Here's a neural network concept from the 90s where the neurons are bathed in diffusing neuromodulator 'gases', inspired by nitric oxide action in the brain. It'

Here's a neural network concept from the 90s where the neurons are bathed in diffusing neuromodulator 'gases', inspired by nitric oxide action in the brain. It's a source of slow semi-local dynamics for the network meta-parameter optimization (GA) to make use of. You could change these networks' behavior by tweaking the neuromodulators! https://sussex.figshare.com/articles/journal_contribution/Better_Living_Through_Chemistry_Evolving_GasNets_for_Robot_Control/23338559 https://sussex.figshare.com/articles/journal_contribution/Be... I'm not an author. I followed the work at the time.