Rather than focusing on the traditional mobile phone health risk – the possibility that long-term phone use could lead to brain cancer – the study of 300 people found that mobile phones cause a slowing of brain activity. However, the research, published in the International Journal of Neuroscience this month, reported that the slowed brain effects are still considered within normal brain functioning. A longer study with a larger sample group would consider whether the slowed brain activity should be considered an adverse health effect, according to a statement from Brainclinics Diagnostics, one of the groups involved in the study. The noted slowed brain function could not be explained by differences in personality, according to researchers. “In Alzheimer’s dementia you also find a severe slowing of brain activity,” said Martijn Arns, the main investigator for Brainclinics Diagnostics. “However, the slowing found in this study, with mobile phone users, can still be considered within ‘normal’ limits”. Still, Arns predicted that a longer-term study would show more severe effects. Of the 300 people in the study, only 100 were frequent mobile phone users; 100 were non-mobile phones users and the third group of 100 were an intermediate user group. Differences in brain activity, as measured with quantitative EEG (electroencephalographic) studies, and neuropsychological functions such as attention, memory, executive function and personality, were assessed. Among the results, frequent users scored higher on ratings as extraverts and were found to be less open-minded. The study also found that frequent users also showed improved focused attention, which was explained by a learning effect from making more phone calls in busy places where users would have to focus better on a phone call while filtering out background noise and other distractions. Despite this improved focus and the findings about personality, the frequent users showed more instances of slowed activity as measured by delta and theta EEG power, as well as a slowdown in a measurement called alpha peak frequency. The researchers cited several other studies going back to 1998 on the short-term effects of mobile phone use, some of which showed that frequent users improved their scores on cognitive tests. Those positive outcomes were linked to small increases in brain temperature, which led to faster metabolic activity and thus faster reaction times. However, the researchers in the current study claim that the previous studies were inconclusive. In the recent study, Brainclinics was joined by researchers at Radbound University in Nijmegen, the Institute of Psychiatry in London and The Brain Resource in Sydney.
