Smooth pursuit eye movements and saccadic eye movements in patients with delusional disorder

AbstractA region of dorsomedial frontal cortex (DMFC) has been implicated in planning and executing saccadic eye movements; hence it has been referred to as a supplementary eye field (SEF). Recently, activity related to executing smooth-pursuit eye movements has been recorded from the DMFC, and microstimulation here has been shown to evoke smooth eye movements. This report documents neuronal activity present in smooth-pursuit tasks where the predictability of target motion was manipulated. The activity of many neurons in the DMFC reached a peak when a predictable change in target motion occurred. Furthermore, the peak activity of some cells was systematically shifted by manipulating the duration of the target event, indicating that the network these neurons were in could learn the temporal characteristics of new target motion. Finally, the activity of most neurons tested was greater when target motion was predictable than when it was unpredictable. The results suggest that the DMFC participates in planning smooth-pursuit eye movements based on past stimulus history.

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Extraretinal Inputs to Neurons in the Rostral Superior Colliculus of the Monkey During Smooth-Pursuit Eye Movements

Journal of Neurophysiology ◽

10.1152/jn.2001.86.5.2629 ◽

2001 ◽

Vol 86 (5) ◽

pp. 2629-2633 ◽

Cited By ~ 21

Author(s):

Richard J. Krauzlis

Keyword(s):

Eye Movements ◽

Superior Colliculus ◽

Smooth Pursuit ◽

Saccadic Eye Movements ◽

Visual Response ◽

Smooth Pursuit Eye Movements ◽

Related Activity ◽

Pursuit Eye Movements ◽

Deep Layers ◽

Almost All

The intermediate and deep layers of the monkey superior colliculus (SC) are known to be important for the generation of saccadic eye movements. Recent studies have also provided evidence that the rostral SC might be involved in the control of pursuit eye movements. However, because rostral SC neurons respond to visual stimuli used to guide pursuit, it is also possible that the pursuit-related activity is simply a visual response. To test this possibility, we recorded the activity of neurons in the rostral SC as monkeys smoothly pursued a target that was briefly extinguished. We found that almost all rostral SC neurons in our sample maintained their pursuit-related activity during a brief visual blink, which was similar to the maintained activity they also exhibited during blinks imposed during fixation. These results indicate that discharge of rostral SC neurons during pursuit is not simply a visual response, but includes extraretinal signals.

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Pursuit Subregion of the Frontal Eye Field Projects to the Caudate Nucleus in Monkeys

Journal of Neurophysiology ◽

10.1152/jn.00501.2002 ◽

2003 ◽

Vol 89 (5) ◽

pp. 2678-2684 ◽

Cited By ~ 43

Author(s):

Dong-Mei Cui ◽

Yi-Jun Yan ◽

James C. Lynch

Keyword(s):

Eye Movements ◽

Basal Ganglia ◽

Caudate Nucleus ◽

Smooth Pursuit ◽

Saccadic Eye Movements ◽

Frontal Eye Field ◽

Smooth Pursuit Eye Movements ◽

Axon Terminals ◽

Pursuit Eye Movements ◽

Eye Field

It has been well established by recording, inactivation, and neuroanatomical studies that the caudate nucleus is important for the control of saccadic eye movements. However, until now, there has been little evidence that the caudate nucleus plays a role in smooth pursuit eye movements. In the present study, we physiologically identified the smooth pursuit subregion of the frontal eye field (FEFsem) and the saccadic subregion of the frontal eye field (FEFsac) in four Cebus monkeys. Anterogradely transported tracers (biotinylated dextran amines and wheat germ aglutinin conjugated to horseradish peroxidase) were then used to determine the efferent connections of the FEFsem to the caudate nucleus and to compare those connections with projections arising in the FEFsac. We observed dense projections from the FEFsem to the head and body of the caudate. The FEFsem and FEFsac terminal fields were of approximately equal density and total area. The region of FEFsem-labeled axon terminals overlapped only slightly with the region of FEFsac-labeled terminals. These results suggest that the caudate nucleus may play an important role in the control of smooth pursuit eye movements via feedback loops involving the basal ganglia and thalamus. Our results further suggest that the basal ganglia circuitry concerned with controlling visual pursuit is physically segregated from that concerned with controlling saccadic eye movements.

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