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NeuraQuarium

Neural-net evolution in a chill aquatic environment · By urocyongames

(Seemingly) Unreadable Brains

A topic by FireTurkeyOne created Dec 12, 2022 Views: 699 Replies: 2
Viewing posts 1 to 3

The Bibites discord is still messing with Neura, but we haven't been able to crack the critters brains! Which, y'know, makes it a bit hard to take a deeper look into their behaviors and how they're governed.

Got anything to help us?

Developer(+3)

Well, there's nothing simple about Critter brains, but I'll try and at least give you some pointers to help you out!


Here's a brand new random Critter and its brain. Brains are read from top to bottom. You can hover your mouse over each neuron to get a readout on it. Here my mouse is on the upper left neuron, the Hunger Input. When reading a Critter brain, here's a color code:

Yellow: ACTIVE (Positive)
Purple: ACTIVE (Negative)
White: Neutral

Synapses come in three Types: Standard (White), Absolute (Blue) and Inverted (Red.) Synapses have their Type color at the start and their Activation color at their end. So you can see that first Hunger Input Neuron in the upper left is Active, and has a Standard Synapse going straight down that's also Active, and two Inverted Synapses that are Inactive. (I'll explain what these Synapses are about later.)

All Critters have the same Inputs and Outputs (though the Decay Rates and Activation Thresholds for these may differ.) You can mouse across them to get the breakdown but briefly, Critters have inputs for Hunger, Pain, Maturity, Temperature, and then various inputs for Scent and Vision. They have Outputs for Forward/Backward movement, Turning Left and Right, Releasing Musk, Biting, trying to Reproduce, and Adrenaline (Rage if Negative, Sprint if Positive.)

The Neurons themselves have a unique build. Each one has a Threshold and a Decay Rate. Every tick, in typical neural network fashion, all of a Neuron's inputs are added together and fed in as the new value for the Neuron, but the Neuron's previous state plus or minus its Decay Rate (whatever gets it closer to 0) is added to those inputs as well. In this way, hidden neurons can possibly serve as a rudimentary "memory" -- high decay rate Input gets you what's happening now, a low decay neuron lower down taking a synapse from that input may tell you "This was happening recently."

If a neuron's State exceeds its Threshold (positive OR negative) then it feeds that value into its Synapses. If it's a Standard Synapse, the Neuron State gets passed down to the connected Neuron (multiplied by the Synapse strength, of course.) Absolute Synapses pass the absolute value of the activating Neuron's state: 0.5 and -0.5 both become 0.5. Inverted Synapses are funky -- they activate if the Neuron is INACTIVE and are neutral if the Neuron is Active. (So you can have a neural connection that's equivalent to "I don't smell blood" or whatever.)

Hope that helps; feel free to ask if you have any questions!

Developer(+3)

To give you a little additional detail:

Most Inputs are only ever positive. The exceptions are the Sensory Angle Inputs for Vision and Scent, which give the angle from the Critter to the strongest Scent or "most significant" (as a function of size, proximity, and taking camouflage into account) nearby visual object. The Angle inputs are positive or negative according to which side of the Critter the sensation comes from.

Similarly, some outputs only really do something if they're Active with a positive value, but there are also exceptions. Left and Right rotation do nothing if negative, but the Forward/Back output neuron causes the Critter to swim forward if positive, backward if negative. The "Breed" output acts the same as long as it's active, regardless of positive or negative -- if the Critter has the energy, it will reproduce with a nearby compatible partner. If there's no nearby partner, it will check its energy levels again and reproduce asexually if it has the energy (Partnered breeding is half as expensive.) Finally the "Adrenaline" output works like this -- if the Critter is not "exhausted" (on cooldown) it will either puff its body up and go into a "Rage", temporarily boosting Strength, or stretch out its tail and "Sprint," boosting its Speed.