A hypercomplex cell (currently called an end-stopped cell) is a type of visual processing neuron in the mammalian cerebral cortex. Initially discovered by David Hubel and Torsten Wiesel in 1965, hypercomplex cells are defined by the property of end-stopping, which is a decrease in firing strength with increasingly larger stimuli. The sensitivity to stimulus length is accompanied by selectivity for the specific orientation, motion, and direction of stimuli. For example, a hypercomplex cell may only respond to a line at 45˚ that travels upward. Elongating the line would result in a proportionately weaker response. Ultimately, hypercomplex cells can provide a means for the brain to visually perceive corners and curves in the environment by identifying the ends of a given stimulus .[1]
Hypercomplex cells were originally characterized as the superordinate class of visual processing cells above complex and simple cells. Whereas complex cells were sensitive to moving stimuli of specific orientations that travel in a specific direction, simple cells only responded to properly oriented linear stimuli. Neither simple nor complex cells were believed to display end-stopping. Likewise, end-stopping was believed to be restricted to higher order visual areas (Brodmann area 18 and Brodmann area 19), but was later discovered to also exist in the primary visual cortex (Brodmann area 17). By 1968, Geoffrey Henry and Bogdan Dreher discovered simple and complex cells with end-stopping properties. Subsequently, hypercomplex cells were no longer recognized as a distinct class but rather a subtype of simple and complex cells. Currently, simple end-stopped and complex end-stopped cells are the terms of choice to describe neurons with end-stopping properties.[1]
Brodmann area 17 (red) and higher order visual areas, Brodmann area 18 (orange) and Brodmann area 19 (yellow), are part of the visual cortex.
^ abHubel, D.H., & Wiesel, T.N. (2005). Brain and visual perception: the story of a 25-year collaboration. New York, New York: Oxford University Press.
A hypercomplexcell (currently called an end-stopped cell) is a type of visual processing neuron in the mammalian cerebral cortex. Initially discovered...
fields of cells in the visual cortex into simple cells, complex cells, and hypercomplexcells. Simple cell receptive fields are elongated, for example with...
tesseract and the 16-cell is a regular octagon. The octonions are a hypercomplex normed division algebra that are an extension of the complex numbers...
JSTOR 3605147. S2CID 125356690. Kantor, I. L.; Solodownikow, A. S. (1989). Hypercomplex Numbers: An Elementary Introduction to Algebras. Translated by Shenitzer...
the Quaternion Society, devoted to the study of quaternions and other hypercomplex number systems. From the mid-1880s, quaternions began to be displaced...
mathematical and scientific notation linearly using standard six-dot Braille cells for tactile reading by the visually impaired. The code was developed by...
symmetric, involutive, linear operation on 2m real numbers (or complex, or hypercomplex numbers, although the Hadamard matrices themselves are purely real)....
quaternion difference p – q also produces a segment equipollent to pq. Other hypercomplex number systems also used the idea of a linear space with a basis. Arthur...
earthquake prediction, molecular biology and inquiries into the nature of living cells themselves. Control theory is an interdisciplinary branch of engineering...
"the cold, wet, rain-wet streets of Göttingen" after class discussing hypercomplex number systems and their representations. Von Neumann's habilitation...
scientist, statistician and business executive Irene Sabadini, Italian hypercomplex analyst Flora Sadler (1912–2000), Scottish mathematician and astronomer...
and led to a subsequent analytical theory; they also began the use of hypercomplex numbers. Karl Weierstrass and others carried out the arithmetization...
Global Information