How complex environments push brain evolution
A recent study by neuroscientists offers clues about how increasingly difficult tasks have evolved the brain. They created a video game similar to the old video game Tetris, in which programmed artificial adaptive agents (“animats”) have to “catch” moving blocks of different sizes before the blocks reach the bottom.
To play the game, the animats have been endowed with a rudimentary neural system made up of eight nodes: two sensors, two motors, and four internal computers that coordinate sensation, movement and memory.
The computers ran code that makes up the animats’ “DNA”, it determines the wiring between the parts of the “brain” and also allows for random mutations, some of which made the animats better block-catchers.
The neuroscientists, at the University of Wisconsin-Madison and Michigan State University, watched as the animats played a video game in which they tried to “catch” falling blocks, learning to detect where they would land.
Then the scientists selected the best players of each generation and allowed them to replicate. (If that sounds familiar, you may have experimented with self-evolving cellular-automata gliders and spaceships in John Conway’s addictive “Game of Life.”)
Some animats played simpler versions of the game, but other animats played more and more complex versions over and over. At the end of 60,000 generations, they all had evolved more complex wiring in their neural networks, but the animats that did well in more complex versions of the game had developed particularly intricate neural networks.