Pinwheel
Pinwheels ( German Windrädchen ) are a structure in the functional architecture of the primary visual cortex (visual cortex) of mammals .
Many nerve cells in the visual cortex have a preferred stimulus orientation, so that they are most strongly activated by visual contours of a certain orientation relative to the horizontal axis of the visual field . In the visual cortex there are neurons for all possible stimulus orientations. In the vicinity of the so-called pinwheels, neurons for each stimulus orientation are arranged around a common center, the pinwheel center, like the spokes of a wheel.
The occurrence of pinwheels was predicted in 1982 by Nicholas Swindale , a neuroscientist from the University of British Columbia , from mathematical models for learning to see, and in 1987 it was experimentally demonstrated in complex derivation of electrical signals in the visual system. In 1991, Tobias Bonhoeffer and Amiram Grinvald at Rockefeller University in New York succeeded for the first time in making this structure directly visible using high-resolution optical methods.
Individual evidence
- ^ Translation on dict.leo.org
- ^ NV Swindale: A model for the formation of orientation columns. In: Proc R Soc Lond B Biol Sci. 215 (1199), May 22, 1982, pp. 211-230.
- ^ NV Swindale et al: Surface organization of orientation and direction selectivity in cat area 18. In: J Neurosci. 7 (5), May 1987, pp. 1414-1427.
- ↑ T. Bonhoeffer, A. Grinvald: Iso-orientation domains in cat visual cortex are arranged in pinwheel-like patterns. In: Nature. 353 (6343), Oct 3, 1991, pp. 429-431.