Cell phone use reveals dominant hand–ear link
medwireNews: Which ear a person chooses to use when talking on a cell phone may give a clue as to which side of their brain is dominant for language and auditory processes, US scientists report.
"Our findings have several implications, especially for mapping the language center of the brain," said Michael Seidman (Henry Ford Health System, Detroit, Michigan) in a press release.
"By establishing a correlation between cerebral dominance and sidedness of cell phone use, it may be possible to develop a less-invasive, lower-cost option to establish the side of the brain where speech and language occurs rather than the Wada test, a procedure that injects an anesthetic into the carotid artery to put part of the brain to sleep in order to map activity."
Overall, 717 participants - including otology patients, patients undergoing Wada testing and imaging, and university members - completed the authors' online survey.
Ninety percent of the respondents were right-handed, based on a modified version of the Edinburgh Handedness Inventory, and 68% of these participants used their right ear while on a cell phone, 26% their left ear, and 6% either ear. Of the 9% of respondents who were left-handed, 73% used their left ear, 23% their right ear, and 4% had no preference.
Interestingly, of the 1% of participants who were ambidextrous all expressed a preference with 50% using their left and 50% their right ear.
Among participants with self-reported comparable hearing in their ears, the researchers found that 85% and 79% of right- and left-handed respondents, respectively, used the ear on the same side as their dominant hand.
For respondents with better hearing in their right ear, the corresponding values were 75% and 50%, while in those with better hearing in their left ear, 30% and 67% of right- and left-handed participants used the same ear as their dominant hand.
"Controlling for ambidextrous users, bilateral cell phone users, and users with hearing disorders, most right-handed people preferred to use their cell phone on their right ear, and most left-handed people preferred to use their cell phone on their left ear," Siedman et al write in JAMA Otolaryngology.
But they note that some respondents reported using their non-preferred ear for cell phone conversations to free their dominant hand for multitasking.
The team adds that their research may also shed light on the purported relationship between cell phone use and the risk for brain, head and neck cancer: "It would be interesting to determine if the incidence of any particular type of tumor has shown an increasing predilection to the right side over the past 20 years (since cell phones have been popularized), as this would suggest a possible association."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Lynda Williams, Senior medwireNews Reporter