Editing Automatic gain control (section)

=== Biological===

As is the case with many concepts found in engineering, automatic gain control is also found in biological systems, especially sensory systems.  For example, in the [[vertebrate]] [[visual system]], calcium dynamics in the [[retina]]l [[photoreceptor cell|photoreceptor]]s adjust gain to suit light levels.  Further on in the visual system, cells in V1 are thought to mutually inhibit, causing normalization of responses to contrast, a form of automatic gain control.  Similarly, in the [[auditory system]], the [[Olivocochlear system#Effects of electrical stimulation|olivocochlear efferent]] neurons are part of a biomechanical gain control loop.<ref>{{cite book
 | chapter = Functional roles of the inner-and outer-hair-cell subsystems in the cochlea and brainstem
 | title = Hearing science: Recent advances
 | editor = C. I. Berlin
 | author = D. O. Kim
 | publisher = College Hill Press
 | year = 1984
 | pages = 241–262
 | url = http://kimdolab.uchc.edu/Kim-84.PDF
 | access-date = 2010-10-13
 | archive-url = https://web.archive.org/web/20100701024647/http://kimdolab.uchc.edu/Kim-84.PDF
 | archive-date = 2010-07-01
 | url-status = dead
 }}</ref><ref>{{cite book
 | chapter = Automatic Gain Control in Cochlear Mechanics
 | title = The Mechanics and Biophysics of Hearing
 | editor = P. Dallos
 | author = R. F. Lyon
 | publisher = Springer-Verlag
 | year = 1990
 | pages = 395–402
 | url = http://www.dicklyon.com/tech/AGC_MOH1990.pdf
 | display-editors = etal
 }}{{Dead link|date=October 2019 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>