The biggest study to date into the effect of mobile phones on our brains has confirmed that certain ‘brainwaves’ do react to the devices. The research was recently completed by Professor Croft, Director of Swinburne’s Australian Centre for Radio Frequency Bioeffects Research, and his next step is to investigate how different age groups react to the technology.

To examine how the brain is affected by a mobile, Prof Croft carried out experiments on one hundred and ten people. In his study, he provides evidence that mobile phones cause a change in brain function that’s related to a particular frequency of brain activity, called alpha activity. “People have been waiting to see if it was possible to demonstrate there was something there,” he says. “This research is a good indication.”

This sample size of 110 people is much greater than previous studies, and supports findings from a study in 2005. “Alpha reports in the past have not used good methodology,” says Prof Croft. “But there was one carried out in 2005 which suggested there might be an effect. Our study was a replication of that using a much more substantial sample size. It’s the first good test of those 2005 findings.”

But as far as our health is concerned, Prof Croft says it’s still too early to tell whether mobiles are bad for us and whether this alpha change is having a positive or negative effect. “It’s difficult to determine whether or not this is a cause for concern,” he says. “This alpha change is not something you can look and say it means this or means that. It’s very sensitive and just about anything will change it and what we’re looking at is a tiny little affect. This study can’t answer the question of harm, but it’s a starting point to finding out.”

With this research completed, Professor Croft’s next step is to investigate whether a mobile reacts with different age groups in different ways. He’ll look at the 13 to 15 year old age group, and the 55 to 75 age group.

“It was interesting to demonstrate the alpha affect, as now we have something to work with,” says Prof Croft. “But what is particularly important is to extend this beyond the healthy young university students that we tend to use for these studies, and look at the real world. Although there’s a tiny effect on healthy young adults, there is a possibility that it could be much stronger in children or the elderly.”

Scientists have also not yet been able to conclusively determine what exactly is causing the brain to react, so Professor Croft is investigating that too. “It seems from other studies that results showing a change only come from studies that use a phone with a 217 hertz pulse signal. So we’re doing a large study with Professor Cosic from RMIT to separate the 217 hertz signal from the radio frequency.”

The research team is testing a group of seventy five people to see how they react to phones with 2 and 8 hertz pulses, a 217 hertz pulse, and very high radio frequency signals separately. “From there,” says Prof Croft, “we’ll be able to determine whether any particular component of a phone has an effect.”

Professor Croft’s study has been published in the Bioelectromagnetics Journal.