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The frontal eye fields (FEF) are a region located in the
frontal cortex The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove ...
, more specifically in
Brodmann area 8 Brodmann area 8 is one of Brodmann's cytologically defined regions of the brain. It is involved in planning complex movements. Human Brodmann area 8, or BA8, is part of the frontal cortex in the human brain. Situated just anterior to the prem ...
or BA8, of the primate
brain The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head ( cephalization), usually near organs for special ...
. In humans, it can be more accurately said to lie in a region around the intersection of the
middle frontal gyrus The middle frontal gyrus makes up about one-third of the frontal lobe of the human brain. (A ''gyrus'' is one of the prominent "bumps" or "ridges" on the surface of the human brain.) The middle frontal gyrus, like the inferior frontal gyrus ...
with the
precentral gyrus The precentral gyrus is a prominent gyrus on the surface of the posterior frontal lobe of the brain. It is the site of the primary motor cortex that in humans is cytoarchitecturally defined as Brodmann area 4. Structure The precentral gyrus li ...
, consisting of a frontal and parietal portion. The FEF is responsible for saccadic eye movements for the purpose of visual field perception and awareness, as well as for voluntary eye movement. The FEF communicates with extraocular muscles indirectly via the
paramedian pontine reticular formation The paramedian pontine reticular formation, also known as PPRF or paraabducens nucleus, is part of the pontine reticular formation, a brain region without clearly defined borders in the center of the pons. It is involved in the coordination of eye ...
. Destruction of the FEF causes deviation of the eyes to the ipsilateral side.


Function

The cortical area called frontal eye field (FEF) plays an important role in the control of visual attention and eye movements. Electrical stimulation in the FEF elicits saccadic eye movements. The FEF have a topographic structure and represents saccade targets in
retinotopic Retinotopy (from Greek τόπος, place) is the mapping of visual input from the retina to neurons, particularly those neurons within the visual stream. For clarity, 'retinotopy' can be replaced with 'retinal mapping', and 'retinotopic' with 'r ...
coordinates. The frontal eye field is reported to be activated during the initiation of
eye movements Eye movement includes the voluntary or involuntary movement of the eyes. Eye movements are used by a number of organisms (e.g. primates, rodents, flies, birds, fish, cats, crabs, octopus) to fixate, inspect and track visual objects of inte ...
, such as voluntary
saccade A saccade ( , French for ''jerk'') is a quick, simultaneous movement of both eyes between two or more phases of fixation in the same direction.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishin ...
s and pursuit eye movements. There is also evidence that it plays a role in purely sensory processing and that it belongs to a “fast brain” system through a
superior colliculus In neuroanatomy, the superior colliculus () is a structure lying on the roof of the mammalian midbrain. In non-mammalian vertebrates, the homologous structure is known as the optic tectum, or optic lobe. The adjective form '' tectal'' is commo ...
medial dorsal nucleus The medial dorsal nucleus (or dorsomedial nucleus of thalamus) is a large nucleus in the thalamus. It is believed to play a role in memory. Structure It relays inputs from the amygdala and olfactory cortex and projects to the prefrontal cortex a ...
– FEF ascending pathway. In humans, its earliest activations in regard to visual stimuli occur at 45 ms with activations related to changes in visual stimuli within 45–60 ms (these are comparable with response times in the
primary visual cortex The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and ...
). This fast brain pathway also provides auditory input at even shorter times starting at 24 ms and being affected by auditory characteristics at 30–60 ms. The FEF constitutes together with the
supplementary eye fields Supplementary eye field (SEF) is the name for the anatomical area of the dorsal medial frontal lobe of the primate cerebral cortex that is indirectly involved in the control of saccade, saccadic Eye movement (sensory), eye movements. Evidence for ...
(SEF), the
intraparietal sulcus The intraparietal sulcus (IPS) is located on the lateral surface of the parietal lobe, and consists of an oblique and a horizontal portion. The IPS contains a series of functionally distinct subregions that have been intensively investigated usin ...
(IPS) and the
superior colliculus In neuroanatomy, the superior colliculus () is a structure lying on the roof of the mammalian midbrain. In non-mammalian vertebrates, the homologous structure is known as the optic tectum, or optic lobe. The adjective form '' tectal'' is commo ...
(SC) one of the most important brain areas involved in the generation and control of eye movements, particularly in the direction contralateral to the frontal eye fields' location. In addition, FEF has an important role in the covert allocation of spatial attention through its reciprocal connectivity with visual cortex.


Clinical significance


Lesions

Unilateral irritative stimulation of a FEF causes conjugate gaze contralateral to the stimulation. Conversely, a unilateral destructive lesion of the FEF causes conjugate gaze towards the lesion.


See also

*
Saccade A saccade ( , French for ''jerk'') is a quick, simultaneous movement of both eyes between two or more phases of fixation in the same direction.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishin ...
*
Smooth pursuit In the scientific study of vision, smooth pursuit describes a type of eye movement in which the eyes remain fixated on a moving object. It is one of two ways that visual animals can voluntarily shift gaze, the other being saccadic eye movement ...
*
Supplementary eye fields Supplementary eye field (SEF) is the name for the anatomical area of the dorsal medial frontal lobe of the primate cerebral cortex that is indirectly involved in the control of saccade, saccadic Eye movement (sensory), eye movements. Evidence for ...
* IPS /
LIP The lips are the visible body part at the mouth of many animals, including humans. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech. Human lips are a tactile sensory organ, and can be ...


References


External links


Frontal Eye Field (Scholarpedia)
{{Visual system Saccade Brodmann areas Cerebral cortex Frontal lobe