Role of the frontal eye field in human microsaccade responses: a TMS study

Previous studies using muscimol inactivations in the frontal eye fields (FEFs) have shown that saccades generated by recall from working memory are eliminated by these lesions, whereas visually guided saccades are relatively spared. In these experiments, we made reversible inactivations in FEFs in alert macaque monkeys and examined the effect on saccades in a choice response task. Our task required monkeys to learn arbitrary pairings between colored stimuli and saccade direction. Following inactivations, the percentage of choice errors increased as a function of the number of alternative (NA) pairings. In contrast, the percentage of dysmetric saccades (saccades that landed in the correct quadrant but were inaccurate) did not vary with NA. Saccade latency increased postlesion but did not increase with NA. We also made simultaneous inactivations in both FEFs. The results following bilateral lesions showed approximately twice as many choice errors. We conclude that the FEFs are involved in the generation of saccades in choice response tasks. The dramatic effect of NA on choice errors, but the lack of an effect of NA on motor errors or response latency, suggests that two types of processing are interrupted by FEF lesions. The first involves the formation of a saccadic intention vector from associate memory inputs, and the second, the execution of the saccade from the intention vector. An alternative interpretation of the first result is that a role of the FEFs may be to suppress incorrect responses. The doubling of choice errors following bilateral FEF lesions suggests that the effect of unilateral lesions is not caused by a general inhibition of the lesioned side by the intact side.

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The role of the frontal eye field in visual stability: optokinetic stimulation during TMS-EEG

10.26226/morressier.5b31ec5f2afeeb001345b93e ◽

2018 ◽

Author(s):

Angela Mastropasqua

Keyword(s):

Frontal Eye Field ◽

Optokinetic Stimulation ◽

Visual Stability ◽

Eye Field

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Vergence Eye Movements

The Neurology of Eye Movements ◽

10.1093/med/9780199969289.003.0009 ◽

2015 ◽

pp. 520-568 ◽

Cited By ~ 3

Author(s):

R. John Leigh ◽

David S. Zee

Keyword(s):

Eye Movements ◽

Developmental Disorders ◽

Laboratory Evaluation ◽

Frontal Eye Field ◽

Pontine Nuclei ◽

Convergence Insufficiency ◽

Eye Field ◽

Phoria Adaptation ◽

Visual Cortical

This chapter reviews the stimuli for vergence, the properties of fusional and accommodative vergence, as well as vergence made in combination with saccades or vestibular eye movements, or blinks. Different properties of horizontal, vertical, and torsional vergence are discussed. Current models are presented to account for interactions between vergence and saccades. The neural substrate for vergence movements is reviewed from ocular motoneurons to the midbrain supraoculomotor area, to visual cortical areas such as MST and frontal eye field, including pontine nuclei, cerebellar vermis, and fastigial nucleus. Adaptive properties of vergence are reviewed, especially phoria adaptation, discussing the role of the cerebellum. The bedside and laboratory evaluation of vergence is summarized and the pathophysiology of disorders of vergence discussed, including developmental disorders associated with childhood strabismus and acquired disorders such as convergence spasm, convergence insufficiency, vergence forms of nystagmus such as convergence-retraction nystagmus, and effects of focal pontine lesions.

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Suppression of smooth pursuit eye movements induced by electrical stimulation of the monkey frontal eye field

Journal of Neurophysiology ◽

10.1152/jn.00182.2011 ◽

2011 ◽

Vol 106 (5) ◽

pp. 2675-2687 ◽

Cited By ~ 5

Author(s):

Yoshiko Izawa ◽

Hisao Suzuki ◽

Yoshikazu Shinoda

Keyword(s):

Electrical Stimulation ◽

Smooth Pursuit ◽

Suppressive Effect ◽

Frontal Eye Field ◽

Pursuit Eye Movements ◽

Physiological Properties ◽

Eye Field ◽

Catch Up ◽

Stimulation Of

This study was performed to characterize the properties of the suppression of smooth pursuit eye movement induced by electrical stimulation of the frontal eye field (FEF) in trained monkeys. At the stimulation sites tested, we first determined the threshold for generating electrically evoked saccades (Esacs). We then examined the suppressive effects of stimulation on smooth pursuit at intensities that were below the threshold for eliciting Esacs. We observed that FEF stimulation induced a clear deceleration of pursuit at pursuit initiation and also during the maintenance of pursuit at subthreshold intensities. The suppression of pursuit occurred even in the absence of catch-up saccades during pursuit, indicating that suppression influenced pursuit per se. We mapped the FEF area that was associated with the suppressive effect of stimulation on pursuit. In a wide area in the FEF, suppressive effects were observed for ipsiversive, but not contraversive, pursuit. In contrast, we observed the bilateral suppression of both ipsiversive and contraversive pursuit in a localized area in the FEF. This area coincided with the area in which we have previously shown that stimulation suppressed the generation of saccades in bilateral directions and also where fixation neurons that discharged during fixation were concentrated. On the basis of these results, we compared the FEF suppression of pursuit with that of saccades with regard to several physiological properties and then discussed the role of the FEF in the suppression of both pursuit and saccades, and particularly in the maintenance of visual fixation.

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The role of the right frontal eye field in overt visual attention deployment as assessed by free visual exploration

Neuropsychologia ◽

10.1016/j.neuropsychologia.2015.01.027 ◽

2015 ◽

Vol 74 ◽

pp. 37-41 ◽

Cited By ~ 5

Author(s):

Dario Cazzoli ◽

Simon Jung ◽

Thomas Nyffeler ◽

Tobias Nef ◽

Pascal Wurtz ◽

...

Keyword(s):

Visual Attention ◽

Visual Exploration ◽

Frontal Eye Field ◽

Eye Field ◽

Attention Deployment ◽

The Right

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Role of expected reward in frontal eye field during natural scene search

Journal of Neurophysiology ◽

10.1152/jn.00119.2016 ◽

2016 ◽

Vol 116 (2) ◽

pp. 645-657 ◽

Cited By ~ 22

Author(s):

Joshua I. Glaser ◽

Daniel K. Wood ◽

Patrick N. Lawlor ◽

Pavan Ramkumar ◽

Konrad P. Kording ◽

...

Keyword(s):

Eye Movements ◽

Neural Activity ◽

Search Task ◽

Behavioral Changes ◽

Frontal Eye Field ◽

Natural Scene ◽

Firing Rates ◽

Eye Field ◽

Movement Representation

When a saccade is expected to result in a reward, both neural activity in oculomotor areas and the saccade itself (e.g., its vigor and latency) are altered (compared with when no reward is expected). As such, it is unclear whether the correlations of neural activity with reward indicate a representation of reward beyond a movement representation; the modulated neural activity may simply represent the differences in motor output due to expected reward. Here, to distinguish between these possibilities, we trained monkeys to perform a natural scene search task while we recorded from the frontal eye field (FEF). Indeed, when reward was expected (i.e., saccades to the target), FEF neurons showed enhanced responses. Moreover, when monkeys accidentally made eye movements to the target, firing rates were lower than when they purposively moved to the target. Thus, neurons were modulated by expected reward rather than simply the presence of the target. We then fit a model that simultaneously included components related to expected reward and saccade parameters. While expected reward led to shorter latency and higher velocity saccades, these behavioral changes could not fully explain the increased FEF firing rates. Thus, FEF neurons appear to encode motivational factors such as reward expectation, above and beyond the kinematic and behavioral consequences of imminent reward.

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Transcranial Magnetic Stimulation of the Human Frontal Eye Field: Effects on Visual Perception and Attention

Journal of Cognitive Neuroscience ◽

10.1162/089892902320474553 ◽

2002 ◽

Vol 14 (7) ◽

pp. 1109-1120 ◽

Cited By ~ 140

Author(s):

Marie-Hélène Grosbras ◽

Tomáš Paus

Keyword(s):

Eye Movements ◽

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Right Hemisphere ◽

Visual Detection ◽

Frontal Eye Field ◽

Target Onset ◽

Eye Field ◽

The Right

When looking at one object, human subjects can shift their attention to another object in their visual field without moving the eyes. Such shifts of attention activate the same brain regions as those involved in the execution of eye movements. Here we investigate the role of one of the main cortical oculomotor area, namely, the frontal eye field (FEF), in shifts of attention. We used transcranial magnetic stimulation (TMS), a technique known to disrupt transiently eye-movements preparation. We hypothesized that if the FEF is a necessary element in the network involved in shifting attention without moving the eyes, then TMS should also disrupt visuospatial attention. For each volunteer, we positioned the TMS coil over the probabilistic anatomical location of the FEF, and we verified that single pulses delayed eye movements. We then applied TMS during a visuospatial attention task. In this task, a central arrow directed shifts of attention and the subject responded by a keypress to a subsequent visual peripheral target without moving the eyes from the central fixation point. In a few trials, the cue was invalid or uninformative, yielding slower responses than when the cue was valid. We delivered single pulses either 53 msec before or 70 msec after target onset. Contrary to our prediction, the main effect of the stimulation was a decrease in reaction time when it was applied 53 msec before target onset. TMS over the left hemisphere facilitated responses to targets in the right hemifield only and for all cueing conditions, whereas TMS over the right hemisphere had a bilateral effect for valid and neutral but not invalid cueing. Thus, TMS interfered with shift of attention only in the case of right hemisphere stimulation: it increased the cost of invalid cueing. Our results suggest that TMS over the FEF facilitates visual detection, and thereby reduces reaction time. This finding provides new insights into the role of the human FEF in processing visual information. The functional asymmetry observed for both facilitation of visual detection and interference with shifts of attention provides further evidence for the dominance of the right hemisphere for those processes. Our results also underline that the disruptive or facilitative effect of TMS over a given region depends upon the behavioral context.

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