Is new technology altering the structure of our brains?

Chris - This whole idea that by plugging ourselves into the internet 24/7, wondering around with Twitter open on a mobile phone, so we're always continuously being bombarded with information, and also children, instead of going and having talk and chalk in the classroom are now being plugged in from an increasingly young age. My own daughter, at the age of 4, knows how to use YouTube. I mean, I guess that's what you're getting at - is there an impact on our health and on our brain health. Let's ask Hannah. Hannah, what do you think?

Hannah - Okay. Well there've been no causal studies done in either direction so far. So the question you're asking, is technology leading to change in the brain, so not the other way around.

For example, are certain types of brain predisposed to use or take advantage of new technology? So there's been no causal studies but there have been several correlational studies. And a correlation does not imply causation. So, Professor Geraint Rees from University College London published a study on the 19th of October in the journal, Proceedings of the Royal Society B on how the structure of focal parts of the brain are correlated with the size of our online social networks, specifically Facebook friends.

Chris - So the more friends you've got, he's asking, is there a relationship with the size of certain bits of your brain?

Hannah - Exactly and he found that people with a higher number of Facebook friends had a higher amount of gray matter, the brain tissue where the processing is done, in several regions of the brain, and one of these regions was the amygdala, an almond shaped structure that's associated with processing memory and emotional responses and there were size changes in other regions that related to perceiving moving objects and also, linked to memory and navigation so navigating, for example, through online social networks.

Chris - But again this comes back to the point that Kris made which is that, how do we know this is cause or effect? I mean, you started yourself saying, this may be association, not causal. So how does the Geraint Rees study there show that these people have these brain changes because they use these technologies, not just because they already have those changes and that makes them more likely to use the technology?

Hannah - Well, exactly. And the researchers are keen to stress that they found a correlation and not a cause. So in other words, it's not possible to say from the data whether having more Facebook friends makes the regions of the brain larger, or whether some people are hard wired to have more friends. So that at the moment is unclear, whether new technology leads to changes in the brain rather than vice versa. So there's lots of scientific debate about that at the moment and we're trying to get hold of hard robust data.

Chris; - Hannah, thank you very much. A bit like the taxi driver study which showed that taxi drivers in London who have the knowledge had a bigger hippocampus compared with non-taxi drivers but then again, we don't know if it's cause or effect.