Decision to Give a Group Effort in the Brain

Dec. 23, 2012 — A monkey would probably never agree that it is better to give than to receive, but they do apparently get some reward from giving to another monkey.

During a task in which rhesus macaques had control over whether they or another monkey would receive a squirt of fruit juice, three distinct areas of the brain were found to be involved in weighing benefits to oneself against benefits to the other, according to new research by Duke University researchers.

The team used sensitive electrodes to detect the activity of individual neurons as the animals weighed different scenarios, such as whether to reward themselves, the other monkey or nobody at all. Three areas of the brain were seen to weigh the problem differently depending on the social context of the reward. The research appears Dec. 24 in the journal Nature Neuroscience.

Using a computer screen to allocate juice rewards, the monkeys preferred to reward themselves first and foremost. But they also chose to reward the other monkey when it was either that or nothing for either of them. They also were more likely to give the reward to a monkey they knew over one they didn't, preferred to give to lower status than higher status monkeys, and had almost no interest in giving the juice to an inanimate object.

Continued:  http://www.sciencedaily.com/releases/2012/12/121223152732.htm