Image caption It is hoped the research may help engineers design more efficient "robot brains"

Snails use two brain cells to make "complex decisions", a team of scientists has found.

Researchers at the University of Sussex said one cell told the snail if it was hungry while the other cell told it if food was present.

The experiments used electrodes to measure brain activity of the molluscs when searching for lettuce.

Lead researcher Prof George Kemenes said the discovery would help engineers design "robot brains".

He said these would be based on the principle of using the fewest possible components necessary to perform complex tasks.

"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," he said.

"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."

The study was published in the journal Nature Communications .