The game challenges players to grow their neuron as long as possible; climbing through brain tissue, out-competing rival neurons and creating as many connections to distant regions of the brain as they can.
This involves clicking on nodes in an effort to climb higher and higher. A speedy mouse finger is essential as a rapidly shrinking sphere marks the areas that are accessible and once no unclaimed nodes are within it, it's gameover. Brain freeze. Play it here and read more (silly) below and (clever) here.
I like to think of it as the process my mind goes through when writing a post; the green boost nodes that automatically build connections are the equivalent of discovering the perfect pun. The purple nodes that expand the zone of influence are a delicious cup of coffee. Once a game is complete, links point outward to articles about parts of the brain. It's sobering to know that I just built a pontine mossy fibre projecting neuron and sure beats simply having 10 million points.
Axon is from Preloaded and it's not the first time they've gone all science on us. Remember the Futurecade stuff? That was they as well.