1
|
Sunyer-Grau B, Quevedo L, Rodríguez-Vallejo M, Argilés M. Comitant strabismus etiology: extraocular muscle integrity and central nervous system involvement-a narrative review. Graefes Arch Clin Exp Ophthalmol 2023; 261:1781-1792. [PMID: 36680614 PMCID: PMC10271888 DOI: 10.1007/s00417-022-05935-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 11/09/2022] [Accepted: 12/01/2022] [Indexed: 01/22/2023] Open
Abstract
Strabismus is not a condition in itself but the consequence of an underlying problem. Eye misalignment can be caused by disease, injury, and/or abnormalities in any of the structures and processes involved in visual perception and oculomotor control, from the extraocular muscles and their innervations to the oculomotor and visual processing areas in the brain. A small percentage of all strabismus cases are the consequence of well-described genetic syndromes, acquired insult, or disease affecting the extraocular muscles (EOMs) or their innervations. We will refer to them as strabismus of peripheral origin since their etiology lies in the peripheral nervous system. However, in most strabismus cases, that is comitant, non-restrictive, non-paralytic strabismus, the EOMs and their innervations function properly. These cases are not related to specific syndromes and their precise causes remain poorly understood. They are generally believed to be caused by deficits in the central neural pathways involved in visual perception and oculomotor control. Therefore, we will refer to them as central strabismus. The goal of this narrative review is to discuss the possible causes behind this particular type of eye misalignment and to raise awareness among eyecare professionals about the important role the central nervous system plays in strabismus etiology, and the subsequent implications regarding its treatment. A non-systematic search was conducted using PubMed, Medline, Cochrane, and Google Scholar databases with the keywords "origins," "causes," and "etiology" combined with "strabismus." A snowball approach was also used to find relevant references. In the following article, we will first describe EOM integrity in central strabismus; next, we will address numerous reasons that support the idea of central nervous system (CNS) involvement in the origin of the deviation, followed by listing several possible central causes of the ocular misalignment. Finally, we will discuss the implications CNS etiology has on strabismus treatment.
Collapse
Affiliation(s)
- Bernat Sunyer-Grau
- School of Optics and Optometry, Universitat Politècnica de Catalunya, Terrassa, Spain
| | - Lluïsa Quevedo
- School of Optics and Optometry, Universitat Politècnica de Catalunya, Terrassa, Spain
| | | | - Marc Argilés
- School of Optics and Optometry, Universitat Politècnica de Catalunya, Terrassa, Spain
| |
Collapse
|
2
|
Paduca A, Lundmark PO, Bruenech JR. Does Surgical Resection of Horizontal Extraocular Muscles Disrupt Ocular Proprioceptors? Clin Ophthalmol 2023; 17:1395-1405. [PMID: 37214153 PMCID: PMC10198280 DOI: 10.2147/opth.s381247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 04/06/2023] [Indexed: 05/24/2023] Open
Abstract
Purpose It has been promoted that disturbance of ocular proprioception may play a role in the pathogenesis of concomitant strabismus and other types of oculomotor anomalies. The aim of the study was to obtain knowledge about how surgical foreshortening of the myotendinous region potentially affects the proprioceptors that resides in this area of the muscles and to test the hypothesis that avoiding disruption of ocular proprioceptors result in a more favorable long term postoperative result. Patients and Methods The distal end of the lateral and medial rectus muscles from patients with manifest concomitant strabismus with a deviation of ≥15 prism diopters (PD) were collected during strabismus surgery and processed for light microscopy by standard histochemical techniques. Histological analysis served to differentiate between the tissue samples containing pure tendon, versus samples containing the myotendinous junction. Criteria for successful outcome was defined as a residual angle of deviation less than 10 PD. The binocular status of the patient was measured pre- and post-operatively at 6-months of follow-up. Results Tissue samples from 43 patients (median age 19 years old, range 3-58 years) were collected during surgery. Twenty-six of the samples contained pure tendon, while 17 contained muscle fibres. The evolution of the post-operative result revealed a moderate reduction in the residual angle of deviation in patient-samples containing pure tendon. In contrast, the residual angle of deviation clearly increased in patient-samples containing muscle fibres. The difference between the two groups reached statistical significance after 6 months. Successful outcome was found to be more than three times more likely in cases where surgery was performed in pure tendon, compared to muscle fibres. Conclusion The current study supports the hypothesis that avoiding disruption of ocular proprioceptors, located in the distal myotendinous region, results in a more favorable postoperative result.
Collapse
Affiliation(s)
- Ala Paduca
- Ophthalmology Department, State University of Medicine and Pharmacy Nicolae Testemitanu, Chisinau, Republic of Moldova
| | - Per O Lundmark
- Department of Optometry, Radiography and Lighting Design, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway
| | - J Richard Bruenech
- Department of Optometry, Radiography and Lighting Design, Faculty of Health and Social Sciences, University of South-Eastern Norway, Kongsberg, Norway
| |
Collapse
|
3
|
Balslev D, Mitchell AG, Faria PJM, Priba L, Macfarlane JA. Proprioceptive contribution to oculomotor control in humans. Hum Brain Mapp 2022; 43:5081-5090. [PMID: 36135800 DOI: 10.1002/hbm.26080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 08/11/2022] [Accepted: 08/22/2022] [Indexed: 11/08/2022] Open
Abstract
Stretch receptors in the extraocular muscles (EOMs) inform the central nervous system about the rotation of one's own eyes in the orbits. Whereas fine control of the skeletal muscles hinges critically on proprioceptive feedback, the role of proprioception in oculomotor control remains unclear. Human behavioural studies provide evidence for EOM proprioception in oculomotor control, however, behavioural and electrophysiological studies in the macaque do not. Unlike macaques, humans possess numerous muscle spindles in their EOMs. To find out whether the human oculomotor nuclei respond to proprioceptive feedback we used functional magnetic resonance imaging (fMRI). With their eyes closed, participants placed their right index finger on the eyelid at the outer corner of the right eye. When prompted by a sound, they pushed the eyeball gently and briefly towards the nose. Control conditions separated out motor and tactile task components. The stretch of the right lateral rectus muscle was associated with activation of the left oculomotor nucleus and subthreshold activation of the left abducens nucleus. Because these nuclei control the horizontal movements of the left eye, we hypothesized that proprioceptive stimulation of the right EOM triggered left eye movement. To test this, we followed up with an eye-tracking experiment in complete darkness using the same behavioural task as in the fMRI study. The left eye moved actively in the direction of the passive displacement of the right eye, albeit with a smaller amplitude. Eye tracking corroborated neuroimaging findings to suggest a proprioceptive contribution to ocular alignment.
Collapse
Affiliation(s)
- Daniela Balslev
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | | | - Patrick J M Faria
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Lukasz Priba
- Clinical Research Centre, Ninewells Hospital, Dundee, UK
| | - Jennifer A Macfarlane
- Clinical Research Centre, Ninewells Hospital, Dundee, UK.,Medical Physics Department, NHS Tayside, Ninewells Hospital, Dundee, UK
| |
Collapse
|
4
|
Sonkodi B, Resch MD, Hortobágyi T. Is the Sex Difference a Clue to the Pathomechanism of Dry Eye Disease? Watch out for the NGF-TrkA-Piezo2 Signaling Axis and the Piezo2 Channelopathy. J Mol Neurosci 2022; 72:1598-1608. [PMID: 35507012 PMCID: PMC9374789 DOI: 10.1007/s12031-022-02015-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 04/20/2022] [Indexed: 01/11/2023]
Abstract
Dry eye disease (DED) is a multifactorial disorder with recognized pathology, but not entirely known pathomechanism. It is suggested to represent a continuum with neuropathic corneal pain with the paradox that DED is a pain-free disease in most cases, although it is regarded as a pain condition. The current paper puts into perspective that one gateway from physiology to pathophysiology could be a Piezo2 channelopathy, opening the pathway to a potentially quad-phasic non-contact injury mechanism on a multifactorial basis and with a heterogeneous clinical picture. The primary non-contact injury phase could be the pain-free microinjury of the Piezo2 ion channel at the corneal somatosensory nerve terminal. The secondary non-contact injury phase involves harsher corneal tissue damage with C-fiber contribution due to the lost or inadequate intimate cross-talk between somatosensory Piezo2 and peripheral Piezo1. The third injury phase of this non-contact injury is the neuronal sensitization process with underlying repeated re-injury of the Piezo2, leading to the proposed chronic channelopathy. Notably, sensitization may evolve in certain cases in the absence of the second injury phase. Finally, the quadric injury phase is the lingering low-grade neuroinflammation associated with aging, called inflammaging. This quadric phase could clinically initiate or augment DED, explaining why increasing age is a risk factor. We highlight the potential role of the NGF-TrkA axis as a signaling mechanism that could further promote the microinjury of the corneal Piezo2 in a stress-derived hyperexcited state. The NGF-TrkA-Piezo2 axis might explain why female sex represents a risk factor for DED.
Collapse
Affiliation(s)
- Balázs Sonkodi
- Department of Health Sciences and Sport Medicine, Hungarian University of Sports Science, Budapest, Hungary.
| | - Miklós D Resch
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Tibor Hortobágyi
- Institute of Pathology, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Insitute of Psychiatry Psychology and Neuroscience, King's College London, London, UK.,Center for Age-Related Medicine, SESAM, Stavanger University Hospital, Stavanger, Norway
| |
Collapse
|
5
|
Sonkodi B, Hortobágyi T. Amyotrophic lateral sclerosis and delayed onset muscle soreness in light of the impaired blink and stretch reflexes – watch out for Piezo2. Open Med (Wars) 2022; 17:397-402. [PMID: 35340618 PMCID: PMC8898040 DOI: 10.1515/med-2022-0444] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal, multisystem neurodegenerative disease that causes the death of motoneurons (MNs) progressively and eventually leads to paralysis. In contrast, delayed onset muscle soreness (DOMS) is defined as delayed onset soreness, muscle stiffness, loss of force-generating capacity, reduced joint range of motion, and decreased proprioceptive function. Sensory deficits and impaired proprioception are common symptoms of both ALS and DOMS, as impairment at the proprioceptive sensory terminals in the muscle spindle is theorized to occur in both. The important clinical distinction is that extraocular muscles (EOM) are relatively spared in ALS, in contrast to limb skeletal muscles; however, the blink reflex goes through a gradual impairment in a later stage of disease progression. Noteworthy is, that, the stretch of EOM induces the blink reflex. The current authors suggest that the impairment of proprioceptive sensory nerve terminals in the EOM muscle spindles are partially responsible for lower blink reflex, beyond central origin, and implies the critical role of Piezo2 ion channels and Wnt-PIP2 signaling in this pathomechanism. The proposed microinjury of Piezo2 on muscle spindle proprioceptive terminals could provide an explanation for the painless dying-back noncontact injury mechanism theory of ALS.
Collapse
Affiliation(s)
- Balázs Sonkodi
- Department of Health Sciences and Sport Medicine, University of Physical Education , Budapest , Hungary
| | - Tibor Hortobágyi
- ELKH-DE Cerebrovascular and Neurodegenerative Research Group, Department of Neurology, University of Debrecen , Debrecen , Hungary
- Department of Pathology, Faculty of Medicine, University of Szeged , Szeged , Hungary
- Department of Old Age Psychiatry, Psychology and Neuroscience, King’s College London , London , UK
- Center for Age-Related Medicine, SESAM, Stavanger University Hospital , Stavanger , Norway
| |
Collapse
|
6
|
Zieliński G, Filipiak Z, Ginszt M, Matysik-Woźniak A, Rejdak R, Gawda P. The Organ of Vision and the Stomatognathic System-Review of Association Studies and Evidence-Based Discussion. Brain Sci 2021; 12:brainsci12010014. [PMID: 35053758 PMCID: PMC8773770 DOI: 10.3390/brainsci12010014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/14/2021] [Accepted: 12/21/2021] [Indexed: 11/16/2022] Open
Abstract
The stomatognathic system is a functional complex of tissues and organs located within the oral and craniofacial cavities. The craniofacial anatomical factors and the biomechanics of the temporomandibular joints affect many systems throughout the body, including the organ of vision. However, few scientific reports have shown a relationship between the organ of vision and the stomatognathic system. The purpose of this review is to provide an overview of connections along neural, muscle-fascial, and biochemical pathways between the organ of vision and the stomatognathic system. Based on the literature presented in this review, the connections between the organ of vision and the stomatognathic system seem undeniable. Understanding the anatomical, physiological, and biochemical interrelationships may allow to explain the interactions between the mentioned systems. According to the current knowledge, it is not possible to indicate the main linking pathway; presumably, it may be a combination of several presented pathways. The awareness of this relationship among dentists, ophthalmologists, physiotherapists, and optometrists should increase for the better diagnosis and treatment of patients.
Collapse
Affiliation(s)
- Grzegorz Zieliński
- Department of Sports Medicine, Medical University of Lublin, 20-093 Lublin, Poland;
- Correspondence:
| | - Zuzanna Filipiak
- Department of Nephrology, Dialysis and Internal Medicine, Medical University of Warsaw, 02-091 Warsaw, Poland;
| | - Michał Ginszt
- Department of Rehabilitation and Physiotherapy, Medical University of Lublin, 20-093 Lublin, Poland;
| | - Anna Matysik-Woźniak
- Department of General and Pediatric Ophthalmology, Medical University of Lublin, 20-093 Lublin, Poland; (A.M.-W.); (R.R.)
| | - Robert Rejdak
- Department of General and Pediatric Ophthalmology, Medical University of Lublin, 20-093 Lublin, Poland; (A.M.-W.); (R.R.)
| | - Piotr Gawda
- Department of Sports Medicine, Medical University of Lublin, 20-093 Lublin, Poland;
| |
Collapse
|
7
|
Puja G, Sonkodi B, Bardoni R. Mechanisms of Peripheral and Central Pain Sensitization: Focus on Ocular Pain. Front Pharmacol 2021; 12:764396. [PMID: 34916942 PMCID: PMC8669969 DOI: 10.3389/fphar.2021.764396] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/09/2021] [Indexed: 12/14/2022] Open
Abstract
Persistent ocular pain caused by corneal inflammation and/or nerve injury is accompanied by significant alterations along the pain axis. Both primary sensory neurons in the trigeminal nerves and secondary neurons in the spinal trigeminal nucleus are subjected to profound morphological and functional changes, leading to peripheral and central pain sensitization. Several studies using animal models of inflammatory and neuropathic ocular pain have provided insight about the mechanisms involved in these maladaptive changes. Recently, the advent of new techniques such as optogenetics or genetic neuronal labelling has allowed the investigation of identified circuits involved in nociception, both at the spinal and trigeminal level. In this review, we will describe some of the mechanisms that contribute to the perception of ocular pain at the periphery and at the spinal trigeminal nucleus. Recent advances in the discovery of molecular and cellular mechanisms contributing to peripheral and central pain sensitization of the trigeminal pathways will be also presented.
Collapse
Affiliation(s)
- Giulia Puja
- Department of Life Sciences, University of Modena and Reggio Emilia, Emilia-Romagna, Italy
| | - Balazs Sonkodi
- Department of Health Sciences and Sport Medicine, University of Physical Education, Budapest, Hungary
| | - Rita Bardoni
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Emilia-Romagna, Italy
| |
Collapse
|
8
|
Vasudeva A, Dhakal R, Vupparaboina KK, Verkicharla PK. Do rectus muscle parameters vary between emmetropes and myopes? Ophthalmic Physiol Opt 2021; 41:1300-1307. [PMID: 34549823 DOI: 10.1111/opo.12890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 08/13/2021] [Accepted: 08/16/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE This study investigated the thickness, area, and insertion site of the medial (MR) and lateral (LR) rectus muscles in individuals with emmetropia and different degrees of myopia. METHODS Swept-source optical coherence tomography images of the MR and LR muscles in 80 participants including emmetropes (spherical equivalent refractive error [SER] ±0.50 D, N = 14) and myopes (≤ -0.75 D, N = 66), were analysed. Custom-designed, semi-automated software was used to measure parameters such as insertion distance from limbus, muscle thickness at every 1 mm interval to 3 mm periphery and muscle area from insertion site to 3 mm. RESULTS The median (Q1, Q3) SER error and axial length were -6.00 D (-13.25, -2.12) and 25.78 mm (23.78, 28.61), respectively. The MR was significantly thinner (mean ± SE: 137.7 ± 8.9 vs. 159.7 ± 8.9 µm, p < 0.01) and occupied less area than the LR (0.35 ± 0.01 vs. 0.42 ± 0.01 mm2 , respectively, p < 0.01). The thickness of the MR gradually increased from the insertion site to a 3 mm peripheral eccentric location (106.5 3.8 µm at 1 mm, 135.5 ± 4.5 µm at 2 mm and 156.1 ± 5.9 µm at 3 mm, p < 0.01). The overall median thickness of the MR was significantly less in myopes (129 µm [111.5, 152.2]) than emmetropes (158.1 [134.3, 167.7] µm, p = 0.03). However, no such trend was seen in the LR muscle. Muscle area and insertion distance were not different between emmetropes and myopes in both horizontal rectus muscles. CONCLUSION Unlike the LR, the parameters of the MR (thin and occupying less area) show significant association with myopia. While the key finding of this study indicates the possible association of MR parameters with myopia, the clinical relevance of this finding and its role in myopiogenesis/progression needs to be investigated further.
Collapse
Affiliation(s)
- Ashish Vasudeva
- Myopia Research Lab, Brien Holden Institute of Optometry and Vision Sciences, Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
| | - Rohit Dhakal
- Myopia Research Lab, Brien Holden Institute of Optometry and Vision Sciences, Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
| | - Kiran Kumar Vupparaboina
- Ophthalmic Engineering Group, LVPEI Centre for Innovation, L V Prasad Eye Institute, Hyderabad, India
| | - Pavan K Verkicharla
- Myopia Research Lab, Brien Holden Institute of Optometry and Vision Sciences, Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
| |
Collapse
|
9
|
Balzarotti S, Cavaletti F, D'Aloia A, Colombo B, Cardani E, Ciceri MR, Antonietti A, Eugeni R. The Editing Density of Moving Images Influences Viewers' Time Perception: The Mediating Role of Eye Movements. Cogn Sci 2021; 45:e12969. [PMID: 33844350 DOI: 10.1111/cogs.12969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 02/26/2021] [Accepted: 03/04/2021] [Indexed: 11/29/2022]
Abstract
The present study examined whether cinematographic editing density affects viewers' perception of time. As a second aim, based on embodied models that conceive time perception as strictly connected to the movement, we tested the hypothesis that the editing density of moving images also affects viewers' eye movements and that these later mediate the effect of editing density on viewers' temporal judgments. Seventy participants watched nine video clips edited by manipulating the number of cuts (slow- and fast-paced editing against a master shot, unedited condition). For each editing density, multiple video clips were created, representing three different kinds of routine actions. The participants' eye movements were recorded while watching the video, and the participants were asked to report duration judgments and subjective passage of time judgments after watching each clip. The results showed that participants subjectively perceived that time flew more while watching fast-paced edited videos than slow-paced or unedited videos; by contrast, concerning duration judgments, participants overestimated the duration of fast-paced videos compared to the master-shot videos. Both the slow- and the fast-paced editing generated shorter fixations than the master shot, and the fast-paced editing led to shorter fixations than the slow-paced editing. Finally, compared to the unedited condition, editing led to an overestimation of durations through increased eye mobility. These findings suggest that the editing density of moving images by increasing the number of cuts effectively altered viewers' experience of time and add further evidence to prior research showing that performed eye movement is associated with temporal judgments.
Collapse
Affiliation(s)
| | | | - Adriano D'Aloia
- Department of Letters, Philosophy, Communication, University of Bergamo
| | | | - Elisa Cardani
- Department of Psychology, Università Cattolica del Sacro Cuore
| | | | | | - Ruggero Eugeni
- Department of Communication and Performing Arts, Università Cattolica del Sacro Cuore
| |
Collapse
|
10
|
Feldman AG, Zhang L. Eye and head movements and vestibulo-ocular reflex in the context of indirect, referent control of motor actions. J Neurophysiol 2020; 124:115-133. [PMID: 32490708 PMCID: PMC7474454 DOI: 10.1152/jn.00076.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/06/2020] [Accepted: 05/23/2020] [Indexed: 01/03/2023] Open
Abstract
Conventional explanations of the vestibulo-ocular reflex (VOR) and eye and head movements are revisited by considering two alternative frameworks addressing the question of how the brain controls motor actions. Traditionally, biomechanical and/or computational frameworks reflect the views of several prominent scholars of the past, including Helmholtz and von Holst, who assumed that the brain directly specifies the desired motor outcome and uses efference copy to influence perception. However, empirical studies resulting in the theory of referent control of action and perception (an extension of the equilibrium-point hypothesis) revealed that direct specification of motor outcome is inconsistent with nonlinear properties of motoneurons and with the physical principle that the brain can control motor actions only indirectly, by changing or maintaining the values of neurophysiological parameters that influence, but can remain independent of, biomechanical variables. Some parameters are used to shift the origin (referent) points of spatial frames of reference (FRs) or system of coordinates in which motor actions emerge without being predetermined. Parameters are adjusted until the emergent motor actions meet the task demands. Several physiological parameters and spatial FRs have been identified, supporting the notion of indirect, referent control of movements. Instead of integration of velocity-dependent signals, position-dimensional referent signals underlying head motion can likely be transmitted to motoneurons of extraocular muscles. This would produce compensatory eye movement preventing shifts in gaze during head rotation, even after bilateral destruction of the labyrinths. The referent control framework symbolizes a shift in the paradigm for the understanding of VOR and eye and head movement production.
Collapse
Affiliation(s)
- Anatol G Feldman
- Department of Neuroscience, University of Montreal, Montreal, Quebec, Canada
| | - Lei Zhang
- Institut für Neuroinformatik, Ruhr-Universität Bochum, Bochum, Germany
| |
Collapse
|
11
|
Quercia P, Pozzo T, Marino A, Guillemant AL, Cappe C, Gueugneau N. Children with Dyslexia Have Altered Cross-Modal Processing Linked to Binocular Fusion. A Pilot Study. Clin Ophthalmol 2020; 14:437-448. [PMID: 32103890 PMCID: PMC7025670 DOI: 10.2147/opth.s226690] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 01/27/2020] [Indexed: 01/16/2023] Open
Abstract
Introduction The cause of dyslexia, a reading disability characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities, is unknown. A considerable body of evidence shows that dyslexics have phonological disorders. Other studies support a theory of altered cross-modal processing with the existence of a pan-sensory temporal processing deficit associated with dyslexia. Learning to read ultimately relies on the formation of automatic multisensory representations of sounds and their written representation while eyes fix a word or move along a text. We therefore studied the effect of brief sounds on vision with a modification of binocular fusion at the same time (using the Maddox Rod test). Methods To check if the effect of sound on vision is specific, we first tested with sounds and then replaced them with proprioceptive stimulation on 8 muscular sites. We tested two groups of children composed respectively of 14 dyslexic children and 10 controls. Results The results show transient visual scotoma (VS) produced by sensory stimulations associated with the manipulation of oculomotor balance, the effect being drastically higher in the dyslexic group. The spatial distribution of the VS is stochastic. The effect is not specific for sounds but exists also with proprioceptive stimulations. Discussion Although there was a very significant difference between the two groups, we were not able to correlate the (VS) occurrence with the dyslexic’s reading performance. One possibility to confirm the link between VS and reading impairment would be to find a specific treatment reducing the occurrence of the VS and to check its effect on dyslexia.
Collapse
Affiliation(s)
- Patrick Quercia
- Université de Bourgogne, Dijon, Campus Universitaire, UFR STAPS, BP 27877, F-21078 Dijon, France; INSERM U1093, Cognition, Action et Plasticité Sensorimotrice, Dijon F-21078, France
| | - Thierry Pozzo
- Center for Translational Neurophysiology, Istituto Italiano di Tecnologia, Ferrara, Italy
| | | | - Anne Laure Guillemant
- Université de Bourgogne, Dijon, Campus Universitaire, UFR STAPS, BP 27877, F-21078 Dijon, France; INSERM U1093, Cognition, Action et Plasticité Sensorimotrice, Dijon F-21078, France
| | - Céline Cappe
- Brain and Cognition Research Center, CerCo, CNRS UMR 5549, Toulouse, France
| | - Nicolas Gueugneau
- Université de Bourgogne, Dijon, Campus Universitaire, UFR STAPS, BP 27877, F-21078 Dijon, France; INSERM U1093, Cognition, Action et Plasticité Sensorimotrice, Dijon F-21078, France
| |
Collapse
|
12
|
The effect of prism adaptation on state estimates of eye position in the orbit. Cortex 2019; 115:246-263. [DOI: 10.1016/j.cortex.2019.02.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 10/10/2018] [Accepted: 02/07/2019] [Indexed: 11/23/2022]
|
13
|
Bohlen MO, Warren S, May PJ. A central mesencephalic reticular formation projection to medial rectus motoneurons supplying singly and multiply innervated extraocular muscle fibers. J Comp Neurol 2017; 525:2000-2018. [PMID: 28177529 DOI: 10.1002/cne.24187] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 01/10/2017] [Accepted: 01/11/2017] [Indexed: 12/20/2022]
Abstract
We recently demonstrated a bilateral projection to the supraoculomotor area from the central mesencephalic reticular formation (cMRF), a region implicated in horizontal gaze changes. C-group motoneurons, which supply multiply innervated fibers in the medial rectus muscle, are located within the primate supraoculomotor area, but their inputs and function are poorly understood. Here, we tested whether C-group motoneurons in Macaca fascicularis monkeys receive a direct cMRF input by injecting this portion of the reticular formation with anterograde tracers in combination with injection of retrograde tracer into the medial rectus muscle. The results indicate that the cMRF provides a dense, bilateral projection to the region of the medial rectus C-group motoneurons. Numerous close associations between labeled terminals and each multiply innervated fiber motoneuron were present. Within the oculomotor nucleus, a much sparser ipsilateral projection onto some of the A- and B- group medial rectus motoneurons that supply singly innervated fibers was observed. Ultrastructural analysis demonstrated a direct synaptic linkage between anterogradely labeled reticular terminals and retrogradely labeled medial rectus motoneurons in all three groups. These findings reinforce the notion that the cMRF is a critical hub for oculomotility by proving that it contains premotor neurons supplying horizontal extraocular muscle motoneurons. The differences between the cMRF input patterns for C-group versus A- and B-group motoneurons suggest the C-group motoneurons serve a different oculomotor role than the others. The similar patterns of cMRF input to C-group motoneurons and preganglionic Edinger-Westphal motoneurons suggest that medial rectus C-group motoneurons may play a role in accommodation-related vergence.
Collapse
Affiliation(s)
- Martin O Bohlen
- Program in Neuroscience, University of Mississippi Medical Center, Jackson, Mississippi
| | - Susan Warren
- Department of Neurobiology & Anatomical Sciences, University of Mississippi Medical Center, Jackson, Mississippi
| | - Paul J May
- Department of Neurobiology & Anatomical Sciences, University of Mississippi Medical Center, Jackson, Mississippi.,Department of Ophthalmology, University of Mississippi Medical Center, Jackson, Mississippi.,Department of Neurology, University of Mississippi Medical Center, Jackson, Mississippi
| |
Collapse
|
14
|
Bohlen MO, Warren S, Mustari MJ, May PJ. Examination of feline extraocular motoneuron pools as a function of muscle fiber innervation type and muscle layer. J Comp Neurol 2016; 525:919-935. [PMID: 27588695 DOI: 10.1002/cne.24111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/08/2016] [Accepted: 08/18/2016] [Indexed: 01/13/2023]
Abstract
This study explores two points related to the pattern of innervation of the extraocular muscles. First, species differences exist in the location of the motoneurons supplying multiply innervated fibers (MIFs) and singly innervated fibers (SIFs) in eye muscles. MIF motoneurons are located outside the extraocular nuclei in primates, but are intermixed with SIF motoneurons within rat extraocular nuclei. To test whether this difference is related to visual capacity and frontal placement of eyes, we injected retrograde tracers into the medial rectus muscle of the cat, a highly visual nonprimate with frontally placed eyes. Distal injections labeled smaller MIF motoneurons located ventrolaterally and rostrally within the oculomotor nucleus (III). More central injections also labeled a separate population of larger cells located dorsally in III. Thus, the cat shares with the nocturnal rat the feature of having MIF motoneurons located within the bounds of III. On the other hand, just as with monkeys, cats show segregation of the MIF and SIF medial rectus motoneuron pools, albeit in a different pattern. Second, extraocular muscles are divided into two layers; the inner, global layer inserts into the sclera, and the outer, orbital layer inserts into the connective tissue pulley. To test whether these layers are supplied by anatomically discrete motoneuron pools, we injected tracer into the orbital layer of the cat lateral rectus muscle. No evidence of either morphological or distributional differences was found, suggesting that the functional differences in these layers may be due mainly to their orbital anatomy, not their innervation. J. Comp. Neurol. 525:919-935, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Martin O Bohlen
- Program in Neuroscience, University of Mississippi Medical Center, Jackson, Mississippi, 39216
| | - Susan Warren
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, Mississippi, 39216
| | - Michael J Mustari
- National Primate Research Center, University of Washington, Seattle, Washington, 98195
| | - Paul J May
- Department of Neurobiology and Anatomical Sciences, University of Mississippi Medical Center, Jackson, Mississippi, 39216.,Department of Ophthalmology, University of Mississippi Medical Center, Jackson, Mississippi, 39216.,Department of Neurology, University of Mississippi Medical Center, Jackson, Mississippi, 39216
| |
Collapse
|
15
|
Ni J, Tatalovic M, Straumann D, Olasagasti I. Gaze direction affects linear self-motion heading discrimination in humans. Eur J Neurosci 2013; 38:3248-60. [DOI: 10.1111/ejn.12324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 06/25/2013] [Accepted: 06/26/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Jianguang Ni
- Department of Neurology; University Hospital Zürich; Zürich Switzerland
| | - Milos Tatalovic
- Department of Neurology; University Hospital Zürich; Zürich Switzerland
| | - Dominik Straumann
- Department of Neurology; University Hospital Zürich; Zürich Switzerland
| | - Itsaso Olasagasti
- Department of Neurology; University Hospital Zürich; Zürich Switzerland
| |
Collapse
|
16
|
McCamy MB, Collins N, Otero-Millan J, Al-Kalbani M, Macknik SL, Coakley D, Troncoso XG, Boyle G, Narayanan V, Wolf TR, Martinez-Conde S. Simultaneous recordings of ocular microtremor and microsaccades with a piezoelectric sensor and a video-oculography system. PeerJ 2013; 1:e14. [PMID: 23638348 PMCID: PMC3629042 DOI: 10.7717/peerj.14] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 01/03/2013] [Indexed: 11/20/2022] Open
Abstract
Our eyes are in continuous motion. Even when we attempt to fix our gaze, we produce so called "fixational eye movements", which include microsaccades, drift, and ocular microtremor (OMT). Microsaccades, the largest and fastest type of fixational eye movement, shift the retinal image from several dozen to several hundred photoreceptors and have equivalent physical characteristics to saccades, only on a smaller scale (Martinez-Conde, Otero-Millan & Macknik, 2013). OMT occurs simultaneously with drift and is the smallest of the fixational eye movements (∼1 photoreceptor width, >0.5 arcmin), with dominant frequencies ranging from 70 Hz to 103 Hz (Martinez-Conde, Macknik & Hubel, 2004). Due to OMT's small amplitude and high frequency, the most accurate and stringent way to record it is the piezoelectric transduction method. Thus, OMT studies are far rarer than those focusing on microsaccades or drift. Here we conducted simultaneous recordings of OMT and microsaccades with a piezoelectric device and a commercial infrared video tracking system. We set out to determine whether OMT could help to restore perceptually faded targets during attempted fixation, and we also wondered whether the piezoelectric sensor could affect the characteristics of microsaccades. Our results showed that microsaccades, but not OMT, counteracted perceptual fading. We moreover found that the piezoelectric sensor affected microsaccades in a complex way, and that the oculomotor system adjusted to the stress brought on by the sensor by adjusting the magnitudes of microsaccades.
Collapse
Affiliation(s)
- Michael B McCamy
- Department of Neurobiology, Barrow Neurological Institute, USA.,School of Mathematical and Statistical Sciences, Arizona State University, USA
| | | | - Jorge Otero-Millan
- Department of Neurobiology, Barrow Neurological Institute, USA.,Department of Signal Theory and Communications, University of Vigo, Spain
| | | | - Stephen L Macknik
- Department of Neurosurgery, Barrow Neurological Institute, USA.,Department of Neurobiology, Barrow Neurological Institute, USA
| | - Davis Coakley
- Trinity College Dublin, Dublin 2, Ireland.,St. James's Hospital(Mercer's Institute for Research in Ageing), Ireland
| | - Xoana G Troncoso
- Department of Neurobiology, Barrow Neurological Institute, USA.,Unité de Neuroscience, Information et Complexité (CNRS-UNIC), France
| | - Gerard Boyle
- St James's Hospital(Medical Physics and Bioengineering Dept.), Ireland
| | | | - Thomas R Wolf
- Neuro-Ophthalmology Unit, Barrow Neurological Institute, USA.,Neuro-Ophthalmology Consultation: Barnett-Dulaney-Perkins Eye Center, USA
| | | |
Collapse
|
17
|
Lee TE, Kim SH, Cho YA. Postoperative changes in spatial localization following exotropia surgery. Curr Eye Res 2012; 38:210-4. [PMID: 22870922 DOI: 10.3109/02713683.2012.713151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To measure changes in spatial localization following exotropia surgery using a computer touch-screen method of measurement. METHODS Enrolled in the study were 60 exotropia patients, all of whom had undergone corrective muscle surgeries under general anesthesia: 37 patients had undergone unilateral lateral rectus or bilateral lateral rectus muscle recession procedures (recession group) and 23 patients had undergone unilateral lateral and medial rectus muscle resection (R&R), or unilateral medial rectus resection only (resection group). We evaluated spatial localization by having patients point to targets on a computer touch-screen before surgery, and 1 day and 1 month after surgery. The pointing error, Δp, is defined as the difference between the actual location of the target and the pointed-to location of the target by unsigned value, was recorded as the mean of five tests. We compared the extent of postoperative changes in Δp between the two groups. RESULTS The mean Δp before surgery did not differ statistically between the two groups (p = 0.93). One day after surgery, however, the postoperative change in Δp of the resection group compared with that of the recession group (2.0 ± 0.7° and 0.4 ± 0.5°, respectively) was significant (p = 0.01 and p = 0.86 respectively). CONCLUSIONS The ability for spatial localization is decreased in patients immediately following medial rectus resection, but is regained by 1 month following surgery.
Collapse
Affiliation(s)
- Tae-Eun Lee
- Department of Ophthalmology, Korea University College of Medicine, Seoul, South Korea
| | | | | |
Collapse
|
18
|
Eye proprioception may provide real time eye position information. Neurol Sci 2012; 34:281-6. [PMID: 22872063 DOI: 10.1007/s10072-012-1172-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Accepted: 07/24/2012] [Indexed: 12/21/2022]
Abstract
Because of the frequency of eye movements, online knowledge of eye position is crucial for the accurate spatial perception and behavioral navigation. Both the internal monitoring signal (corollary discharge) of eye movements and the eye proprioception signal are thought to contribute to the localization of the eye position in the orbit. However, the functional role of these two eye position signals in spatial cognition has been disputed for more than a century. The predominant view proposes that the online analysis of eye position is exclusively provided by the corollary discharge signal, while the eye proprioception signal only plays a role in the long-term calibration of the oculomotor system. However, increasing evidence from recent behavioral and physiological studies suggests that the eye proprioception signal may play a role in the online monitoring of eye position. The purpose of this review is to discuss the feasibility and possible function of the eye proprioceptive signal for online monitoring of eye position.
Collapse
|
19
|
da Silva Costa RM, Kung J, Poukens V, Demer JL. Nonclassical innervation patterns in mammalian extraocular muscles. Curr Eye Res 2012; 37:761-9. [PMID: 22559851 DOI: 10.3109/02713683.2012.676699] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE The abducens (CN6) and oculomotor (CN3) nerves (nn) enter target extraocular muscles (EOMs) via their global surfaces; the trochlear (CN4) nerve enters the superior oblique (SO) muscle on its orbital surface. Motor nn are classically described as entering the EOMs in their middle thirds. We investigated EOM innervation that does not follow the classic pattern. METHODS Intact, whole orbits of two humans and one each monkey, cow, and rabbit were paraffin embedded, serially sectioned in coronal plane, and prepared with Masson's trichrome and by choline acetyltransferase (ChAT) immunohistochemistry. Nerves innervating EOMs were traced from the orbital apex toward the scleral insertion, and some were reconstructed in three dimensions. RESULTS Classical motor nn positive for ChAT entered rectus and SO EOMs and coursed anteriorly, without usually exhibiting recurrent branches. In every orbit, nonclassical (NC) nn entered each EOM well posterior to classical motor nn. These NC nn entered and arborized in the posterior EOMs, mainly within the orbital layer (OL), but often traveled into the global layer or entered an adjacent EOM. Other NC nn originated in the orbital apex and entered each EOM through its orbital surface, ultimately anastomosing with classical motor nn. Mixed sensory and motor nn interconnected EOM spindles. CONCLUSIONS EOMs exhibit a previously undescribed pattern of NC innervation originating in the proximal orbit that partially joins branches of the classical motor nn. This NC innervation appears preferential for the OL, and may have mixed supplemental motor and/or proprioceptive functions, perhaps depending upon species. The origin of the NC innervation is currently unknown.
Collapse
Affiliation(s)
- Roberta M da Silva Costa
- Department of Ophthalmology, University of California-Los Angeles, Jules Stein Eye Institute, 100 Stein Plaza, Los Angeles, CA 90095-7002, USA
| | | | | | | |
Collapse
|
20
|
Pandey PK, Rathi N, Singh A, Sharma A, Shinde V, Sharma S, Sinha E. Primary superior oblique muscle-levator muscle synkinesis. J AAPOS 2012; 16:214-5; author reply 215-6. [PMID: 22525188 DOI: 10.1016/j.jaapos.2011.12.155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 12/12/2011] [Accepted: 12/13/2011] [Indexed: 11/18/2022]
|
21
|
Abstract
Experimental and theoretical research into cerebellar function has begun to converge toward understanding the cerebellum as a "controller" in the engineering sense. The purpose of a controller is to convert high-level intent commands and information describing the current state of a system into low-level control signals suitable for maintaining or changing system behavior. The cerebellar subsystem appears to play this role for parts of the body and other parts of the brain. As with engineering controllers, fundamental functions include stabilization at a fixed posture or state, adjustment of movement or transition amplitude, facilitation of movement/transition speed and crispness of launch and braking, improvement of resistance to disturbances, coordination of control across multiple degrees of freedom, and assistance with estimation and/or prediction of current and future system states. As with adaptive engineering controllers, the cerebellar subsystem also readily tunes itself over time. At a more detailed level, many of the specific actions of cerebellar circuits can be understood in terms of proportional (P), integrator-like (I), and differentiator-like (D) signal processing which are fundamental components of many engineering control systems. This chapter presents an integrated, mechanistic view of ataxia, tremor, and several cerebellar oculomotor signs in terms of PID control and the neural centers that appear to subserve these functions. It also suggests the manner in which impairments in motor learning, perception, and cognition that are associated with cerebellar dysfunction may be viewed from a similar perspective.
Collapse
Affiliation(s)
- Steve G Massaquoi
- Harvard Medical School and Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA.
| |
Collapse
|
22
|
Manivannan M, Suresh PK. On the somatosensation of vision. Ann Neurosci 2012; 19:31-9. [PMID: 25205961 PMCID: PMC4117078 DOI: 10.5214/ans.0972.7531.180409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Revised: 12/30/2011] [Accepted: 01/06/2012] [Indexed: 11/23/2022] Open
Abstract
The interconnection between vision and somatosensation is already well-established and is further supplemented by the evolutionary link between eyes and photoreceptors, and the functional connection between photosensation and thermoreception. However, our analysis shows that the relation between vision and somatosensation is much deeper and suggests that somatosensation may possibly be the basis of vision. Surprisingly, our photoreceptor itself needs somatosensory proteins for its functioning, and our entire visual pathway depends on somatosensory cues for its functioning.
Collapse
Affiliation(s)
- M Manivannan
- Department of Applied Mechanics, IIT Madras, Chennai, TN 600 036
| | | |
Collapse
|
23
|
Does orbital proprioception contribute to gaze stability during translation? Exp Brain Res 2011; 215:77-87. [PMID: 21947173 DOI: 10.1007/s00221-011-2873-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 09/08/2011] [Indexed: 10/17/2022]
Abstract
Translational motion induces retinal image slip which varies with object distance. The brain must know binocular eye position in real time in order to scale eye movements so as to minimize retinal slip. Two potential sources of eye position information are orbital proprioception and an internal representation of eye position derived from central ocular motor signals. To examine the role of orbital proprioceptive information, the position of the left eye was perturbed by microstimulation of the left abducens nerve during translational motion to the right or left along the interaural axis in two rhesus macaques. Microstimulation rotated the eye laterally, activating eye muscle proprioceptors, while keeping central motor commands undisturbed. We found that microstimulation-induced eye position changes did not affect the translational VOR in the abductive (lateral rectus) direction, but it did influence the responses in the adductive (medial rectus) direction. Our findings demonstrate that proprioceptive inputs appear to be involved in the TVOR responses at least during ipsilateral head movements and proprioceptive influences on the TVOR may involve vergence-related signals to the oculomotor nucleus. However, internal representation of eye position, derived from central ocular motor signals, likely plays the dominant role in providing eye position information for scaling eye movements during translational motion, particularly in the abducent direction.
Collapse
|
24
|
The time course of online trajectory corrections in memory-guided saccades. Exp Brain Res 2011; 212:457-69. [PMID: 21660466 DOI: 10.1007/s00221-011-2752-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 05/25/2011] [Indexed: 12/25/2022]
Abstract
Recent investigations have revealed the kinematics of horizontal saccades are less variable near the end of the trajectory than during the course of execution. Converging evidence indicates that oculomotor networks use online sensorimotor feedback to correct for initial trajectory errors. It is also known that oculomotor networks express saccadic corrections with decreased efficiency when responses are made toward memorized locations. The present research investigated whether repetitive motor timekeeping influences online feedback-based corrections in predictive saccades. Predictive saccades are a subclass of memory-guided saccades and are observed when one makes series of timed saccades. We hypothesized that cueing predictive saccades in a sequence would facilitate the expression of trajectory corrections. Seven participants produced a number of single unpaced, visually guided saccades, and also sequences of timed predictive saccades. Kinematic and trajectory variability were used to measure the expression of online saccadic corrections at a number of time indices in saccade trajectories. In particular, we estimated the minimum time required to implement feedback-based corrections, which was consistently 37 ms. Our observations demonstrate that motor commands in predictive memory-guided saccades can be parameterized by spatial working memory and retain the accuracy of online trajectory corrections typically associated with visually guided behavior. In contrast, untimed memory-guided saccades exhibited diminished kinematic evidence for online corrections. We conclude that motor timekeeping and sequencing contributed to efficient saccadic corrections. These results contribute to an evolving view of the interactions between motor planning and spatial working memory, as they relate to oculomotor control.
Collapse
|
25
|
Xu Y, Wang X, Peck C, Goldberg ME. The time course of the tonic oculomotor proprioceptive signal in area 3a of somatosensory cortex. J Neurophysiol 2011; 106:71-7. [PMID: 21346201 DOI: 10.1152/jn.00668.2010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A proprioceptive representation of eye position exists in area 3a of primate somatosensory cortex (Wang X, Zhang M, Cohen IS, Goldberg ME. Nat Neurosci 10: 640-646, 2007). This eye position signal is consistent with a fusimotor response (Taylor A, Durbaba R, Ellaway PH, Rawlinson S. J Physiol 571: 711-723, 2006) and has two components during a visually guided saccade task: a short-latency phasic response followed by a tonic response. While the early phasic response can be excitatory or inhibitory, it does not accurately reflect the eye's orbital position. The late tonic response appears to carry the proprioceptive eye position signal, but it is not clear when this component emerges and whether the onset of this signal is reliable. To test the temporal dynamics of the tonic proprioceptive signal, we used an oculomotor smooth pursuit task in which saccadic eye movements and phasic proprioceptive responses are suppressed. Our results show that the tonic proprioceptive eye position signal consistently lags the actual eye position in the orbit by ~60 ms under a variety of eye movement conditions. To confirm the proprioceptive nature of this signal, we also studied the responses of neurons in a vestibuloocular reflex (VOR) task in which the direction of gaze was held constant; response profiles and delay times were similar in this task, suggesting that this signal does not represent angle of gaze and does not receive visual or vestibular inputs. The length of the delay suggests that the proprioceptive eye position signal is unlikely to be used for online visual processing for action, although it could be used to calibrate an efference copy signal.
Collapse
Affiliation(s)
- Yixing Xu
- Mahoney-Keck Center for Brain and Behavior Research, Department of Neuroscience, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | | | | | | |
Collapse
|
26
|
Kerhuel L, Viollet S, Franceschini N. Steering by Gazing: An Efficient Biomimetic Control Strategy for Visually Guided Micro Aerial Vehicles. IEEE T ROBOT 2010. [DOI: 10.1109/tro.2010.2042537] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
27
|
Matheron E, Kapoula Z. Vertical phoria and postural control in upright stance in healthy young subjects. Clin Neurophysiol 2008; 119:2314-20. [PMID: 18760665 DOI: 10.1016/j.clinph.2008.06.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Revised: 06/17/2008] [Accepted: 06/26/2008] [Indexed: 12/14/2022]
|
28
|
Wang N, May PJ. Peripheral muscle targets and central projections of the mesencephalic trigeminal nucleus in macaque monkeys. Anat Rec (Hoboken) 2008; 291:974-87. [PMID: 18461596 DOI: 10.1002/ar.20712] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The mesencephalic trigeminal nucleus (MesV) contains the somata of primary afferent neurons that innervate muscle spindles in masticatory muscles and mechanoreceptors in the periodontal ligaments. There are conflicting reports about additional peripheral targets of MesV, such as the extraocular muscles, as well as about its central targets. In addition, only limited primate data are available. Consequently, we examined MesV projections in macaque monkeys. The retrograde tracer wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was injected into masticatory or extraocular muscles to define the peripheral targets of the primate MesV. Numerous labeled neurons were found in ipsilateral MesV after masticatory muscle injections. The scattered distribution of labeled cells, and their presence among clusters of unlabeled cells, suggests the muscle representations overlap. Just a few MesV neurons were labeled after extraocular muscle injections. This correlates with the small number of muscle spindles present in macaque extraocular muscles, suggesting MesV cells supplying extraocular muscle spindles may contribute a minor component to oculomotor proprioception. To examine the central connections of MesV, biotinylated dextran amine (BDA) was injected into the spinal trigeminal nucleus (Vs). The presence of retrogradely labeled MesV cells indicated a projection to Vs from MesV. These injections also anterogradely labeled terminals that lay in close association with MesV cells, suggesting an ascending projection from Vs to MesV. Finally, a small number of MesV neurons were labeled after WGA-HRP injections into the upper cervical spinal cord. This pattern of central connections indicates MesV and Vs information is combined to guide mastication.
Collapse
Affiliation(s)
- Niping Wang
- Department of Anatomy, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA
| | | |
Collapse
|
29
|
Matheron E, Yang Q, Lê TT, Kapoula Z. Effects of ocular dominance on the vertical vergence induced by a 2-diopter vertical prism during standing. Neurosci Lett 2008; 444:176-80. [PMID: 18718507 DOI: 10.1016/j.neulet.2008.08.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2008] [Revised: 08/04/2008] [Accepted: 08/10/2008] [Indexed: 10/21/2022]
Abstract
This study examined the eye movement responses to vertical disparity induced by a 2-diopter vertical prism base down while in standing position. Vertical vergence movements are known to be small requiring accurate measurement with the head stabilized, and was done with the EyeLink 2. The 2-diopter vertical prism, base down, was inserted in front of either the non-dominant eye (NDE) or dominant eye (DE) at 40 and 200 cm. The results showed that vertical vergence was stronger and excessive relative to the required value (i.e. 1.14 degrees ) when the prism was on the NDE for both distances, but more appropriate when the prism was on the DE. The results suggest that sensory disparity process and vertical vergence responses are modulated by eye dominance.
Collapse
Affiliation(s)
- Eric Matheron
- Service d'Ophtalmologie. Hôpital Européen Georges Pompidou, Paris Cedex 15, France.
| | | | | | | |
Collapse
|
30
|
Les présentations cliniques. OSTÉOPATHIE PÉDIATRIQUE 2007. [PMCID: PMC7271215 DOI: 10.1016/b978-2-84299-917-9.50007-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
31
|
Abstract
Human extraocular muscles are richly endowed with sensory receptors. The precise role of afferent signals derived from these proprioceptors in ocular motor control and spatial localization has been the subject of considerable debate for more than a century. Laboratory-based and clinical studies have increasingly suggested that proprioceptive signals from extraocular muscles influence visuomotor behavior.
Collapse
Affiliation(s)
- Clifford R Weir
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow G12 0YN, United Kingdom.
| |
Collapse
|
32
|
Semrau JA, Wei M, Angelaki DE, Angelaki D. Scaling of the fore-aft vestibulo-ocular reflex by eye position during smooth pursuit. J Neurophysiol 2006; 96:936-40. [PMID: 16641384 DOI: 10.1152/jn.00185.2006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
An eye position signal scales the amplitude of compensatory eye velocity in the translational vestibulo-ocular reflex (TVOR). To investigate the origin of such a modulatory signal, we studied the kinematics of the fore-aft TVOR as rhesus monkeys pursued a horizontally moving target at velocities between 0.5 and 30 degrees /s. We found that the "V-shaped" curve of the fore-aft TVOR amplitude as a function of eye position was shifted opposite to the direction of pursuit eye movement. As a result, the tip of the V-shaped curve that occurred close to zero eye position during steady-state fixation was shifted to the right during leftward pursuit and to the left during rightward pursuit eye movements. The faster the pursuit velocity the larger the observed shift. These results suggest that the scaling of the TVOR can precede actual eye position changes by several tens of milliseconds, which averaged 169 +/- 87 ms in three rhesus monkeys. Thus, central motor commands, rather than low-level efference copy or proprioceptive information, may be the signals scaling TVOR amplitude.
Collapse
Affiliation(s)
- Jennifer A Semrau
- Department of Anatomy and Neurobiology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | | | | | | |
Collapse
|
33
|
Blohm G, Optican LM, Lefèvre P. A model that integrates eye velocity commands to keep track of smooth eye displacements. J Comput Neurosci 2006; 21:51-70. [PMID: 16633937 DOI: 10.1007/s10827-006-7199-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Revised: 01/12/2006] [Accepted: 01/13/2006] [Indexed: 12/20/2022]
Abstract
Past results have reported conflicting findings on the oculomotor system's ability to keep track of smooth eye movements in darkness. Whereas some results indicate that saccades cannot compensate for smooth eye displacements, others report that memory-guided saccades during smooth pursuit are spatially correct. Recently, it was shown that the amount of time before the saccade made a difference: short-latency saccades were retinotopically coded, whereas long-latency saccades were spatially coded. Here, we propose a model of the saccadic system that can explain the available experimental data. The novel part of this model consists of a delayed integration of efferent smooth eye velocity commands. Two alternative physiologically realistic neural mechanisms for this integration stage are proposed. Model simulations accurately reproduced prior findings. Thus, this model reconciles the earlier contradictory reports from the literature about compensation for smooth eye movements before saccades because it involves a slow integration process.
Collapse
Affiliation(s)
- Gunnar Blohm
- CESAME, Université catholique de Louvain, 4, avenue G. Lemaître, 1348, Louvain-la-Neuve, Belgium.
| | | | | |
Collapse
|
34
|
Wang Z, Dell'Osso LF, Zhang Z, Leigh RJ, Jacobs JB. Tenotomy does not affect saccadic velocities: support for the "small-signal" gain hypothesis. Vision Res 2006; 46:2259-67. [PMID: 16497352 DOI: 10.1016/j.visres.2006.01.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 12/22/2005] [Accepted: 01/11/2006] [Indexed: 11/15/2022]
Abstract
We investigated the effects of four-muscle tenotomy on saccadic characteristics in infantile nystagmus syndrome (INS) and acquired pendular nystagmus (APN). Eye movements of 10 subjects with INS and one with APN were recorded using infrared reflection, magnetic search coil, or high-speed digital video. The expanded nystagmus acuity function (NAFX) quantified tenotomy-induced foveation changes in the INS. Saccadic characteristics and peak-to-peak nystagmus amplitudes were measured. Novel statistical tests were performed on the saccadic data. Six out of the 10 INS subjects showed no changes in saccadic duration, peak velocity, acceleration, or trajectory. In the other four, the differences were less than in peak-to-peak amplitudes (from 14.6% to 39.5%) and NAFX (from 22.2% to 162.4%). The APN subject also showed no changes despite a 50% decrease in peak-to-peak amplitude and a 34% increase in NAFX. The "small-signal" changes (peak-to-peak nystagmus amplitude and NAFX) were found to far exceed any "large-signal" changes (saccadic). Tenotomy successfully reduced INS and APN, enabling higher visual acuity without adversely affecting saccadic characteristics. These findings support the peripheral, small-signal gain reduction (via proprioceptive tension control) hypothesis. Current linear plant models, limited to normal steady-state muscle tension levels, cannot explain the effects of the tenotomy.
Collapse
Affiliation(s)
- Z Wang
- Daroff-Dell'Osso Ocular Motility Laboratory, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, USA
| | | | | | | | | |
Collapse
|
35
|
Büttner-Ennever JA, Konakci KZ, Blumer R. Sensory control of extraocular muscles. PROGRESS IN BRAIN RESEARCH 2006; 151:81-93. [PMID: 16221586 DOI: 10.1016/s0079-6123(05)51003-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The role of sensory receptors in eye muscles is not well understood, but there is physiological and clinical evidence for the presence of proprioceptive signals in many areas of the central nervous system. It is unclear which structures generate these sensory signals, and which central neural pathways are involved. Three different types of receptors are associated with eye muscles: (1) muscle spindles, (2) palisade endings, and (3) Golgi tendon organs, but their occurrence varies wildly between species. A review of their organization shows that each receptor is mainly confined to a morphologically separate layer of the eye muscle. The palisade endings - which are unique to eye muscles, are associated with the global layer; and they have been found in all mammals studied so far. Their function is unknown. The muscle spindles, if they are present in a species, lie in the orbital layer, or at its junction to the global layer. Golgi tendon organs appear to be unique to artiodactyls (i.e., sheep and goats, etc.); they lie in an outer distal marginal layer of the eye muscle, called the "peripheral patch layer" in sheep. The specific association between palisade endings and the multiply innervated type of muscle fibers of the global layer has led to the hypothesis that together they may act as a sensory receptor, and provide a source of central proprioceptive signals. But other interpretations of the morphological evidence do not support this role.
Collapse
Affiliation(s)
- J A Büttner-Ennever
- Institute of Anatomy, Ludwig-Maximilian University of Munich, Pettenkoferstrasse 11, D-80336 Munich, Germany.
| | | | | |
Collapse
|
36
|
Sylvester R, Rees G. Extraretinal saccadic signals in human LGN and early retinotopic cortex. Neuroimage 2005; 30:214-9. [PMID: 16226468 DOI: 10.1016/j.neuroimage.2005.09.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Revised: 08/31/2005] [Accepted: 09/13/2005] [Indexed: 10/25/2022] Open
Abstract
In the human LGN and V1, saccades in darkness lead to enhanced activity while saccades made during strong visual stimulation suppress activity [Sylvester, R., Haynes, J.D., and Rees, G., 2005. Saccades differentially modulate human LGN and V1 responses in the presence and absence of visual stimulation. Curr. Biol. 15, 37-41]. Here, we explored this differential modulation further using graded changes in the strength of visual stimulation by changing the mean luminance of a flickering visual stimulus. We replicate the finding of differential modulation of activity in human LGN and V1, and show that this relationship also holds in retinotopic areas V2 and V3. Suppression of visually evoked activity during saccades was detectable during strong visual stimulation, but not during weaker stimulation. This suggests that the activation of visual cortex by saccades in darkness represents a signal that persists irrespective of the state of visual stimulation, masking suppressive effects of saccades when visual stimulation is weak. Such a signal may represent a motor signal in a sensory area. We discuss the possible role of oculomotor corollary discharge in changes in visual perception that occur peri-saccadically, which contribute to the successful negation of the disruptive effects of saccades on our seamless visual experience of the world.
Collapse
Affiliation(s)
- Richard Sylvester
- Wellcome Department of Imaging Neuroscience, Institute of Neurology, University College London, 12 Queen Square, London WC1N 3BG, UK.
| | | |
Collapse
|
37
|
Eberhorn AC, Horn AKE, Eberhorn N, Fischer P, Boergen KP, Büttner-Ennever JA. Palisade endings in extraocular eye muscles revealed by SNAP-25 immunoreactivity. J Anat 2005; 206:307-15. [PMID: 15733303 PMCID: PMC1571482 DOI: 10.1111/j.1469-7580.2005.00378.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/17/2004] [Indexed: 11/27/2022] Open
Abstract
Palisade endings form a cuff of nerve terminals around the tip of muscle fibres. They are found only in extraocular muscles, but no definite evidence for their role in eye movements has been established. Palisade endings have been reported in all species so far investigated except the rat. In this study we demonstrate that antibodies against SNAP-25, the synaptosomal associated protein of 25 kDa, reliably visualize the complete motor, sensory and autonomic innervation of the extraocular muscles in human, monkey and rat. The SNAP-25 antibody can be combined with other immunofluorescence procedures, and is used here to study properties of palisade endings. With SNAP-25 immunolabelling putative palisade endings are identified in the rat for the first time. They are not well branched, but fulfil several criteria of palisade endings, being associated with non-twitch fibres as shown by double labelling with 'myosin heavy chain slow-twitch' antibodies. The putative palisade endings of the rat lack alpha-bungarotoxin binding, which implies that these synapses are sensory. If palisade endings are sensory then they could function as an eye muscle proprioceptor. They seem to be a general feature of all vertebrate eye muscles, unlike the other two extraocular proprioceptors, muscle spindles and Golgi tendon organs, the presence of which varies widely between species.
Collapse
|
38
|
Abstract
Eye muscles are unusual in several ways; one is that they have up to three different layers-the inner global layer, the outer orbital layer, and in some species an external marginal layer has been described. In sheep this is called the "peripheral patch layer." Three different types of proprioceptors are found in eye muscles-muscle spindles, Golgi tendon organs, and palisade endings. A survey of the organization of their location leads us to the hypothesis that each receptor is confined to a separate layer of the eye muscle. The palisade endings are associated with the global layer, the muscle spindles lie predominantly in the orbital layer, and the Golgi tendon organs are found only in the peripheral patch layer. This well-organized scheme may help us to understand the proprioceptive system in eye muscles.
Collapse
Affiliation(s)
- J A Büttner-Ennever
- Institute of Anatomy, Ludwig-Maximilians University of Munich, 80336 Munich, Germany.
| | | | | |
Collapse
|
39
|
Büttner-Ennever JA, Horn AKE. The neuroanatomical basis of oculomotor disorders: the dual motor control of extraocular muscles and its possible role in proprioception. Curr Opin Neurol 2002; 15:35-43. [PMID: 11796949 DOI: 10.1097/00019052-200202000-00007] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Current investigations show that two separate sets of motoneurons control the extraocular eye muscles, and that is there is a dual final common pathway. We propose that one set of motoneurons are the major source of tension generating eye movements, whereas the other may participate in a proprioceptive system concerned more with the exact alignment and stabilization of the eyes. In this article we discuss the structures that may participate in the proprioceptive circuits; and consider several recent publications in the light of this sensory feedback hypothesis, emphasizing the relevance to eye movement disorders.
Collapse
|