Snails' brains shut down until they found food, researcherslearned

Scientists have discovered that snails solve complex decisions
using just two brain cells, in a discovery that could help engineers
develop energy efficient robots.
By attaching electrodes to the brain circuitry of freshwater snails
that were on the hunt for food, researchers learned the molluscs
used only two neurons when they found a tasty lettuce.

Scientists discovered that snails used controller and motivator
neurons to feed back information to each other to decide whether
or not to eat.

The first brain cell let it know it had discovered food and the
second cell decided whether it was hungry.
But if no food was in front of the snail this part of its brain
circuitry shut down, saving energy.
University of Sussex Professor George Kemenes, who led the
research, said "What goes on in our brains when we make
complex behavioural decisions and carry them out is poorly
understood.
"Our study reveals for the first time how just two neurons can
create a mechanism in an animal's brain which drives and
optimises complex decision-making tasks.
"It also shows how this system helps to manage how much
energy they use once they have made a decision.
"Our findings can help scientists to identify other core neuronal
systems which underlie similar decision-making processes.
"This will eventually help us design the 'brains' of robots based on
the principle of using the fewest possible components necessary
to perform complex tasks."