With Eyes Shut, We Can't Tell Our Toes Apart

This little piggy went to market—or was it that little piggy? According to researchers at Oxford University, it may be hard for people to tell which toe is which if their eyes are closed and someone's touching their lower digits—a condition called agnosia, AFP reports. In a study in the journal Perception, scientists had a group of 19 healthy (i.e., no brain damage or other malady that would affect sensation interpretation) volunteers between the ages of 22 and 34 stick out their feet and have their toes prodded, and while 94% knew if it was their big toe or little toe being touched, only 57%, 60%, and 79% could correctly ID their second, third, and fourth toes, respectively. Meanwhile, when asked to ID their fingers using the same method, the rate shot up to 99%. The most problems came in differentiating between the second and third toes, per a press release, and no subject was able to guess every toe correctly.

The confusion seemed to be more prevalent when testing a subject's non-dominant foot, and surprisingly, just under half of the volunteers reported feeling like one of their toes wasn't even there. "We do know of medical conditions that can cause people to lose the sense of one of their digits," Nela Cicmil, one of the study's co-authors, says in the release. "The people being tested here were healthy, yet some were reporting the feeling of a missing toe." Why this finding could potentially be useful: If healthy people aren't able to "feel" their toes accurately, tests that check toes for sensation or movement may not be the best method to assess if a patient may have brain damage. Plus, "a better understanding of the brain mechanisms that underlie simpler mistakes of body representation … will help us to understand disturbance of body image in more complex cases like anorexia," Cicmil tells AFP. (Read about another intriguing study, this one involving an omega-3 twist.)