It's a small but growing community on the island. imo the talks were all genuinely great and I'm really excited for the future
Round 3 back in Dublin next August apparently if anyone wants to join! โ๏ธ๐ง
This is so fab! What a brilliant resource, thanks John!
Very well done!
@camneuro.bsky.social our amazing PhD student James McAllister is giving a talk at 2pm in CBL on drosophila-larva connectome-based recurrent neural networks
talks.cam.ac.uk/talk/index/2...
This makes me very happy!
Amazing, thank you so much! And thanks for such an awesome network tool.
Thank you!
I was using graph-tool (it's fabulous btw!) in Colab a month or so ago and it worked perfectly, but it now is complaining at the part "from graph_tool.all import *" saying "ModuleNotFoundError: No module named 'graph_tool'"...is there something that hasn't yet been updated in Colab? Thanks!
This is a great write-up of a brilliant paper! :)
Schematic diagram of reservoir computing neural network, with drosophila larva connectome overlaid as reservoir connectivity.
Delighted @jajmca.bsky.social's abstract was accepted for COSYNE 2025, for his work on linking neural circuit structure to function via drosophila-connectome-based reservoir computing. With @conjh.bsky.social, John Wade and myself.
I wouldn't have thought to work out the probability (either as a frequentist or Bayesian) of being Rick rolled by the first footnote!! ๐