Cellphone Use May Reveal Your 'Dominant Brain'
People with left-brain dominance tend to listen with right ear, and vice-versa, study finds
By Alan Mozes
FRIDAY, May 17 (HealthDay News) -- New research suggests the dominant side of your brain may make the call on which ear you choose to use while talking on your cellphone.
The dominant side of your brain is where your speech and language center resides. Ninety-five percent of the human population is left-brain dominant, and those people tend to be right-handed. The opposite holds true for people who are right-brain dominant. In this study, scientists found that roughly 70 percent of those surveyed held their cellphone up to the ear that was on the same side as their dominant hand.
This insight into the way people use their cellphones could one day help doctors quickly and safely locate and protect a patient's language center before beginning a potentially risky brain operation, the researchers said.
"In essence, this could be used as a poor man's Wada test," said study author Dr. Michael Seidman, director of the division of otologic/neurotologic surgery at the Henry Ford Health System in West Bloomfield, Mich. "[The Wada test] is the standard test used today to determine exactly where a surgical patient's language center is located, which is critical information to have if you want to carefully preserve a person's language abilities.
"The Wada test is, however, invasive and risky," Seidman said. "But by looking at how a person uses their cellphone, which side they listen in to, you can get shorthand insight into brain dominance. It's not a foolproof guarantee, but I would say it's a pretty reliable and safe way of going about it."
Seidman and his colleagues reported their findings in the May issue of the journal JAMA Otolaryngology -- Head & Neck Surgery.
To explore how brain dominance may relate to cellphone handling, the authors sifted through more than 700 online surveys completed by people who were members of a web-based otology (hearing) discussion group, as well as those already undergoing Wada and MRI testing for various purposes.
Respondents were asked to give information regarding their cellphone habits, favored hand for executing various tasks (such as writing, throwing and cellphone handling) and any hearing-loss issues. Any history of brain, head or neck tumors also was noted.
Ninety percent of those polled were right-handed, and 68 percent used their right ear, 25 percent used their left ear and 7 percent used both ears.
The story was similar among the left-handed people: 72 percent used their left ear, 23 percent used their right ear and 5 percent used both ears.
The team concluded that there is an association between cellphone handling habits and brain dominance, with right-ear cellphone use typically indicating left-brain dominance, and vice versa.
"We're pretty confident in our results," Seidman said. "Basically, if your speech and language centers are in the left side of the brain -- which for most people they are -- a cellphone conversation is going to sound better in your right ear."
"The next question is if this information may help us figure out whether or not cellphone use is associated with cancer risk," he said.
On that front, Seidman suggested that, if there was such an association, there would be a much greater incidence of right-sided brain, head and neck cancer than currently is the case, given that nearly 80 percent of all people use their right ear to talk on their phones.
"But the question of cancer risk and cellphone use is very controversial," he said. "We just don't know yet. Much more work needs to be done."
Dr. Joe Verghese, a professor of neurology at the Albert Einstein College of Medicine, in New York City, suggested that it remains possible that other variables could influence the way people choose to handle their cellphones.
"This is certainly a very interesting study," Verghese said. "But it could also be that right-handed people, for example, simply reach for their cellphone with their dominant hand, and then naturally feel more comfortable continuing to keep it and use it on their right side because it would feel awkward to pick up a phone with your right hand and then switch it over to your left side.
"If that's the case, this could actually be about motor dominance more than auditory or language dominance," he said.
For more on left- and right-brain dominance, visit the American Psychological Association.
SOURCES: Michael Seidman, M.D., director, division of otologic/neurotologic surgery, department of otolaryngology -- head and neck surgery, Henry Ford Health System, West Bloomfield, Mich.; Joe Verghese, M.D., professor, neurology, Albert Einstein College of Medicine, New York City; May 2013 JAMA Otolaryngology -- Head & Neck Surgery