False ‘missing toe’ sensation(s) [digital agnosia]

Do you ever get an uncanny feeling that one of your toes is missing, despite the fact that they’re all there? You’re not alone.

“To the best of our knowledge, the present study is the first to document the [erroneous] experience of a ‘missing toe’ in healthy volunteers.”

Toes-missing“Nineteen young adult participants underwent tactile stimulation of the digits [toes] with the eyes closed and verbally reported the identity of the stimulated digit. In the majority of individuals, responses to the second and third toes were significantly biased toward the laterally neighboring digit. The directional bias was greater for the nondominant foot and was affected by the identity of the immediately preceding stimulated toe. Unexpectedly, 9/19 participants reported the subjective experience of a ‘missing toe’ or ‘missing space’ during the protocol.”

Note: “9/19” in this context is taken to mean nine-out-of-ninteen, or, if you prefer, nine-nineteenths (rather than nine-divided-by nineteen) that’s to say, roughly equivalent to 47%.

See: Tactile Toe Agnosia and Percept of a ‘‘Missing Toe’’ in Healthy Humans  in: Perception, 2016, Vol. 45(3) 265–280. Authors: Nela Cicmil (Department of Physiology, Anatomy & Genetics, University of Oxford,UK and The Medical School, University of Oxford, John Radcliffe Hospital, UK). Achim P. Meyer (Bernstein Center for Computational Neuroscience, Humboldt University, Berlin, Germany) and John F. Stein (Department of Physiology, Anatomy & Genetics, University of Oxford, UK). in: Perception, 2016, Vol. 45(3) 265–280