A new study found that the hand you hold your cell phone to your ear with is determined by brain region dominance.
Researchers found that left-brain thinkers use their right hand, while right-brain thinkers use their left.
The left-side of the brain is said to be used for logical reasoning, whereas the right-side is used more often for creativity.
The study looked at more than 717 survey respondents with 90 percent of people being right-handed, nine percent left and one percent ambidextrous.
That said, only 68 percent of people hold their phone to their right ear, 25 percent used the left and seven percent used both.
Ninety five percent of people tend to be left-brain dominant.
The idea of the study was to be able to quickly find which side of the brain has the dominant language center.
So most people who hold the phone on their right-side will be left-brain dominant and their speech and language center will also reside there.
"We're pretty confident in our results," said the study authors.
"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 cell phone trick only works if hearing is equally good in both ears.
The study was published in JAMA Otolarynology-Head & Neck Surgery.