Why some people can’t tell left from right

Kelly Oakes in BBC Magazine:

When British brain surgeon Henry Marsh sat down beside his patient’s bed following surgery, the bad news he was about to deliver stemmed from his own mistake. The man had a trapped nerve in his arm that required an operation – but after making a midline incision in his neck, Marsh had drilled out the nerve on the wrong side of his spinal column.

Preventable medical mistakes frequently involve wrong-sided surgery: an injection to the wrong eye, for example, or a biopsy from the wrong breast. These “never events” – serious and largely preventable patient safety accidents – highlight that, while most of us learn as children how to tell left from right, not everyone gets it right. While for some people, telling left from right is as easy as telling up from down, a significant minority – around one in six people, according to a recent study – struggle with the distinction. Even for those who believe they have no issues, distractions such as ambient noise, or having to answer unrelated questions, can get in the way of making the right choice.

More here.