Link found between number of Facebook friends and brain size

Scientists have discovered a link between the number of friends a Facebook user has and the size of certain regions in their brain.

The discovery suggests that the use of social networking sites might actually change our brains. The specific brain regions in question play a role in memory, emotional responses and social interactions.

Researchers at University College London (UCL) used magnetic resonance imaging (MRI) to study the brains of 125 university students who were all active Facebook users. They then cross-checked the results against another group of 40 students.

They found a strong connection between the number of Facebook friends and the quantity of grey matter in the amygdala, the right superior temporal sulcus, the left middle temporal gyrus and the right entorhinal cortex. Grey matter is the layer of brain tissue where mental processing happens.

The thickness levels of grey matter in the amygdala were also linked to the amount of real-world friends people had, but the size of the other three regions appeared to be connected only to the amount of online friends that people had.

The students, on average, had around 300 Facebook friends, with the most connected having up to 1,000.

Ryota Kanai of University College London (UCL) said: “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.”

The study was published in the journal Proceedings of the Royal Society.