Wednesday, February 23, 2011

JAMA: Cell Phone Use Stimulates Brain Activity




# 5334



Concerns over the potential health ramifications of long-term & frequent cell phone use continues despite a number of studies that have yielded inconsistent results.


In May of 2010, the International Agency for Research on Cancer (IARC) released their long-delayed INTERPHONE report, which was unable to establish a link between cell phone use and brain tumors  (see The IARC Cell Phone Report)


Of course, it can sometimes take years – or even decades – of research before the full effect of a new technology like cellular communications can be adequately established.


Today we’ve a new study that looks at how cell phone radiation affects brain activity, which is published in the February 23rd issue of JAMA.


The short version is: Prolonged exposure to cell phone radiation has now been shown to increase brain activity, but the clinical significance (if any) of such increases are unknown.


First a link and some excerpts from the abstract, followed by links to a video, press release, after which I will return.



Effects of Cell Phone Radiofrequency Signal Exposure on Brain Glucose Metabolism

Nora D. Volkow, MD; Dardo Tomasi, PhD; Gene-Jack Wang, MD; Paul Vaska, PhD; Joanna S. Fowler, PhD; Frank Telang, MD; Dave Alexoff, BSE; Jean Logan, PhD; Christopher Wong, MS


Objective To evaluate if acute cell phone exposure affects brain glucose metabolism, a marker of brain activity

Conclusions In healthy participants and compared with no exposure, 50-minute cell phone exposure was associated with increased brain glucose metabolism in the region closest to the antenna. This finding is of unknown clinical significance.

The link to the press release, embargoed until yesterday afternoon, follows:


Cell Phone Use May Have Effect on Brain Activity, But Health Consequences Unknown


Media Advisory: To contact Nora D. Volkow, M.D., call the NIH press office at 301-496-5787 or email

To contact editorial co-author Lennart Hardell, M.D., Ph.D., email

Cell Phone Use May Have Effect on Brain Activity, But Health Consequences Unknown

CHICAGO – In a preliminary study, researchers found that 50-minute cell phone use was associated with increased brain glucose metabolism (a marker of brain activity) in the region closest to the phone antenna, but the finding is of unknown clinical significance, according to a study in the February 23 issue of JAMA.


“The dramatic worldwide increase in use of cellular telephones has prompted concerns regarding potential harmful effects of exposure to radiofrequency-modulated electromagnetic fields (RF-EMFs). Of particular concern has been the potential carcinogenic effects from the RF-EMF emissions of cell phones. However, epidemiologic studies of the association between cell phone use and prevalence of brain tumors have been inconsistent (some, but not all, studies showed increased risk), and the issue remains unresolved,” according to background information in the article. The authors add that studies performed in humans to investigate the effects of RF-EMF exposures from cell phones have yielded variable results, highlighting the need for studies to document whether RF-EMFs from cell phone use affects brain function in humans.


(Continue . . . )



This study basically used PET scans (Positron emission tomography) to chart the brain’s activity via it’s uptake of F-FDG, a radioactive pharmaceutical used for imaging the heart, lungs, and brain.


Participants underwent PET Scans with cell phones placed on their left and right ears; once with the right cell phone `on’ (with sound muted) for 50 minutes and once with both cell phones `off’.


Areas of the brain in close proximity to the antennas of the activated cell phones demonstrated increased glucose uptake, indicating increased localized brain activity in response to the RF (radio frequency) emissions.


This study indicates that the prolonged use of a cell phone does affect brain activity. What all this might mean in regards to human health is unknown for now.


In an accompanying editorial, Cell Phone Radiofrequency Radiation Exposure and Brain Glucose Metabolism, Henry Lai, PhD & Lennart Hardell, MD, PhD write:


“Although the biological significance, if any, of increased glucose metabolism from acute cell phone exposure is unknown, the results warrant further investigation. An important question is whether glucose metabolism in the brain would be chronically increased from regular use of a wireless phone with higher radiofrequency energy than those used in the current study. Potential acute and chronic health effects need to be clarified. Much has to be done to further investigate and understand these effects.”


These authors also question whether the changes to brain function detected in this study could adversely affect other physiological functions of the body.


Admittedly, not many answers from this study. 

But it raises a lot of questions.

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