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Helmchen C, Machner B, Schwenke H, Sprenger A. Bilateral lesion of the cerebellar fastigial nucleus: Effects on smooth pursuit acceleration and non-reflexive visually-guided saccades. Front Neurol 2022; 13:883213. [PMID: 36203994 PMCID: PMC9530709 DOI: 10.3389/fneur.2022.883213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
Background“Central dizziness” due to acute bilateral midline cerebellar disease sparing the posterior vermis has specific oculomotor signs. The oculomotor region of the cerebellar fastigial nucleus (FOR) crucially controls the accuracy of horizontal visually-guided saccades and smooth pursuit eye movements. Bilateral FOR lesions elicit bilateral saccade hypermetria with preserved pursuit. It is unknown whether the initial acceleration of smooth pursuit is impaired in patients with bilateral FOR lesions.ObjectiveWe studied the effect of a cerebellar lesion affecting the deep cerebellar nuclei on the initial horizontal pursuit acceleration and investigated whether saccade dysmetria also affects other types of volitional saccades, i.e., memory-guided saccades and anti-saccades, which are not performed in immediate response to the visual target.MethodsWe recorded eye movements during a sinusoidal and step-ramp target motion paradigm as well as visually-guided saccades, memory-guided saccades, and anti-saccades in one patient with a circumscribed cerebellar hemorrhage and 18 healthy control subjects using a video-based eye tracker.ResultsThe lesion comprised the FOR bilaterally but spared the posterior vermis. The initial pursuit acceleration was low but not significantly different from the healthy control subjects and sinusoidal pursuit was normal. Bilateral saccade hypermetria was not only seen with visually-guided saccades but also with anti-saccades and memory-guided saccades. The final eye position remained accurate.ConclusionWe provide new insights into the contribution of the bilateral deep cerebellar nuclei on the initial acceleration of human smooth pursuit in midline cerebellar lesions. In line with experimental bilateral FOR lesion data in non-human primates, the initial pursuit acceleration in our patient was not significantly reduced, in contrast to the effects of unilateral experimental FOR lesions. Working memory and neural representation of target locations seem to remain unimpaired. Our data argue against an impaired common command feeding the circuits controlling saccadic and pursuit eye movements and support the hypothesis of independent influences on the neural processes generating both types of eye movements in the deep cerebellar nuclei.
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Affiliation(s)
- Christoph Helmchen
- Department of Neurology, University Hospitals Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
- Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
- *Correspondence: Christoph Helmchen
| | - Björn Machner
- Department of Neurology, University Hospitals Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
- Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
| | - Hannes Schwenke
- Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
- Department of Neuroradiology, University Hospitals Schleswig-Holstein, Lübeck, Germany
| | - Andreas Sprenger
- Department of Neurology, University Hospitals Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
- Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
- Institute of Psychology II, University of Lübeck, Lübeck, Germany
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King S, Chen AL, Joshi A, Serra A, Leigh RJ. Effects of cerebellar disease on sequences of rapid eye movements. Vision Res 2011; 51:1064-74. [PMID: 21385592 PMCID: PMC3084368 DOI: 10.1016/j.visres.2011.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Revised: 02/21/2011] [Accepted: 02/22/2011] [Indexed: 10/18/2022]
Abstract
Studying saccades can illuminate the more complex decision-making processes required for everyday movements. The double-step task, in which a target jumps to two successive locations before the subject has time to react, has proven a powerful research tool to investigate the brain's ability to program sequential responses. We asked how patients with a range of cerebellar disorders responded to the double-step task, specifically, whether the initial saccadic response made to a target is affected by the appearance of a second target jump. We also sought to determine whether cerebellar patients were able to make corrective saccades towards the remembered second target location if it were turned off soon after presentation. We tested saccades to randomly interleaved single- and double-step target jumps to eight locations on a circle. Patient's initial responses to double-step stimuli showed 50% more error than saccades to single target jumps, and often, they failed to make a saccade to the first target jump. The presence of a second target jump had similar, but smaller effects in control subjects (error increased by 18%). During memory-guided double-step trials, both patients and controls made corrective saccades in darkness to the remembered location of the second jump. We conclude that in cerebellar patients, the second target jump interferes with programming of the saccade to the first target jump of a double-step stimulus; this defect highlights patients' impaired ability to respond appropriately to sudden, conflicting changes in their environment. Conversely, since cerebellar patients can make corrective memory-guided saccades in darkness, they retain the ability to remember spatial locations, possibly due to non-retinal neural signals (corollary discharge) from cerebral hemispheric areas concerned with spatial localization.
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Affiliation(s)
- Susan King
- Department of Neurology, Veterans Affairs Medical Center and Case Western Reserve University, Cleveland, OH, 44106-5040 USA
| | - Athena L. Chen
- Department of Neurology, Veterans Affairs Medical Center and Case Western Reserve University, Cleveland, OH, 44106-5040 USA
| | - Anand Joshi
- Department of Neurology, Veterans Affairs Medical Center and Case Western Reserve University, Cleveland, OH, 44106-5040 USA
| | - Alessandro Serra
- Department of Neurology, Veterans Affairs Medical Center and Case Western Reserve University, Cleveland, OH, 44106-5040 USA
| | - R. John Leigh
- Department of Neurology, Veterans Affairs Medical Center and Case Western Reserve University, Cleveland, OH, 44106-5040 USA
- Department of Biomedical Engineering, Veterans Affairs Medical Center and Case Western Reserve University, Cleveland, OH, 44106-5040 USA
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Kumar AN, Han YH, Liao K, Rucker JC, Ramat S, Leigh RJ. Evaluating Large Saccades in Patients with Brain-Stem or Cerebellar Disorders. Ann N Y Acad Sci 2006; 1039:404-16. [PMID: 15826993 DOI: 10.1196/annals.1325.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Clinicians conventionally test saccades at the bedside by noting the accuracy, initiation time, and speed of large movements, with the patient's head stationary. Partly for methodological reasons, laboratory analysis of saccades has mainly focused on movements of 20 degrees or less. By measuring the velocity waveform of large saccades, it is possible to examine more closely the way in which brain stem and cerebellum guide the eye to the target. Large saccades made by healthy humans show a positively skewed velocity profile. Slow saccades made by patients with brain-stem disorders show a prolonged plateau of low velocity. Some patients with cerebellar disorders may show increased acceleration and deceleration of saccades. Each of these velocity waveforms can be modeled by changing the parameters that describe medium-lead burst neuron firing. In certain other brain-stem and cerebellar disorders, transient decelerations or premature terminations of saccades occur; such velocity waveforms cannot be modeled solely by changing the parameters that describe burst neuron firing. Instead, it is necessary to postulate dysfunction of the mechanism that normally inhibits pontine omnipause neurons, thereby permitting burst neurons to discharge until the saccade is completed. Analysis of large, abnormal saccades calls for application of novel techniques to identify the beginning and end of the saccadic pulse command.
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Affiliation(s)
- Arun N Kumar
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106-1702, USA
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Pélisson D, Goffart L, Guillaume A. Control of saccadic eye movements and combined eye/head gaze shifts by the medio-posterior cerebellum. PROGRESS IN BRAIN RESEARCH 2003; 142:69-89. [PMID: 12693255 DOI: 10.1016/s0079-6123(03)42007-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The cerebellar areas involved in the control of saccades have recently been identified in the medio-posterior cerebellum (MPC). Unit activity recordings, experimental lesions and electrical microstimulation of this region in cats and monkeys have provided a considerable amount of data and allowed the development of new computational models. In this paper, we review these data and concepts about cerebellar function, discuss their importance and limitations and suggest future directions for research. The anatomical data indicate that the MPC has more than one site of action in the visuo-oculomotor system. In contrast, most models emphasize the role of cerebellar connections with immediate pre-oculomotor circuits in the reticular formation, and only one recent model also incorporates the ascending projections of the MPC to the superior colliculus. A major challenge for future studies, in continuation with this initial attempt, is to determine whether the various cerebellar output pathways correspond to distinct contributions to the control of saccadic eye movements. Also, a series of recent studies in the cat have indicated a more general role of the MPC in the control of orienting movements in space, calling for an increasing effort to the study of the MPC in the production of head-unrestrained saccadic gaze shifts.
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Affiliation(s)
- Denis Pélisson
- INSERM Unité 534, 16 avenue Doyen Lépine, 69500 Bron, France.
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Gross HM, Heinze A, Seiler T, Stephan V. Generative character of perception: a neural architecture for sensorimotor anticipation. Neural Netw 1999; 12:1101-1129. [PMID: 12662648 DOI: 10.1016/s0893-6080(99)00047-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The basic idea of our anticipatory approach to perception is to avoid the common separation of perception and generation of behavior and to fuse both aspects into a consistent neural process. Our approach tries to explain the phenomenon of perception, in particular, of perception at the level of sensorimotor intelligence, from a behavior-oriented point of view. Perception is assumed to be a generative process of anticipating the course of events resulting from alternative sequences of hypothetically executed actions. By means of this sensorimotor anticipation, it is possible to characterize a visual scenery immediately in categories of behavior, i.e. by a set of actions which describe possible methods of interaction with the objects in the environment. Thus, the competence to perceive a complex situation can be understood as the capability to anticipate the course of events caused by different action sequences. Starting from an abstract description of anticipatory perception and the essential biological evidence for internal simulation, we present two biologically motivated computational models that are able to anticipate and evaluate hypothetically sensorimotor sequences. Both models consider functional aspects of those cortical and subcortical systems that are assumed to be involved in the process of sensory prediction and sensorimotor control. Our first approach, the Model for Anticipation based on Sensory IMagination (MASIM), realizes a sequential search in sensorimotor space using a simple model of lateral cerebellum as sensory predictor. We demonstrate the efficiency of this model approach in the light of visually guided local navigation behaviors of a mobile system. The second approach, the Model for Anticipation based on Cortical Representations (MACOR), is actually still at a conceptual level of realization. We postulate that this model allows a completely parallel search at the neocortical level using assemblies of spiking neurons for grouping, separation, and selection of sensorimotor sequences. Both models are intended as general schemes for anticipation based perception at the level of sensorimotor intelligence.
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Affiliation(s)
- H -M. Gross
- Department of Neuroinformatics, Technical University Ilmenau, D-98684, Ilmenau, Germany
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Leigh RJ, Ramat S. Neuropharmacologic aspects of the ocular motor system and the treatment of abnormal eye movements. Curr Opin Neurol 1999; 12:21-7. [PMID: 10097880 DOI: 10.1097/00019052-199902000-00004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Neuropharmacology is aiding our understanding of the control of eye movements in at least three ways. First, neurotransmitters have been identified in the pathways that coordinate gaze. Second, the technique of pharmacologic inactivation has provided a powerful method to determine the contributions of populations of neurons to specific behaviors, such as steady gaze holding. Finally, the results of basic neuropharmacologic studies have been used to identify candidate drugs for therapeutic trials of abnormal eye movements.
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Affiliation(s)
- R J Leigh
- Department of Neurology, Veterans Affairs Medical Center, Cleveland, Ohio, USA.
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