Dorsal Prefrontal Cortex

2021 ◽  
pp. 191-235
Author(s):  
Richard E. Passingham
Keyword(s):  
Prefrontal Cortex ◽  
Eye Movements ◽  
Frontal Eye Field ◽  
Intraparietal Sulcus ◽  
Order Information ◽  
Shape Information ◽  
Eye Field ◽  
Orbital Prefrontal Cortex ◽  
Ventral Prefrontal Cortex ◽  
Premotor Areas

The dorsal prefrontal (PF) cortex generates and plans the goals or targets for foveal search and manual foraging. The goals are conditional on the relative recency of prior events and actions, and the connections of areas 9/46 and 46 explain how these areas can support the ability to generate the next goal. Area 9/46 can generate sequences of eye movements because it has visuospatial inputs from the cortex in the intraparietal sulcus and outputs to the frontal eye field and superior colliculus. Area 46 can generate sequences of hand and arm movements because it has inputs from the inferior parietal areas PFG and SII and outputs to the forelimb regions of the premotor areas and thence to the motor cortex. Both areas get timing and order information indirectly from the parietal cortex and hippocampus, and colour and shape information from the ventral prefrontal cortex. Inputs from the orbital prefrontal cortex enable both areas to integrate generate goals in accordance with current needs.

Ventral Prefrontal Cortex

2021 ◽  
pp. 236-284
Author(s):  
Richard E. Passingham
Keyword(s):  
Prefrontal Cortex ◽  
Temporal Cortex ◽  
Inferior Temporal Cortex ◽  
Long Term Memory ◽  
Frontal Eye Field ◽  
Visual Inputs ◽  
Superior Temporal Cortex ◽  
Eye Field ◽  
Ventral Prefrontal Cortex

The ventral prefrontal cortex learns to associate objects, faces, and vocalizations, and its connectional fingerprint explains why it alone can do so. It receives visual inputs from the inferior temporal cortex and auditory ones from the superior temporal cortex. It combines these inputs with those from the orbital prefrontal (PF) cortex so as to specify the goal that is currently desirable. This is then transformed into the target of search via connections with the frontal eye field and the target for manual retrieval via connections with the premotor areas. The ventral PF cortex can also learn to form associations between objects, for example by linking them into categories. These can be retrieved from long-term memory via connections with the hippocampus.

scholarly journals Disparity Sensitivity of Frontal Eye Field Neurons

2000 ◽  
Vol 83 (1) ◽  
pp. 625-629 ◽  
Author(s):  
Stefano Ferraina ◽  
Martin Paré ◽  
Robert H. Wurtz
Keyword(s):  
Eye Movements ◽  
Dimensional Space ◽  
Visual Stimuli ◽  
Three Dimensional ◽  
Frontal Eye Field ◽  
Visual Responses ◽  
Motor Processes ◽  
Uncrossed Disparity ◽  
Eye Field ◽  
Three Dimensional Space

Information about depth is necessary to generate saccades to visual stimuli located in three-dimensional space. To determine whether monkey frontal eye field (FEF) neurons play a role in the visuo-motor processes underlying this behavior, we studied their visual responses to stimuli at different disparities. Disparity sensitivity was tested from 3° of crossed disparity (near) to 3° degrees of uncrossed disparity (far). The responses of about two thirds of FEF visual and visuo-movement neurons were sensitive to disparity and showed a broad tuning in depth for near or far disparities. Early phasic and late tonic visual responses often displayed different disparity sensitivity. These findings provide evidence of depth-related signals in FEF and suggest a role for FEF in the control of disconjugate as well as conjugate eye movements.

scholarly journals TMS over the Human Frontal Eye Field Distorts Perceptual Stability across Eye Movements

2010 ◽  
Vol 10 (7) ◽  
pp. 518-518
Author(s):  
F. Ostendorf ◽  
J. Kilias ◽  
C. Ploner
Keyword(s):  
Eye Movements ◽  
Frontal Eye Field ◽  
Perceptual Stability ◽  
Eye Field

Saccadic Dyskinesia, Other Involuntary Eye Movements, and Gaze Deviations

2008 ◽  
Author(s):  
Agnes Wong
Keyword(s):  
Multiple Sclerosis ◽  
Eye Movements ◽  
Normal Subjects ◽  
Mesencephalic Reticular Formation ◽  
Frontal Eye Field ◽  
Square Wave ◽  
Central Mesencephalic Reticular Formation ◽  
Cerebellar Diseases ◽  
Eye Field ◽  
Small Saccade

■ A small saccade of 0.5–3° that takes the eye away from fixation, followed by a saccade that returns the eye back to fixation after about 200 msec (i.e., presence of intersaccadic interval during which visual feedback occurs) ■ So named because of its appearance in eye movement tracings ■ Normal subjects often have square wave jerks (SWJ), but the rate is only 4–6 per minute. ■ Pathologic SWJ occurs at a rate of >15 per minute. ■ Cerebellar diseases Square wave jerks result from damage of projections from the frontal eye field, rostral pole of the superior colliculus, and the central mesencephalic reticular formation to the omnipause cells in the pons. If symptomatic, SWJ may be treated with methylphenidate, diazepam, phenobarbital, or amphetamines. ■ Burst of saccades with defective steps of innervation (i.e., stepless saccades) ■ Conjugate or monocular Saccadic pulses are associated with multiple sclerosis. Saccadic pulses result from damage of omnipause cells or the neural integrator.

scholarly journals Electrical Stimulation of the Frontal Eye Field in a Monkey Produces Combined Eye and Head Movements

2000 ◽  
Vol 84 (2) ◽  
pp. 1103-1106 ◽  
Author(s):  
Tyson A. Tu ◽  
E. Gregory Keating
Keyword(s):  
Electrical Stimulation ◽  
Eye Movements ◽  
Head Movements ◽  
Frontal Eye Field ◽  
Gaze Shifts ◽  
Gaze Shift ◽  
Eye Field ◽  
A Site ◽  
Head Rotations ◽  
Stimulation Of

The frontal eye field (FEF), an area in the primate frontal lobe, has long been considered important for the production of eye movements. Past studies have evoked saccade-like movements from the FEF using electrical stimulation in animals that were not allowed to move their heads. Using electrical stimulation in two monkeys that were free to move their heads, we have found that the FEF produces gaze shifts that are composed of both eye and head movements. Repeated stimulation at a site evoked gaze shifts of roughly constant amplitude. However, that gaze shift could be accomplished with varied amounts of head and eye movements, depending on their (head and eye) respective starting positions. This evidence suggests that the FEF controls visually orienting movements using both eye and head rotations rather than just shifting the eyes as previously thought.

The effect of frontal eye field and superior colliculus lesions on saccadic latencies in the rhesus monkey

1987 ◽  
Vol 57 (4) ◽  
pp. 1033-1049 ◽  
Author(s):  
P. H. Schiller ◽  
J. H. Sandell ◽  
J. H. Maunsell
Keyword(s):  
Eye Movements ◽  
Superior Colliculus ◽  
Short Latency ◽  
The Other ◽  
Frontal Eye Field ◽  
Express Saccades ◽  
Unimodal Distribution ◽  
Other Hand ◽  
Eye Field ◽  
The Mean

Rhesus monkeys were trained to make saccadic eye movements to visual targets using detection and discrimination paradigms in which they were required to make a saccade either to a solitary stimulus (detection) or to that same stimulus when it appeared simultaneously with several other stimuli (discrimination). The detection paradigm yielded a bimodal distribution of saccadic latencies with the faster mode peaking around 100 ms (express saccades); the introduction of a pause between the termination of the fixation spot and the onset of the target (gap) increased the frequency of express saccades. The discrimination paradigm, on the other hand, yielded only a unimodal distribution of latencies even when a gap was introduced, and there was no evidence for short-latency "express" saccades. In three monkeys either the frontal eye field or the superior colliculus was ablated unilaterally. Frontal eye field ablation had no discernible long-term effects on the distribution of saccadic latencies in either the detection or discrimination tasks. After unilateral collicular ablation, on the other hand, express saccades obtained in the detection paradigm were eliminated for eye movements contralateral to the lesion, leaving only a unimodal distribution of latencies. This deficit persisted throughout testing, which in one monkey continued for 9 mo. Express saccades were not observed again for saccades contralateral to the lesion, and the mean latency of the contralateral saccades was longer than the mean latency of the second peak for the ipsiversive saccades. The latency distribution of saccades ipsiversive to the collicular lesion was unaffected except for a few days after surgery, during which time an increase in the proportion of express saccades was evident. Saccades obtained with the discrimination paradigm yielded a small but reliable increase in saccadic latencies following collicular lesions, without altering the shape of the distribution. Unilateral muscimol injections into the superior colliculus produced results similar to those obtained immediately after collicular lesions: saccades contralateral to the injection site were strongly inhibited and showed increased saccadic latencies. This was accompanied by a decrease of ipsilateral saccadic latencies and an increase in the number of saccades falling into the express range. The results suggest that the superior colliculus is essential for the generation of short-latency (express) saccades and that the frontal eye fields do not play a significant role in shaping the distribution of saccadic latencies in the paradigms used in this study.(ABSTRACT TRUNCATED AT 400 WORDS)

Sign in / Sign up

Export Citation Format

Share Document