Four neurons and two connections are enough to make a brain that loves light
Simple circuits can create complex behaviors
Aatish Bhatia's interactive essay builds a tiny virtual creature called a spark and gives it a brain of just four neurons. Wiring one eye to one flipper produces a creature that charges at light like a comet; crossing the connections makes it flee; swapping excitatory links for inhibitory ones makes it glide toward the light and stop, as if drawn by a magnet. Small wiring changes yield four distinct behaviors, suggesting that behavior emerges from neural circuits rather than magic.
If you saw creatures behaving like this in the wild, you might attribute some rudimentary intelligence to them. But we've just shown you how this apparent intelligence arises from the bottom up, with just four neurons and two connections. There's no magic here.
- Animats
The ancestor is not Braitenberg. It's Grey Walter's turtles.
In 1948, W. Grey Walter built two simple robots that could sense light and touch.[1] Much complex behavior emerged. That's where this idea started.
Watch the video.[2] It's very impressive for 1948 and tube technology.
If you've seen an original Roomba, you've seen a similar level of intelligence. Rod Brooks went down this road. But it didn't go very far. There are severe limits to purely reactive robotics. It doesn't work well for anything that moves fast enough that inertia matters.
- tancop
> If you saw creatures behaving like this in the wild, you might attribute some rudimentary intelligence to them.
> But we’ve just shown you how this apparent intelligence arises from the bottom up, with just four neurons and two connections. There’s no magic here. In this view, behavior emerges from neural circuits.
Isn't the conclusion here that very simple behaviors like the sparks are intelligent? I would say even a single neuron has some tiny amount of intelligence, and what the author means by "no magic" and "emergent behavior" is just a different perspective that minimizes it.
- georgestrakhov
Check out Valentino Braitenberg's vehicles. It's one of my favourite books ever.
- TehCorwiz
Growing up I tinkered with BEAM robotics. It's a philosophy of design that begins with these types of very simple reactive circuits usually from scavenged parts. It's nice to see someone break down the effect of different variables in the design.
- bob1029