Hyperacuity

Ewald Hering's model, published 1899, of how a Vernier acuity stimulus is coded by a receptor array. Receptors marked c signal a different position code along the horizontal direction from either the position a code or the position b code.[1]

The sharpness of our senses is defined by the finest detail we can discriminate. Visual acuity is measured by the smallest letters that can be distinguished on a chart and is governed by the anatomical spacing of the mosaic of sensory elements on the retina. Yet spatial distinctions can be made on a finer scale still: misalignment of borders can be detected with a precision up to 10 times better than visual acuity, as already shown by Ewald Hering in 1899.[1] This hyperacuity, transcending by far the size limits set by the retinal 'pixels', depends on sophisticated information processing in the brain.

  1. ^ a b Strasburger, Hans; Huber, Jörg; Rose, David (2018). "Ewald Hering (1899) On the Limits of Visual Acuity: A Translation and Commentary. With a Supplement on Alfred Volkmann (1863) Physiological Investigations in the Field of Optics". i-Perception. 9 (3): 204166951876367. doi:10.1177/2041669518763675. PMC 5990881. PMID 29899967.