Mind and Body

Study: Number of Facebook Friends Linked With Brain Size



Scientists have found a direct link between the number of Facebook friends a person has and the size of particular brain regions. In addition, they found that the more Facebook friends a person has, the more real-world friends that person is likely to have.

However, the researchers said it is not possible from the data to say whether having more Facebook friends makes the regions of the brain larger or whether some people are ‘hard-wired’ to have more friends.

"Online social networks are massively influential, yet we understand very little about the impact they have on our brains,” said Professor Geraint Rees, a Wellcome Trust Senior Clinical Research Fellow at University College London. “This has led to a lot of unsupported speculation the Internet is somehow bad for us.”

For the study, Rees and his colleagues at the UCL Institute of Cognitive Neuroscience and the Wellcome Trust Center for Neuroimaging studied brain scans of 125 university students – all active Facebook users. They compared the scans against the size of the students’ friend networks, both online and in real life.

The researchers found a strong connection between the number of Facebook friends a person had and the amount of gray matter in several regions of the brain. One region was the amygdala, which is associated with processing memory and emotional responses. 

The volume of gray matter in this area is larger in people with a larger network of real world friends – and it appears the same is true for people with a larger network of online friends.

The size of three other regions – the right superior temporal sulcus, the left middle temporal gyrus and the right entorhinal cortex – also correlated with online social networks, but did not appear to correlate with real-world networks.

We have found some interesting brain regions that seem to link to the number of friends we have – both 'real' and 'virtual',” said Dr. Ryota Kanai, first author of the study. “The exciting question now is whether these structures change over time – this will help us answer the question of whether the Internet is changing our brains."