Why Some People Can't Tell Right from Left

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Some people confuse easily when asked to distinguish left from right and vice versa, and it’s not a terribly uncommon occurrence.

Gerard Gormley, a senior academic general practitioner at Queen’s University Belfast, writes in The Conversation about this problem that he says affects “a significant portion of our population.” It may not seem like rocket science to some of us, but Gormley says that left-right confusion is a “complex neuro-psychological process involving several higher neurological functions such as the ability to integrate sensory and visual information, language function, and memory.”

When someone (most likely your GPS) is giving you directions, do you pause when they say, “Turn right here”? Taking a wrong turn is hardly life-threatening; for most people the issue causes no more than some embarrassment or inconvenience. But what if you were in a profession where it was your livelihood to know the difference?

Gormley writes:

“Some of the most tragic errors in medicine have been when surgery was performed on the wrong side of a patient: removing the wrong kidney or amputating the wrong leg.”

Consider the hospital environment for a moment — it’s a distracting place to work, making the moment of distinguishing right from left all the more difficult for those who struggle.

Gormley has published research exploring “the impact of such interruptions on medical students’ ability to correctly discriminate right from left. While objectively measuring 234 medical students’ ability to distinguish right from left, we subjected them to the typical ambient noise of a ward environment and interrupted them with clinical questions.”

He writes that even the mere background noise of a hospital ward was enough to throw off the medical student’s ability to make a distinction between right and left. Asking them questions while trying to determine right from left “had an even greater impact.” Gormley notes that these distractions had the greatest effects on students who were older and female.

What’s more, some people may not realize they have a problem making left-right judgments. Try out this handy test to see if you might be deluding yourself.

Also, don’t try suggesting the “make an ‘L’ with your hand” trick. Gormley writes that research shows this technique has failed to assist people who struggle with this issue.