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The time it takes to elicit a visual cortical response plus the time to elicit a saccade from cortex (FEF) is longer than the time it takes for humans to orient towards faces.

Nakano et al. take this as further evidence for a sub-cortical (retinotectal) route of face detection.

LIP and the FEF are usually connected to decision making.

FEF stimulation elicits saccadic eye movements.

Presaccadic activity is not measured in FEF for spontaneous saccades but for purposive saccades.

The motor map is not monotonic across the entire FEF, but sites that are close to each other have similar characteristic saccades.

Some cells in FEF respond to auditory stimuli.

Stimulating cells in FEF whose activity is elevated before a saccade of a given direction and amplitude usually generates a saccade of that direction and amplitude.

Onset times of visually guided saccades have a bimodal distribution. The faster type of saccades are termed `express saccades'. Ablation of the SC but not of the FEF makes express saccades disappear.

FEF ablation leads to a temporary visual neglect. This neglect disappears almost completely after a short time.

Removing both SCs and both FEFs leads to permanent deficits:

  • a decrease in fixation accuracy,
  • a neglect of the peripheral visual field,
  • saccade frequency is decreased,
  • the range of saccadic eye movements is reduced.

Schiller et al. did not observe the visuospatial neglect and stark loss of oculomotor function as did Sprague and Meikle.

Visually active neurons in FEF do not project to SC. Motion-related neurons in FEF project to SC.

There are ascending pathways from SC to the eye fields through talamic structures.

There is a disynaptic connection from SC to the dorsal stream visual cortex, probably through the pulvinar.

FEF and LIP stimulation elicits saccadic eye and head movements.

Lesions to SC and FEF individually do not eliminate saccades. Lesions to both do eliminate saccades.

Frontal eye fields (FEF) and intraparietal sulcus (IPS) have been associated with voluntary orienting of visual attention.

Activation of FEF and SC neurons is higher before direction error saccades in anti-saccade tasks than before correct anti-saccades.

Munoz and Everling assume that there are distinct populations of fixation and saccade neurons in the SC and FEF.

In a more recent paper, Casteau and Vitu state that there is some debate about that. However, they, too argue for distinct fixation neurons. On the other hand, they also state that fixation neurons probably are not located in the SC itself, which is in contrast of what Munoz and Everling write.

Lateral prefrontal cortex (LPFC) and frontal eye fields (FEF) are frontal cortex regions involved in visual attention and target selection.

In the pop-out condition of a visual search task, Buschman and Miller found that neurons in the posterior parietal cortex region LIP found the search target earlier than neurons in frontal cortex regions FEF and LPFC.

In the pure visual search condition of a visual search task, Buschman and Miller found that neurons in frontal cortex regions FEF and LPFC found the search target earlier than neurons in the posterior parietal cortex region LIP.

the frontal eye fields (fef) project to the SC and to the brainstem directly.