Monkeys might not be known for their generosity, but when they do seem to act selflessly, a specific area in their brains keeps track of these kindnesses.

The discovery of this neuronal tally chart may help scientists to understand the neural mechanisms underlying normal social behaviour in primates and humans, and might even provide insight into disorders such as autism, in which social processing is disrupted.

Steve Chang and his colleagues from Duke University in Durham, North Carolina, used electrodes to directly record neuronal activity in three areas of the brain prefrontal cortex that are known to be involved in social decision-making, while monkeys performed reward-related tasks.

Read more at Nature.