Microsaccade 2664501 223057086 2008-07-02T11:14:22Z Eug 511638 rm extra {{Otheruses}} {{Otheruses|Eye movement (disambiguation)}} '''Microsaccades''' are a kind of [[fixational eye movement]]. They are small, jerk-like, involuntary [[eye movements]], similar to miniature versions of voluntary [[saccade]]s. They typically occur during prolonged visual [[fixation (visual)|fixation]] (of at least several seconds), not only in humans, but also in other animals, especially those with [[fovea]]l vision ([[primate]]s, [[cat]]s, etc.). Microsaccade amplitudes vary from 2 to 120 [[arcminute]]s. The role of microsaccades in [[visual perception]] has been a highly debated topic which is still largely unresolved. It has been proposed that microsaccades correct displacements in eye position produced by drifts, although non-corrective microsaccades also occur. Microsaccades were also believed to prevent the [[retina]]l image from fading, but they do not occur often enough for that purpose, considering that perfectly [[stabilize]]d images can disappear from perception in a few seconds or less. The current consensus is that all fixational eye movements are important for the maintenance of visibility. Experiments in [[neurophysiology]] from different laboratories showed that fixational eye movements, particularly microsaccades, strongly modulate the activity of [[neurons]] in the visual areas of the [[macaque]] [[brain]]. In the [[lateral geniculate nucleus]] (LGN) and the [[primary visual cortex]] (V1), microsaccades can move a stationary stimulus in and out of a [[neuron]]'s [[receptive field]], thereby producing transient neural responses. Microsaccades might account for much of the response variability of neurons in visual area V1 of the awake monkey. Current research in visual [[neuroscience]] and [[psychophysics]] is investigating how microsaccades relate to fixation correction, control of binocular [[fixation disparity]] and [[attention]]al shifts. == See also == * [[Rapid eye movement sleep]] * [[Saccade]] ==References== === Notes === {{reflist|colwidth=40em}} === Bibliography === {{refbegin}} * R. H. S. Carpenter. ''Movements of the Eyes'' (Pion, London, 1988). * Susana Martinez-Conde, Stephen L. Macknik & David H. Hubel. The role of fixational eye movements in visual perception. ''Nature Reviews Neuroscience'' 5(3):229-240 (2004). [http://dx.doi.org/10.1038/nrn1348 doi:10.1038/nrn1348] {{refend}} [[Category:Eye]] [[de:Mikrosakkade]]