Cell phone use stimulates brain activity


Former Executive Editor, Harvard Health

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We all know that using a cell phone can stimulate the brain to work a bit harder. “Mr. Skerrett? This is Dr. LeWine’s office. Do you have a minute to talk about your test results?” or “Dad, a bunch of kids are going to Casey’s house after the dance. Can I go?” But a new study published in JAMA is making me wonder what the energy emitted by the phone itself, not just the information it delivers, is doing to my brain.

Here’s the study in a nutshell. Dr. Nora Volkow and her colleagues recruited 47 volunteers to have their brain activity measured twice by a PET scanner. Both times the volunteer had a cell phone strapped to each ear. During one measurement, both phones were turned off. During the other, one phone was turned on but muted so the volunteer didn’t know it was on; the other was left off.  Each session lasted about an hour. The scans showed a small increase in the brain’s use of glucose (blood sugar) when the phone was on, but only in parts of the brain close to the antenna.

It was an elegant study. The researchers took pains to anticipate sources of error. They used a control (both phones off) against which to compare the effect of a “live” cell phone. They used cell phones on each ear, one on and one off, to see if the effect was localized. They muted the phone that was on to eliminate the possibility that any brain activation was due to listening to the sound of a voice coming through the phone’s speaker. So the result is probably a real one, not an artifact or measurement error.

What does this brain activation mean? No one really knows. As Dr. Volkow told NPR, “I cannot say if it is bad that they [cell phones] are increasing glucose metabolism, or if it could be good.”

The big worry, of course, is brain cancer, not brain activation. It’s a controversial and hotly debated topic. But with conflicting evidence linking cell phone use with brain cancer, this study will probably push the debate in both directions. Some will see the results as reassuring—the brain activation during the 50 minutes the one cell phone was on was less than that seen when you open your eyes or listen to music. Others will see the brain activation as a possible early step toward cancer.

I’m with Dr. Volkow and others who think that this study means it’s worth taking a closer look at how the energy radiated by a cell phone, a mobile phone, or any other energy-emitting device we hold next to our heads affects the brain. I’m also going to avoid 50-minute conversations by cell phone (the duration in the study) and save those for when I’m using a head set or my old-fashioned, noncordless land line.


  1. Gerard Butler Workout

    Thank you, thats very interesting information. I need to share with my friends.
    Gerard Butler Workout

  2. John

    I suggest you to avoid talking to the phone! It is bad 🙁 Better use some other kind of communication methods, such as Skype.

    Get a laptop and start chatting and using the communication over the internet.

  3. Rami

    Thank you for sharing this information ! But aren’t cellphores dangerous for brain ?
    Rami Pira

  4. briandudes123@gmail.com

    Thanks for good information about cellphones.

  5. wawan

    The information you provide is very useful to me as Cellular Phone user. I hope that was released later will reduce the serious impact on the human brain.

  6. Anonymous

    Good enough reason to switch to communicating with mobile tablets. With our society becoming more mobile everyday, the use of digital products will become more prevalent as technology continues to push the envelope of communication. Eventually, we may be able to eliminate thge use of cell phones altogether.

  7. Some genuinely great info , Sword lily I discovered this. “Nothing can resist the human will that will stake even its existence on its stated purpose.” by Benjamin Disraeli.

  8. Mike

    Holy cow. More than enough reason to use headsets in using cellphone. If cellphone stimulates our brain during the use of cellphone, I have to agree that it will lead to cancer in the future. Good thing to know about this stuff.


  9. Rob

    It’s scary to think these little devices we have in our pockets or held up to our heads will one day cause disease or cancer.

    I wonder if some cell phone cases can block some of the EM radiation?

  10. Mike

    I personally believe in the future you will see a huge spike in brain cancer. Some scientists are convinced radiation will eventually get the better of a user over their lifespan. On a side note, with these new gadgets and cell phones being so expensive,there are alot of good alternative computers and ipads.

  11. Anonymous

    Use of cellphones is increasing continuously in a rapid manner and the adverse effects associates are well-known as well. There are several thermal effects associated and many non-thermal effects as well like cancer, hypersensitivity, Genotoxic effects, and blood-brain barrier effects as well. There are a lot of solutions available for these problems and must be used to keep the health in a good position.
    [URL removed by moderator]

  12. Laptop Repair Man

    We all now use mobile phones without any though of whether they are causing any effects on our brains. Hopefully, no effects occur at all, but I am sure that it is more likely that some of the cells are altered in some way. This may, however, have no impact on the individual so is considered harmless.

  13. iphone 5

    Thanks for the great information. Really a great article. thank you!

  14. Dave

    I’ve heard this some years ago but I’m not really sure that it’s really damaging your brain. I’m afraid it’s just the same as some Fake Medical Theories
    probably it’s because of the mobile frequency?
    however, if this is really true, will using earphone / headset help preventing this?


  15. Ayu "Ting Ting"

    Well this is a welcomed article being as I was just reading about the risks of cancer from using cell phones, bluetooth,etc The thought of being able to simulate my brain while talking on the phone is very welcomed information I have to read more on this


  16. Filipp

    Better dont use a phone very often, like many womans like to do. Such as my wife, she can talk more than 4 hours dayly. I am personaly talks maybe 10 mins per day. This is good.

  17. David Hastings

    Better take some precautions tho. Although tests are inconclusive, keep your phone conversations sweet and short.

  18. Latrice

    I remember a time when there was a big concern over having cellphones so close to ones head. It was thought that it could cause cancer or other health threatening things. Now, we learn that this certainly not the case and that it may actually help our brain activity. Thanks for the article. It definitely gives us more to think about.


  19. Mark Gregory

    I always thought that cellphone emit radiation that is harmful. And the radiation contribute to cancer. That’s why I prefer to use earphone whenever possible.


  20. Fred

    A lot has been said in light of various research’s about mobile phone usage and the damage it cause. Still, the number of cell phone users are increasing every year at a real fast rate. What does this all means?

    People are more concerned about gadgets and entertainment, like the new iPhone, and they hardly care about serious health issues, as cancer.

    There must be an awareness program which will teach people about the dangers of using a cell phone, and that might help them.

  21. David

    I have been researching the effects mobile phones has on the brain. Its interesting to see that Iphone 4 is one of the worst. I hope Apple make the Iphone 5 less damaging.

  22. Juan

    The use of any electronic equipment that generates electromagnetic waves have an effect on the surrounding objects. If the brain is basically a huge electrical circuit, mediated by electrical impulses, there is no reason to think that it affects you.
    Therefore it is important to have comprehensive information and purchase cell phones that emit low radiation, just in case.
    [URL removed by moderator]

  23. Anita

    An anonymous post below says that Bluetooths appear not to cause the changes in brain activity that cell phones held to the ear do. I keep reading that but wonder if there’s a study out there as authoritative as the one reported on here that addresses the Bluetooth issue?

  24. Rami

    i;m almost sure the use of cellphones does have some influance on our brain,it’s enough to feel the heat around where cellphones touch our head to know there some reaction going on therelet’s hope it’s not a harmful one,this kind of studies can help a lot in understaning how to <a relieve headaches

  25. manuel

    this information about Cell phone use stimulates brain activity
    is very interest, because thousands of people use in all world.
    is necessary to find an solution.!!!
    soon the smartphone replace the PC (desk and laptop).
    if use chat, email, facebook, twitter, myspace. (social networks), abrir procesadores de texto, hojas de calculo, adobe pdf.
    no longer need to buy a PC!!!

    cellular phone companies
    need to remove the risks and provide better products
    [URL removed by moderator]

  26. Anonymous

    A great way to avoid the issue is to use a bluetooth headset. They have been shown not to stimulate the brain like cell phones do.

  27. Graylin Sanders

    Well this is a welcomed article being as I was just reading about the risks of cancer from using cell phones, bluetooth,etc The thought of being able to simulate my brain while talking on the phone is very welcomed information I have to read more on this

  28. John

    Interesting study, however, for me, the affect on our brain is still causes worries. Great post, thanks for sharing.

    [URL removed by moderator]

  29. lhalay

    I wake-up early in the morning to read every article.thanks to the liable informations.

  30. Kaye Swain

    Thanks for a very interesting article. I often write at SandwichINK on the topics of how practical cell phones for senior citizens can be for those of us dealing with the issues of caring for elderly parents. It’s rather intriguing to think there might actually be some positive health benefits as well (as opposed to all the negative warnings we usually hear).

  31. Pedro

    Thanks for this information. I have been searching for this for a few time now.
    Keep up the good work!

    Pedro Sousa
    [URL removed by moderator]

  32. Mike

    I saw this bit on abc news. I have been doing some research for an expository essay that i am writing. My concern isn’t so much the cell phones of today but the cell phones of the future. It seems to be trend that as each year passes we have more powerful cell phones that are coming out to us all the time. The cell phone that you can get today is more powerful than my first Compaq computer ever was! So as the power increases on these cell phones will it affect our brains more and more? I guess we will have to wait for that study.

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