Interesting approach to implement the jam's theme. I like the idea of playing brains and solving different platformer puzzle. I see what you did there.
However, in my opinion the brains feel a bit too heavy and the colliders of the spines are a little too big on the sides. Initially, i thought i can push against a platform while jumping and if i fell down the spikes wouldn't hit me.
Despite that, i like the game tho.