Study links Facebook friends with brain regions

A study by UCL researchers suggests that the size of certain brain regions in an individual may be linked to their number of Facebook friends. The researchers found a strong correlation between the number of friends and the amount of grey matter in regions including the amygdala, the right superior temporal sulcus, left middle temporal gyrus and the right entorhinal cortex. The three latter regions were not, however, correlated to real-world friend networks.

These regions of the brain are associated with memory processing, emotional responses and perception, notably in identifying objects as biological. A previous study suggested that the volume of grey matter in the amygdala is larger in people with greater real-world friend networks. This study suggests the same is true when referring to online friends.

Professor Geraint Rees, a Wellcome Trust Senior Clinical Research Fellow at UCL, looked at MRI scans of the brains of 125 university students who actively used Facebook and performed the study taking into account the size of their real-world and online friend networks. A strong link was found between the number of Facebook friends an individual had and the amount of grey matter in the aforementioned parts of their brain. The findings were replicated in a group of another 40 students and were later published in the journal Proceedings of the Royal Society B.

The researchers emphasise that this does not represent a causal link and it is not possible to determine from the study whether maintaining more Facebook friends results in greater volumes of grey matter or individuals that have larger brain regions are hard-wired to have more friends. Professor Rees said that “online social networks are massively influential, yet we understand very little about the impact they have on our brains”. Dr Ryota Kanai, the first author of the study added “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”.

Facebook is the world’s most popular social networking site with over 800 million global active users. The study also looked at how many real-world friends an individual had compared to their Facebook friends, and showed a positive correlation in that respect. It involved asking participants questions such as “how many friends are in your phonebook?”, “how many people would you invite to a party?”, “how many friends have you kept from school and university?” and “how many friends do you have on Facebook?”, allowing for an estimation of social network sizes.

The findings support the idea that “most Facebook users use the site to support their existing social relationships, maintaining or reinforcing these friendships, rather than just creating networks of entirely new, virtual friends”, Professor Rees added. Students on average had around 300 Facebook friends, ranging from 150 to 1,000.

Dr Heidi Johansen-Berg from the University of Oxford noted the findings were intriguing but emphasised that adding a large amount of Facebook friends would not constitute a short cut to making people brainier. She added the critique that “the number of Facebook friends you have [may be] more strongly related to how much time you spend on the internet, how old you are, or what mobile phone you have”, concluding that “the study cannot tell us whether using the internet is good or bad for our brains”.

The Wellcome Trust Centre for Neuroimaging seeks to understand the brain in greater detail, with scientists studying higher cognitive function in order to identify how thought and perception arise from brain activity. Dr John Williams, head of Neuroscience and Mental Health at the Wellcome Trust said “we cannot escape the ubiquity of the internet and its impact on our lives, yet we understand little of its impact on the brain, which we know is plastic and can change over time”.