A quick update while I’m thinking about – next time I sit down with the code I want to add a section to emulate the functionality of dopamine cells like those found within the ventral tegmental, and other neuromodulators. This is actually a major enhancement and something to give careful thought to before proceeding. At first I intended TFNN matrices to operate without global or semiglobalized synaptic modulation – IE the tfnn matrix would operate purely on the “mechanical nature” of electro-chemical reactions in axodendritic, axosomatic, and axoaxonic connections – no globalized chemical reactions within the system.
The more I study though, the more I realize how important dopamine and other neuromodulators are in the prefrontal cortex regions. Via message controlled signals, these modulators can facilitate GABA reactions, and hence temporarily “quiet” certain systems, allowing for concentration. I have a feeling that without dopamine emulation matrices would fall prey to a ubiquitous ADD of sorts, and perhaps fail to mold meaningful neural configurations in deeper matrices due to an overload of traffic on neural bridges coming from sensory thalami and cortices.
At first when I was kicking it around I was thinking of just modifying axoaxonic connection code to introduce a negative change to synaptic weights and have that emulate dopamine secretion. This isn’t accurate though, as dopamine is a modulator, not a permanent change to the synaptic weights.
I think this may call for another variable to be introduced into the neuron, one that keeps track of current affecting modulators. More space – but I also realize I have an unused integer currently in the neuron that I used during debug sessions, I’ll remap that for dopamine / other modulator use. I may use it or another variable in connection to track glutamate supply to emulate habituation effects as well. It will add very little additional calculation time.
It’s amazing how large the TFNN neuron has grown in complexity from when I first completed the code until now.
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