Some cognitive effects of frontal-lobe lesions in man

The study of patients undergoing unilateral frontal-lobe excisions for the relief of focal epilepsy has revealed specific cognitive disorders that appear against a background of normal functioning on many intellectual, perceptual and memory tasks. Lesions that invade the frontal eye field cause subtle impairments of voluntary oculomotor control, which reveal themselves as an inability to suppress an initial glance at a potentially distracting stimulus. After frontal lobectomy in either hemisphere, deficits are found quite consistently on motor-differentiation tasks (Konorski 1972) in which the subject must learn to produce different responses to different, randomly presented, environmental signals. More directly related to the concept of planning are those sequential tasks in which the subject is free to choose his own order of responding, but must not make the same response twice. Here the left frontal lobe plays the major role, a finding consistent with the notion of left-hemisphere dominance for the programming of voluntary actions. In contrast, the right frontal lobe appears to be more critically involved in monitoring the temporal sequence of externally ordered events, although the verbal or non-verbal nature of the stimuli remains a relevant factor.

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Visually guided saccade versus eye-hand reach: contrasting neuronal activity in the cortical supplementary and frontal eye fields

Journal of Neurophysiology ◽

10.1152/jn.1996.75.5.2187 ◽

1996 ◽

Vol 75 (5) ◽

pp. 2187-2191 ◽

Cited By ~ 68

Author(s):

H. Mushiake ◽

N. Fujii ◽

J. Tanji

Keyword(s):

Eye Movement ◽

Neuronal Activity ◽

Motor Task ◽

Oculomotor Control ◽

Frontal Eye Field ◽

Frontal Eye Fields ◽

Saccadic Eye Movement ◽

Visually Guided ◽

Supplementary Eye Field ◽

Eye Field

1. We studied neuronal activity in the supplementary eye field (SEF) and frontal eye field (FEF) of a monkey during performance of a conditional motor task that required capturing of a target either with a saccadic eye movement (the saccade-only condition) or with an eye-hand reach (the saccade-and-reach condition), according to visual instructions. 2. Among 106 SEF neurons that showed presaccadic activity, more than one-half of them (54%) were active preferentially under the saccade-only condition (n = 12) or under the saccade-and-reach condition (n = 45), while the remaining 49 neurons were equally active in both conditions. 3. By contrast, most (97%) of the 109 neurons in the FEF exhibited approximately equal activity in relation to saccades under the two conditions. 4. The present results suggest the possibility that SEF neurons, at least in part, are involved in signaling whether the motor task is oculomotor or combined eye-arm movements, whereas FEF neurons are mostly related to oculomotor control.

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Gaze Palsy as a Manifestation of Todd’s Phenomenon: Case Report and Review of the Literature

Brain Sciences ◽

10.3390/brainsci10050298 ◽

2020 ◽

Vol 10 (5) ◽

pp. 298

Author(s):

Karmele Olaciregui Dague ◽

Manuel Dafotakis ◽

Jörg B. Schulz ◽

Rainer Surges

Keyword(s):

Subarachnoid Hemorrhage ◽

Clonic Seizure ◽

Frontal Eye Field ◽

Correct Identification ◽

Eye Field ◽

Narrative Literature Review ◽

Stroke Mimic ◽

Therapeutic Decision Making ◽

The Right ◽

Gaze Palsy

Background: Though Todd’s phenomenon (TP) is a relatively rare occurrence, its correct identification is of key diagnostic and therapeutic importance as a stroke mimic. Here we describe a case of isolated gaze palsy as a manifestation of TP, discuss periictal gaze abnormalities as lateralizing sign involving the frontal eye field (FEF), and present a narrative literature review. Methods: We reviewed the main features of the case and conducted a structured literature search of TP and gaze palsy using PubMed. We restricted the search to publications in English, Spanish, French, and German. Case presentation: A 71-year-old male with a history of right frontotemporal subarachnoid hemorrhage was admitted to the Emergency Department of our institution after suffering a first unprovoked focal to bilateral tonic-clonic seizure with ictal gaze deviation to the left. Cranial imaging showed no signs of ischemia, intracerebral hemorrhage, or tumor. The patient presented the following postictal features: involuntary eye deviation to the right due to left-sided gaze palsy and disorientation in time with preserved responsiveness. Eye movements were normal three days later. We concluded that the patient suffered from new-onset epilepsy due to sequelae following the right frontotemporal subarachnoid hemorrhage, affecting the FEF with contralateral ictal gaze deviation, and postictal gaze palsy with ipsilateral eye deviation as an unusual Todd’s phenomenon. Conclusion: Unusual manifestations of TP are uncommon but clinically highly relevant, as they can mimic stroke or epileptic status and are decisive in the diagnostic and therapeutic decision-making process. Though postictal gaze palsy has been reported associated with other deficits, this constitutes, to our knowledge, the first report of isolated gaze palsy as a form of TP. Further research into the underlying causes is needed. Ictal contralateral gaze and head deviation, and probably postictal ipsilateral gaze deviation if present, are very helpful for the lateralization of the seizure-onset zone.

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Alien Hand Sign and Other Cognitive Deficits following Ruptured Aneurysm of the Anterior Communicating Artery

Behavioural Neurology ◽

10.1155/1991/419342 ◽

1991 ◽

Vol 4 (3) ◽

pp. 167-179 ◽

Cited By ~ 9

Author(s):

Alan J. Parkin ◽

Caroline Barry

Keyword(s):

Frontal Lobe ◽

Memory Loss ◽

Ruptured Aneurysm ◽

Anterior Communicating Artery ◽

Left Frontal Lobe ◽

Left Hand ◽

Functional Locus ◽

Alien Hand ◽

And Performance ◽

The Right

We describe a right-handed patient who suffered a ruptured aneurysm of the anterior communicating artery (ACoA) which was clipped successfully. Computerized tomography indicated a low density area in the genu of the corpus callosum and the infero-lateral aspect of the left frontal lobe. On recovery the patient's most notable deficit was the “alien hand sign” whereby the left hand would frequently interfere with the actions of the right hand. Problems in response initiation were also evident. There was significant memory loss and performance was impaired on some tests of frontal lobe function. Discussion centres on the functional locus of the alien hand sign but other aspects of the patient's deficits are also considered.

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Post-Stimulation Effect of Electroacupuncture at Yintang (EX-HN3) and GV20 on cerebral functional regions in healthy volunteers: A resting functional MRI study

Acupuncture in Medicine ◽

10.1136/acupmed-2011-010123 ◽

2012 ◽

Vol 30 (4) ◽

pp. 307-315 ◽

Cited By ~ 8

Author(s):

Yu Zheng ◽

Shanshan Qu ◽

Na Wang ◽

Limin Liu ◽

Guanzhong Zhang ◽

...

Keyword(s):

Frontal Lobe ◽

Temporal Lobe ◽

Parietal Lobe ◽

Occipital Lobe ◽

Cingulate Gyrus ◽

Left Frontal Lobe ◽

Posterior Cingulate Gyrus ◽

Functional Regions ◽

Limbic Lobe ◽

The Right

Objective The aim of the present work was to observe the activation/deactivation of cerebral functional regions after electroacupuncture (EA) at Yintang (EX-HN3) and GV20 by functional MRI (fMRI). Design A total of 12 healthy volunteers were stimulated by EA at Yintang and GV20 for 30 min. Resting-state fMRI scans were performed before EA, and at 5 and 15 min after needle removal. Statistical parametric mapping was used to preprocess initial data, and regional homogeneity (ReHo) and amplitude of low-frequency fluctuation (ALFF) were analysed. Results ReHo at 5 min post stimulation showed increases in the left temporal lobe and cerebellum and decreases in the left parietal lobe, occipital lobe and right precuneus. At 15 min post stimulation, ReHo showed increases in the left fusiform gyrus; lingual gyrus; middle temporal gyrus; postcentral gyrus; limbic lobe; cingulate gyrus; paracentral lobule; cerebellum, posterior lobe, declive; right cuneus and cerebellum, anterior lobe, culmen. It also showed decreases in the left frontal lobe, parietal lobe, right temporal lobe, frontal lobe, parietal lobe and right cingulate gyrus. ALFF at 5 min post stimulation showed increases in the right temporal lobe, but decreases in the right limbic lobe and posterior cingulate gyrus. At 15 min post stimulation ALFF showed increases in the left frontal lobe, parietal lobe, occipital lobe, right temporal lobe, parietal lobe, occipital lobe and cerebellum, but decreases in the left frontal lobe, anterior cingulate gyrus, right frontal lobe and posterior cingulate gyrus. Conclusions After EA stimulation at Yintang and GV20, which are associated with psychiatric disorder treatments, changes were localised in the frontal lobe, cingulate gyrus and cerebellum. Changes were higher in number and intensity at 15 min than at 5 min after needle removal, demonstrating lasting and strong after-effects of EA on cerebral functional regions.

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Occipital activations and deactivations induced by stimulation of the right human frontal eye field

Journal of Vision ◽

10.1167/5.8.365 ◽

2010 ◽

Vol 5 (8) ◽

pp. 365-365

Author(s):

C. C. Ruff ◽

F. Blankenburg ◽

O. Bjoertomt ◽

S. Bestmann ◽

J.-D. Haynes ◽

...

Keyword(s):

Frontal Eye Field ◽

Eye Field ◽

The Right ◽

Stimulation Of

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Right frontal eye field has perceptual and oculomotor functions during optokinetic stimulation and nystagmus

Journal of Neurophysiology ◽

10.1152/jn.00468.2019 ◽

2020 ◽

Vol 123 (2) ◽

pp. 571-586 ◽

Cited By ~ 1

Author(s):

Angela Mastropasqua ◽

James Dowsett ◽

Marianne Dieterich ◽

Paul C. J. Taylor

Keyword(s):

Eye Movements ◽

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Visual Motion ◽

Optokinetic Nystagmus ◽

Frontal Eye Field ◽

Optokinetic Stimulation ◽

Motion Discrimination ◽

Eye Field ◽

The Right

The right frontal eye field (rFEF) is associated with visual perception and eye movements. rFEF is activated during optokinetic nystagmus (OKN), a reflex that moves the eye in response to visual motion (optokinetic stimulation, OKS). It remains unclear whether rFEF plays causal perceptual and/or oculomotor roles during OKS and OKN. To test this, participants viewed a leftward-moving visual scene of vertical bars and judged whether a flashed dot was moving. Single pulses of transcranial magnetic stimulation (TMS) were applied to rFEF on half of trials. In half of blocks, to explore oculomotor control, participants performed an OKN in response to the OKS. rFEF TMS, during OKN, made participants more accurate on trials when the dot was still, and it slowed eye movements. In separate blocks, participants fixated during OKS. This not only controlled for eye movements but also allowed the use of EEG to explore the FEF’s role in visual motion discrimination. In these blocks, by contrast, leftward dot motion discrimination was impaired, associated with a disruption of the frontal-posterior balance in alpha-band oscillations. None of these effects occurred in a control site (M1) experiment. These results demonstrate multiple related yet dissociable causal roles of the right FEF during optokinetic stimulation. NEW & NOTEWORTHY This study demonstrates causal roles of the right frontal eye field (FEF) in motion discrimination and eye movement control during visual scene motion: previous work had only examined other stimuli and eye movements such as saccades. Using combined transcranial magnetic stimulation and EEG and a novel optokinetic stimulation motion-discrimination task, we find evidence for multiple related yet dissociable causal roles within the FEF: perceptual processing during optokinetic stimulation, generation of the optokinetic nystagmus, and the maintenance of alpha oscillations.

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Suppression of Task-Related Saccades by Electrical Stimulation in the Primate's Frontal Eye Field

Journal of Neurophysiology ◽

10.1152/jn.1997.77.5.2252 ◽

1997 ◽

Vol 77 (5) ◽

pp. 2252-2267 ◽

Cited By ~ 87

Author(s):

Douglas D. Burman ◽

Charles J. Bruce

Keyword(s):

Electrical Stimulation ◽

Eye Movements ◽

Frontal Lobe ◽

Premotor Cortex ◽

Saccadic Eye Movements ◽

Association Cortex ◽

Frontal Eye Field ◽

Visually Guided ◽

Low Intensity ◽

Eye Field

Burman, Douglas D. and Charles J. Bruce. Suppression of task-related saccades by electrical stimulation in the primate's frontal eye field. J. Neurophysiol. 77: 2252–2267, 1997. Patients with frontal lobe damage have difficulty suppressing reflexive saccades to salient visual stimuli, indicating that frontal lobe neocortex helps to suppress saccades as well as to produce them. In the present study, a role for the frontal eye field (FEF) in suppressing saccades was demonstrated in macaque monkeys by application of intracortical microstimulation during the performance of a visually guided saccade task, a memory prosaccade task, and a memory antisaccade task. A train of low-intensity (20–50 μA) electrical pulses was applied simultaneously with the disappearance of a central fixation target, which was always the cue to initiate a saccade. Trials with and without stimulation were compared, and significantly longer saccade latencies on stimulation trials were considered evidence of suppression. Low-intensity stimulation suppressed task-related saccades at 30 of 77 sites tested. In many cases saccades were suppressed throughout the microstimulation period (usually 450 ms) and then executed shortly after the train ended. Memory-guided saccades were most dramatically suppressed and were often rendered hypometric, whereas visually guided saccades were less severely suppressed by stimulation. At 18 FEF sites, the suppression of saccades was the only observable effect of electrical stimulation. Contraversive saccades were usually more strongly suppressed than ipsiversive ones, and cells recorded at such purely suppressive sites commonly had either foveal receptive fields or postsaccadic responses. At 12 other FEF sites at which saccadic eye movements were elicited at low thresholds, task-related saccades whose vectors differed from that of the electrically elicited saccade were suppressed by electrical stimulation. Such suppression at saccade sites was observed even with currents below the threshold for eliciting saccades. Pure suppression sites tended to be located near or in the fundus, deeper in the anterior bank of the arcuate than elicited saccade sites. Stimulation in the prefrontal association cortex anterior to FEF did not suppress saccades, nor did stimulation in premotor cortex posterior to FEF. These findings indicate that the primate FEF can help orchestrate saccadic eye movements by suppressing inappropriate saccade vectors as well as by selecting, specifying, and triggering appropriate saccades. We hypothesize that saccades could be suppressed both through local FEF interactions and through FEF projections to subcortical regions involved in maintaining fixation.

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Timing of Target Discrimination in Human Frontal Eye Fields

Journal of Cognitive Neuroscience ◽

10.1162/0898929041502634 ◽

2004 ◽

Vol 16 (6) ◽

pp. 1060-1067 ◽

Cited By ~ 113

Author(s):

Jacinta O'Shea ◽

Neil G. Muggleton ◽

Alan Cowey ◽

Vincent Walsh

Keyword(s):

Visual Processing ◽

Time Window ◽

Time Windows ◽

Cell Activity ◽

Correct Rejection ◽

Frontal Eye Field ◽

Search Performance ◽

Target Discrimination ◽

Eye Field ◽

The Right

Frontal eye field (FEF) neurons discharge in response to behaviorally relevant stimuli that are potential targets for saccades. Distinct visual and motor processes have been dissociated in the FEF of macaque monkeys, but little is known about the visual processing capacity of FEF in humans. We used double-pulse transcranial magnetic stimulation [(d)TMS] to investigate the timing of target discrimination during visual conjunction search. We applied dual TMS pulses separated by 40 msec over the right FEF and vertex. These were applied in five timing conditions to sample separate time windows within the first 200 msec of visual processing. (d)TMS impaired search performance, reflected in reduced d′ scores. This effect was limited to a time window between 40 and 80 msec after search array onset. These parameters correspond with single-cell activity in FEF that predicts monkeys' behavioral reports on hit, miss, false alarm, and correct rejection trials. Our findings demonstrate a crucial early role for human FEF in visual target discrimination that is independent of saccade programming.

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