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Gutiérrez-Ibáñez C, Wylie DR, Altshuler DL. From the eye to the wing: neural circuits for transforming optic flow into motor output in avian flight. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2023; 209:839-854. [PMID: 37542566 DOI: 10.1007/s00359-023-01663-5] [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: 05/22/2023] [Revised: 07/21/2023] [Accepted: 07/25/2023] [Indexed: 08/07/2023]
Abstract
Avian flight is guided by optic flow-the movement across the retina of images of surfaces and edges in the environment due to self-motion. In all vertebrates, there is a short pathway for optic flow information to reach pre-motor areas: retinal-recipient regions in the midbrain encode optic flow, which is then sent to the cerebellum. One well-known role for optic flow pathways to the cerebellum is the control of stabilizing eye movements (the optokinetic response). However, the role of this pathway in controlling locomotion is less well understood. Electrophysiological and tract tracing studies are revealing the functional connectivity of a more elaborate circuit through the avian cerebellum, which integrates optic flow with other sensory signals. Here we review the research supporting this framework and identify the cerebellar output centres, the lateral (CbL) and medial (CbM) cerebellar nuclei, as two key nodes with potentially distinct roles in flight control. The CbM receives bilateral optic flow information and projects to sites in the brainstem that suggest a primary role for flight control over time, such as during forward flight. The CbL receives monocular optic flow and other types of visual information. This site provides feedback to sensory areas throughout the brain and has a strong projection the nucleus ruber, which is known to have a dominant role in forelimb muscle control. This arrangement suggests primary roles for the CbL in the control of wing morphing and for rapid maneuvers.
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Affiliation(s)
| | - Douglas R Wylie
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada.
| | - Douglas L Altshuler
- Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
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2
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Rodriques SG, Stickels RR, Goeva A, Martin CA, Murray E, Vanderburg CR, Welch J, Chen LM, Chen F, Macosko EZ. Slide-seq: A scalable technology for measuring genome-wide expression at high spatial resolution. Science 2019; 363:1463-1467. [PMID: 30923225 DOI: 10.1126/science.aaw1219] [Citation(s) in RCA: 1129] [Impact Index Per Article: 225.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 02/28/2019] [Indexed: 12/24/2022]
Abstract
Spatial positions of cells in tissues strongly influence function, yet a high-throughput, genome-wide readout of gene expression with cellular resolution is lacking. We developed Slide-seq, a method for transferring RNA from tissue sections onto a surface covered in DNA-barcoded beads with known positions, allowing the locations of the RNA to be inferred by sequencing. Using Slide-seq, we localized cell types identified by single-cell RNA sequencing datasets within the cerebellum and hippocampus, characterized spatial gene expression patterns in the Purkinje layer of mouse cerebellum, and defined the temporal evolution of cell type-specific responses in a mouse model of traumatic brain injury. These studies highlight how Slide-seq provides a scalable method for obtaining spatially resolved gene expression data at resolutions comparable to the sizes of individual cells.
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Affiliation(s)
- Samuel G Rodriques
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,MIT Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Robert R Stickels
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.,Graduate School of Arts and Sciences, Harvard University, Cambridge, MA 02138, USA.,Division of Medical Science, Harvard Medical School, Boston, MA 02115, USA
| | | | - Carly A Martin
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Evan Murray
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | | | - Joshua Welch
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Linlin M Chen
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Fei Chen
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
| | - Evan Z Macosko
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA. .,Department of Psychiatry, Massachusetts General Hospital, Boston, MA 02114, USA
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3
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Apps R, Hawkes R, Aoki S, Bengtsson F, Brown AM, Chen G, Ebner TJ, Isope P, Jörntell H, Lackey EP, Lawrenson C, Lumb B, Schonewille M, Sillitoe RV, Spaeth L, Sugihara I, Valera A, Voogd J, Wylie DR, Ruigrok TJH. Cerebellar Modules and Their Role as Operational Cerebellar Processing Units: A Consensus paper [corrected]. CEREBELLUM (LONDON, ENGLAND) 2018; 17:654-682. [PMID: 29876802 PMCID: PMC6132822 DOI: 10.1007/s12311-018-0952-3] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The compartmentalization of the cerebellum into modules is often used to discuss its function. What, exactly, can be considered a module, how do they operate, can they be subdivided and do they act individually or in concert are only some of the key questions discussed in this consensus paper. Experts studying cerebellar compartmentalization give their insights on the structure and function of cerebellar modules, with the aim of providing an up-to-date review of the extensive literature on this subject. Starting with an historical perspective indicating that the basis of the modular organization is formed by matching olivocorticonuclear connectivity, this is followed by consideration of anatomical and chemical modular boundaries, revealing a relation between anatomical, chemical, and physiological borders. In addition, the question is asked what the smallest operational unit of the cerebellum might be. Furthermore, it has become clear that chemical diversity of Purkinje cells also results in diversity of information processing between cerebellar modules. An additional important consideration is the relation between modular compartmentalization and the organization of the mossy fiber system, resulting in the concept of modular plasticity. Finally, examination of cerebellar output patterns suggesting cooperation between modules and recent work on modular aspects of emotional behavior are discussed. Despite the general consensus that the cerebellum has a modular organization, many questions remain. The authors hope that this joint review will inspire future cerebellar research so that we are better able to understand how this brain structure makes its vital contribution to behavior in its most general form.
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Affiliation(s)
- Richard Apps
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Richard Hawkes
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Sho Aoki
- Neurobiology Research Unit, Okinawa Institute of Science and Technology, Onna, Japan
- Department of Neuroscience, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Fredrik Bengtsson
- Department of Experimental Medical Sciences, Lund University, Lund, Sweden
| | - Amanda M. Brown
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX USA
| | - Gang Chen
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
| | - Timothy J. Ebner
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
| | - Philippe Isope
- Institut des Neurosciences Cellulaires et Intégratives, CNRS, Université de Strasbourg, Strasbourg, France
| | - Henrik Jörntell
- Department of Experimental Medical Sciences, Lund University, Lund, Sweden
| | - Elizabeth P. Lackey
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX USA
| | - Charlotte Lawrenson
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Bridget Lumb
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Martijn Schonewille
- Department of Neuroscience, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Roy V. Sillitoe
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX USA
| | - Ludovic Spaeth
- Institut des Neurosciences Cellulaires et Intégratives, CNRS, Université de Strasbourg, Strasbourg, France
| | - Izumi Sugihara
- Department of Systems Neurophysiology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Antoine Valera
- Institut des Neurosciences Cellulaires et Intégratives, CNRS, Université de Strasbourg, Strasbourg, France
| | - Jan Voogd
- Department of Neuroscience, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Douglas R. Wylie
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB Canada
| | - Tom J. H. Ruigrok
- Department of Neuroscience, Erasmus MC Rotterdam, Rotterdam, the Netherlands
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Long RM, Pakan JMP, Graham DJ, Hurd PL, Gutierrez-Ibañez C, Wylie DR. Modulation of complex spike activity differs between zebrin-positive and -negative Purkinje cells in the pigeon cerebellum. J Neurophysiol 2018; 120:250-262. [PMID: 29589816 DOI: 10.1152/jn.00797.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The cerebellum is organized into parasagittal zones defined by its climbing and mossy fiber inputs, efferent projections, and Purkinje cell (PC) response properties. Additionally, parasagittal stripes can be visualized with molecular markers, such as heterogeneous expression of the isoenzyme zebrin II (ZII), where sagittal stripes of high ZII expression (ZII+) are interdigitated with stripes of low ZII expression (ZII-). In the pigeon vestibulocerebellum, a ZII+/- stripe pair represents a functional unit, insofar as both ZII+ and ZII- PCs within a stripe pair respond best to the same pattern of optic flow. In the present study, we attempted to determine whether there were any differences in the responses between ZII+ and ZII- PCs within a functional unit in response to optic flow stimuli. In pigeons of either sex, we recorded complex spike activity (CSA) from PCs in response to optic flow, marked recording sites with a fluorescent tracer, and determined the ZII identity of recorded PCs by immunohistochemistry. We found that CSA of ZII+ PCs showed a greater depth of modulation in response to the preferred optic flow pattern compared with ZII- PCs. We suggest that these differences in the depth of modulation to optic flow stimuli are due to differences in the connectivity of ZII+ and ZII- PCs within a functional unit. Specifically, ZII+ PCs project to areas of the vestibular nuclei that provide inhibitory feedback to the inferior olive, whereas ZII- PCs do not. NEW & NOTEWORTHY Although the cerebellum appears to be a uniform structure, Purkinje cells (PCs) are heterogeneous and can be categorized on the basis of the expression of molecular markers. These phenotypes are conserved across species, but the significance is undetermined. PCs in the vestibulocerebellum encode optic flow resulting from self-motion, and those that express the molecular marker zebrin II (ZII+) exhibit more sensitivity to optic flow than those that do not express zebrin II (ZII-).
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Affiliation(s)
- Rebecca M Long
- Neuroscience and Mental Health Institute, University of Alberta , Edmonton, Alberta , Canada
| | - Janelle M P Pakan
- German Center for Neurodegenerative Diseases (DZNE) , Magdeburg , Germany.,Institute for Cognitive Neurology (IKND), Medical Faculty, Otto von Guericke University Magdeburg , Magdeburg , Germany
| | | | - Peter L Hurd
- Neuroscience and Mental Health Institute, University of Alberta , Edmonton, Alberta , Canada
| | | | - Douglas R Wylie
- Neuroscience and Mental Health Institute, University of Alberta , Edmonton, Alberta , Canada
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Wylie DR, Gutiérrez-Ibáñez C, Corfield JR, Craciun I, Graham DJ, Hurd PL. Inferior olivary projection to the zebrin II stripes in lobule IXcd of the pigeon flocculus: A retrograde tracing study. J Comp Neurol 2017. [PMID: 28649766 DOI: 10.1002/cne.24270] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Zebrin II (ZII; a.k.a. aldolase C) is expressed heterogeneously in Purkinje cells (PCs) such that there are sagittal stripes of high expression (ZII+) interdigitated with stripes of little or no expression (ZII-). The pigeon flocculus receives visual-optokinetic information and is important for generating compensatory eye movements. It consists of 4 sagittal zones based on PC complex spike activity (CSA) in response to rotational optokinetic stimuli. There are two zones where CSA responds best to rotation about the vertical axis (VA), interdigitated with two zones where CSA responds best to rotation about an horizontal axis (HA). These optokinetic zones relate to the ZII stripes in folium IXcd of the flocculus, such that an optokinetic zone spans a ZII+/- pair: the HA zones span the P5+/- and P7+/- ZII stripe pairs, whereas the VA zones correspond to ZII stripe pairs P4+/- and P6+/-. In the present study, we used fluorescent retrograde tracing to determine the olivary inputs to the ZII+ and ZII- stripes within the functional pairs. We found that separate but adjacent areas of the medial column of the inferior olive (mcIO) project to the ZII+ and ZII- stripes within each of the functional pairs. Thus, although a ZII+/- stripe pair represents a functional unit in the pigeon flocculus insofar as the CSA of all PCs in the stripe pair encodes similar sensory information, the olivary inputs to the ZII+ and ZII- stripes arise from different, although adjacent, regions of the mcIO.
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Affiliation(s)
- Douglas R Wylie
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | | | - Jeremy R Corfield
- Department of Biological Sciences, Salisbury University, Salisbury, Maryland
| | - Iulia Craciun
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - David J Graham
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - Peter L Hurd
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
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6
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Aspden JW, Armstrong CL, Gutierrez-Ibanez CI, Hawkes R, Iwaniuk AN, Kohl T, Graham DJ, Wylie DR. Zebrin II / aldolase C expression in the cerebellum of the western diamondback rattlesnake (Crotalus atrox). PLoS One 2015; 10:e0117539. [PMID: 25692946 PMCID: PMC4334253 DOI: 10.1371/journal.pone.0117539] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 12/27/2014] [Indexed: 11/19/2022] Open
Abstract
Aldolase C, also known as Zebrin II (ZII), is a glycolytic enzyme that is expressed in cerebellar Purkinje cells of the vertebrate cerebellum. In both mammals and birds, ZII is expressed heterogeneously, such that there are sagittal stripes of Purkinje cells with high ZII expression (ZII+), alternating with stripes of Purkinje cells with little or no expression (ZII-). The patterns of ZII+ and ZII- stripes in the cerebellum of birds and mammals are strikingly similar, suggesting that it may have first evolved in the stem reptiles. In this study, we examined the expression of ZII in the cerebellum of the western diamondback rattlesnake (Crotalus atrox). In contrast to birds and mammals, the cerebellum of the rattlesnake is much smaller and simpler, consisting of a small, unfoliated dome of cells. A pattern of alternating ZII+ and ZII- sagittal stripes cells was not observed: rather all Purkinje cells were ZII+. This suggests that ZII stripes have either been lost in snakes or that they evolved convergently in birds and mammals.
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Affiliation(s)
- Joel W. Aspden
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - Carol L. Armstrong
- Department of Biology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, Alberta, Canada, T3E 6K6
| | - Cristian I. Gutierrez-Ibanez
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
- Lehrstuhl für Zoologie, Technische Universität München, Liesel-Beckmann Straße 4, 85354, Freising-Weihenstephan, Germany
| | - Richard Hawkes
- Department of Cell Biology & Anatomy, Genes and Development Research Group, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada, T2N 4N1
| | - Andrew N. Iwaniuk
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada, T1K 3M4
| | - Tobias Kohl
- Lehrstuhl für Zoologie, Technische Universität München, Liesel-Beckmann Straße 4, 85354, Freising-Weihenstephan, Germany
| | - David J. Graham
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - Douglas R. Wylie
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
- * E-mail:
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7
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Wylie DR. Processing of visual signals related to self-motion in the cerebellum of pigeons. Front Behav Neurosci 2013; 7:4. [PMID: 23408161 PMCID: PMC3569843 DOI: 10.3389/fnbeh.2013.00004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Accepted: 01/18/2013] [Indexed: 01/07/2023] Open
Abstract
In this paper I describe the key features of optic flow processing in pigeons. Optic flow is the visual motion that occurs across the entire retina as a result of self-motion and is processed by subcortical visual pathways that project to the cerebellum. These pathways originate in two retinal-recipient nuclei, the nucleus of the basal optic root (nBOR) and the nucleus lentiformis mesencephali, which project to the vestibulocerebellum (VbC) (folia IXcd and X), directly as mossy fibers, and indirectly as climbing fibers from the inferior olive. Optic flow information is integrated with vestibular input in the VbC. There is a clear separation of function in the VbC: Purkinje cells in the flocculus process optic flow resulting from self-rotation, whereas Purkinje cells in the uvula/nodulus process optic flow resulting from self-translation. Furthermore, Purkinje cells with particular optic flow preferences are organized topographically into parasagittal "zones." These zones are correlated with expression of the isoenzyme aldolase C, also known as zebrin II (ZII). ZII expression is heterogeneous such that there are parasagittal stripes of Purkinje cells that have high expression (ZII+) alternating with stripes of Purkinje cells with low expression (ZII-). A functional zone spans a ZII± stripe pair. That is, each zone that contains Purkinje cells responsive to a particular pattern of optic flow is subdivided into a strip containing ZII+ Purkinje cells and a strip containing ZII- Purkinje cells. Additionally, there is optic flow input to folia VI-VIII of the cerebellum from lentiformis mesencephali. These folia also receive visual input from the tectofugal system via pontine nuclei. As the tectofugal system is involved in the analysis of local motion, there is integration of optic flow and local motion information in VI-VIII. This part of the cerebellum may be important for moving through a cluttered environment.
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Affiliation(s)
- Douglas R. Wylie
- Centre for Neuroscience and Department of Psychology, University of AlbertaEdmonton, AB, Canada
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8
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Zebrin-immunopositive and -immunonegative stripe pairs represent functional units in the pigeon vestibulocerebellum. J Neurosci 2012; 32:12769-79. [PMID: 22973000 DOI: 10.1523/jneurosci.0197-12.2012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The cerebellum is a site of complex sensorimotor integration and contains up to 80% of the neurons in the brain, yet comparatively little is known about the organization of sensorimotor systems within the cerebellum. It is known that afferent projections and Purkinje cell (PC) response properties are organized into sagittal "zones" in the cerebellum. Moreover, the isoenzyme aldolase C [also known as zebrin II (ZII)] is heterogeneously expressed in cerebellar PCs such that there are sagittal stripes of PCs with high expression (ZII+) interdigitated with stripes of little or no expression (ZII-). In the present study, we show how the ZII stripes in folium IXcd of the vestibulocerebellum in pigeons are related to response properties of PCs. IXcd consists of seven pairs of ZII+/- stripes denoted P1+/- (medial) to P7+/- (lateral). Electrophysiological studies have shown that vestibulocerebellar PCs respond to particular patterns of optic flow resulting from self-motion in three-dimensional space. In our study, we recorded optic flow preferences from PCs in IXcd, marked recording locations with injections of fluorescent tracer, and subsequently immunoreacted coronal sections for ZII. We found that the PCs within a ZII+/- stripe pair all responded best to the same pattern of optic flow. That is, a ZII+/- stripe pair forms a functional unit in the cerebellum. This is the first demonstration that the function of PCs is associated with ZII stripes across the mediolateral extent of an entire folium.
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Wylie DR, Pakan JMP, Huynh H, Graham DJ, Iwaniuk AN. Distribution of zebrin-immunoreactive Purkinje cell terminals in the cerebellar and vestibular nuclei of birds. J Comp Neurol 2012; 520:1532-46. [PMID: 22105608 DOI: 10.1002/cne.22810] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Zebrin II (aldolase C) is expressed in a subset of Purkinje cells in the mammalian and avian cerebella such that there is a characteristic parasagittal organization of zebrin-immunopositive stripes alternating with zebrin-immunonegative stripes. Zebrin is expressed not only in the soma and dendrites of Purkinje cells but also in their axonal terminals. Here we describe the distribution of zebrin immunoreactivity in both the vestibular and the cerebellar nuclei of pigeons (Columba livia) and hummingbirds (Calypte anna, Selasphorus rufus). In the medial cerebellar nucleus, zebrin-positive labeling was particularly heavy in the “shell,” whereas the “core” was zebrin negative. In the lateral cerebellar nucleus, labeling was not as heavy, but a positive shell and negative core were also observed. In the vestibular nuclear complex, zebrin-positive terminal labeling was heavy in the dorsolateral vestibular nucleus and the lateral margin of the superior vestibular nucleus. The central and medial regions of the superior nucleus were generally zebrin negative. Labeling was moderate to heavy in the medial vestibular nucleus, particulary the rostral half of the parvocellular subnucleus. A moderate amount of zebrin-positive labeling was present in the descending vestibular nucleus: this was heaviest laterally, and the central region was generally zebrin negative. Zebrin-positive terminals were also observed in the the cerebellovestibular process, prepositus hypoglossi, and lateral tangential nucleus. We discuss our findings in light of similar studies in rats and with respect to the corticonuclear projections to the cerebellar nuclei and the functional connections of the vestibulocerebellum with the vestibular nuclei.
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Affiliation(s)
- Douglas R Wylie
- University Centre for Neuroscience, Department of Psychology, University of Alberta, Edmonton, Alberta, T6G 2E9 Canada.
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10
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Heterogeneity of parvalbumin expression in the avian cerebellar cortex and comparisons with zebrin II. Neuroscience 2011; 185:73-84. [DOI: 10.1016/j.neuroscience.2011.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 04/05/2011] [Accepted: 04/06/2011] [Indexed: 11/20/2022]
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11
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Marzban H, Chung SH, Pezhouh MK, Feirabend H, Watanabe M, Voogd J, Hawkes R. Antigenic compartmentation of the cerebellar cortex in the chicken (Gallus domesticus). J Comp Neurol 2010; 518:2221-39. [PMID: 20437525 DOI: 10.1002/cne.22328] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The chick is a well-understood developmental model of cerebellar pattern formation,but we know much less about the patterning of the adult chicken cerebellum. Therefore an expression study of two Purkinje cell stripe antigens-zebrin II/aldolase C and phospholipase Cbeta4 (PLCbeta4)-has been carried out in the adult chicken (Gallus domesticus). The mammalian cerebellar cortex is built around transverse expression domains ("transverse zones"), each of which is further subdivided into parasagittally oriented stripes. The results from the adult chicken reveal a similar pattern. Five distinct transverse domains were identified. In the anterior lobe a uniformly zebrin II-immunopositive/PLCbeta4-immunonegative lingular zone (LZ; lobule I) and a striped anterior zone (AZ; lobules II-VIa) were distinguished. A central zone (CZ; approximately lobules VIa-VIIIa,b) and a posterior zone (PZ; approximately lobules VIIIa,b-IXc,d) were distinguished in the posterior lobe. Finally, the nodular zone (NZ; lobule X) is uniformly zebrin II-immunoreactive and is innervated by vestibular mossy fibers. Lobule IXc,d is considered as a transitional region between the PZ and the NZ, because the vestibular mossy fiber projection extends into these lobules and because they receive optokinetic mossy and climbing fiber input. It is proposed that the zebrin II-immunonegative P3- stripe corresponds to the lateral vermal B zone of the mammalian cerebellum and that the border between the avian homologs of the mammalian vermis and hemispheres is located immediately lateral to P3-. Thus, there seem to be transverse zones in chicken that are plausible homologs of those identified in mammals, together with an LZ that is characteristic of birds.
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Affiliation(s)
- Hassan Marzban
- Department of Cell Biology & Anatomy, Genes and Development Research Group, and Hotchkiss Brain Institute, Faculty of Medicine, The University of Calgary, Calgary, Alberta T2N 4N1, Canada
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12
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Relationship between complex and simple spike activity in macaque caudal vermis during three-dimensional vestibular stimulation. J Neurosci 2010; 30:8111-26. [PMID: 20554862 DOI: 10.1523/jneurosci.5779-09.2010] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Lobules 10 and 9 in the caudal posterior vermis [also known as nodulus and uvula (NU)] are thought important for spatial orientation and balance. Here, we characterize complex spike (CS) and simple spike (SS) activity in response to three-dimensional vestibular stimulation. The strongest modulation was seen during translation (CS: 12.8 +/- 1.5, SS: 287.0 +/- 23.2 spikes/s/G, 0.5 Hz). Preferred directions tended to cluster along the cardinal axes (lateral, fore-aft, vertical) for CSs and along the semicircular canal axes for SSs. Most notably, the preferred directions for CS/SS pairs arising from the same Purkinje cells were rarely aligned. During 0.5 Hz pitch/roll tilt, only about a third of CSs had significant modulation. Thus, most CSs correlated best with inertial rather than net linear acceleration. By comparison, all SSs were selective for translation and ignored changes in spatial orientation relative to gravity. Like SSs, tilt modulation of CSs increased at lower frequencies. CSs and SSs had similar response dynamics, responding to linear velocity during translation and angular position during tilt. The most salient finding is that CSs did not always modulate out-of-phase with SSs. The CS/SS phase difference varied broadly among Purkinje cells, yet for each cell it was precisely matched for the otolith-driven and canal-driven components of the response. These findings illustrate a spatiotemporal mismatch between CS/SS pairs and provide the first comprehensive description of the macaque NU, an important step toward understanding how CSs and SSs interact during complex movements and spatial disorientation.
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13
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Pakan JMP, Graham DJ, Wylie DR. Organization of visual mossy fiber projections and zebrin expression in the pigeon vestibulocerebellum. J Comp Neurol 2010; 518:175-98. [PMID: 19937710 DOI: 10.1002/cne.22192] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Extensive research has revealed a fundamental organization of the cerebellum consisting of functional parasagittal zones. This compartmentalization has been well documented with respect to physiology, biochemical markers, and climbing fiber afferents. Less is known about the organization of mossy fiber afferents in general, and more specifically in relation to molecular markers such as zebrin. Zebrin is expressed by Purkinje cells that are distributed as a parasagittal array of immunopositive and immunonegative stripes. We examined the concordance of zebrin expression with visual mossy fiber afferents in the vestibulocerebellum (folium IXcd) of pigeons. Visual afferents project directly to folium IXcd as mossy fibers and indirectly as climbing fibers via the inferior olive. These projections arise from two retinal recipient nuclei: the lentiformis mesencephali (LM) and the nucleus of the basal optic root (nBOR). Although it has been shown that these two nuclei project to folium IXcd, the detailed organization of these projections has not been reported. We injected anterograde tracers into LM and nBOR to investigate the organization of mossy fiber terminals and subsequently related this organization to the zebrin antigenic map. We found a parasagittal organization of mossy fiber terminals in folium IXcd and observed a consistent relationship between mossy fiber organization and zebrin stripes: parasagittal clusters of mossy fiber terminals were concentrated in zebrin-immunopositive regions. We also describe the topography of projections from LM and nBOR to the inferior olive and relate these results to previous studies on the organization of climbing fibers and zebrin expression.
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Affiliation(s)
- Janelle M P Pakan
- Centre for Neuroscience, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
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Congruence of zebrin II expression and functional zones defined by climbing fiber topography in the flocculus. Neuroscience 2008; 157:57-69. [DOI: 10.1016/j.neuroscience.2008.08.062] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 08/21/2008] [Accepted: 08/22/2008] [Indexed: 11/17/2022]
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Pakan JMP, Graham DJ, Iwaniuk AN, Wylie DRW. Differential projections from the vestibular nuclei to the flocculus and uvula-nodulus in pigeons (Columba livia). J Comp Neurol 2008; 508:402-17. [PMID: 18335537 DOI: 10.1002/cne.21623] [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 pigeon vestibulocerebellum is divided into two regions based on the responses of Purkinje cells to optic flow stimuli: the uvula-nodulus responds best to self-translation, and the flocculus responds best to self-rotation. We used retrograde tracing to determine whether the flocculus and uvula-nodulus receive differential mossy fiber input from the vestibular and cerebellar nuclei. From retrograde injections into the both the flocculus and uvula-nodulus, numerous cells were found in the superior vestibular nucleus (VeS), the cerebellovestibular process (pcv), the descending vestibular nucleus (VeD), and the medial vestibular nucleus (VeM). Less labeling was found in the prepositus hypoglossi, the cerebellar nuclei, the dorsolateral vestibular nucleus, and the lateral vestibular nucleus, pars ventralis. In the VeS, the differential input to the flocculus and uvula-nodulus was distinct: cells were localized to the medial and lateral regions, respectively. The same pattern was observed in the VeD, although there was considerable overlap. In the VeM, the majority of cells labeled from the flocculus were in rostral margins on the ipsilateral side, whereas labeling from uvula-nodulus injections was distributed bilaterally throughout the VeM. Finally, from injections in the flocculus but not the uvula-nodulus, moderate labeling was observed in a paramedian area, adjacent to the medial longitudinal fasciculus. In summary, there were clear differences with respect to the projections from the vestibular nuclei to functionally distinct parts of the vestibulocerebellum. Generally speaking, the mossy fibers to the flocculus and uvula-nodulus arise from regions of the vestibular nuclei that receive input from the semicircular canals and otolith organs, respectively.
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Affiliation(s)
- Janelle M P Pakan
- Centre for Neuroscience, University of Alberta, Edmonton, Alberta, Canada T6G 2E9
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Wylie DRW, Pakan JMP, Elliott CA, Graham DJ, Iwaniuk AN. Projections of the nucleus of the basal optic root in pigeons (Columba livia): A comparison of the morphology and distribution of neurons with different efferent projections. Vis Neurosci 2007; 24:691-707. [PMID: 17915041 DOI: 10.1017/s0952523807070599] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Accepted: 07/10/2007] [Indexed: 11/06/2022]
Abstract
The avian nucleus of the basal optic root (nBOR) is a visual structure involved in the optokinetic response. nBOR consists of several morphologically distinct cell types, and in the present study, we sought to determine if these different cell types had differential projections. Using retrograde tracers, we examined the morphology and distribution of nBOR neurons projecting to the vestibulocerebellum (VbC), inferior olive (IO), dorsal thalamus, the pretectal nucleus lentiformis mesencephali (LM), the contralateral nBOR, the oculomotor complex (OMC) and a group of structures along the midline of the mesencephalon. The retrogradely labeled neurons fell into two broad categories: large neurons, most of which were multipolar rather than fusiform and small neurons, which were either fusiform or multipolar. From injections into the IO, LM, contralateral nBOR, and structures along the midline-mesencephalon small nBOR neurons were labeled. Although there were no differences with respect to the size of the labeled neurons from these injections, there were some differences with the respect to the distribution of labeled neurons and the proportion of multipolar vs. fusiform neurons. From injections into the VbC, the large multipolar cells were labeled throughout nBOR. The only other cases in which these large neurons were labeled were contralateral OMC injections. To investigate if single neurons project to multiple targets we used paired injections of red and green fluorescent retrograde tracers into different targets. Double-labeled neurons were never observed indicating that nBOR neurons do not project to multiple targets. We conclude that individual nBOR neurons have unique projections, which may have differential roles in processing optic flow and controlling the optokinetic response.
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Affiliation(s)
- Douglas R W Wylie
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada.
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Pakan JMP, Iwaniuk AN, Wylie DRW, Hawkes R, Marzban H. Purkinje cell compartmentation as revealed by Zebrin II expression in the cerebellar cortex of pigeons (Columba livia). J Comp Neurol 2007; 501:619-30. [PMID: 17278140 DOI: 10.1002/cne.21266] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Purkinje cells in the cerebellum express the antigen zebrin II (aldolase C) in many vertebrates. In mammals, zebrin is expressed in a parasagittal fashion, with alternating immunopositive and immunonegative stripes. Whether a similar pattern is expressed in birds is unknown. Here we present the first investigation into zebrin II expression in a bird: the adult pigeon (Columba livia). Western blotting of pigeon cerebellar homogenates reveals a single polypeptide with an apparent molecular weight of 36 kDa that is indistinguishable from zebrin II in the mouse. Zebrin II expression in the pigeon cerebellum is prominent in Purkinje cells, including their dendrites, somata, axons, and axon terminals. Parasagittal stripes were apparent with bands of Purkinje cells that strongly expressed zebrin II (+ve) alternating with bands that expressed zebrin II weakly or not at all (-ve). The stripes were most prominent in folium IXcd, where there were seven +ve/-ve stripes, bilaterally. In folia VI-IXab, several thin stripes were observed spanning the mediolateral extent of the folia, including three pairs of +ve/-ve stripes that extended across the lateral surface of the cerebellum. In folium VI the zebrin II expression in Purkinje cells was stronger overall, resulting in less apparent stripes. In folia II-V, four distinct +ve/-ve stripes were apparent. Finally, in folia I (lingula) and X (nodulus) all Purkinje cells strongly expressed zebrin II. These data are compared with studies of zebrin II expression in other species, as well as physiological and neuroanatomical studies that address the parasagittal organization of the pigeon cerebellum.
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Affiliation(s)
- Janelle M P Pakan
- University Centre for Neuroscience, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
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Frost BJ, Mouritsen H. The neural mechanisms of long distance animal navigation. Curr Opin Neurobiol 2006; 16:481-8. [PMID: 16839758 DOI: 10.1016/j.conb.2006.06.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2006] [Accepted: 06/28/2006] [Indexed: 11/22/2022]
Abstract
Animal navigation is a complex process involving the integration of many sources of specialized sensory information for navigation in near and far space. Our understanding of the neurobiological underpinnings of near-space navigation is well-developed, whereas the neural mechanisms of long-distance navigation are just beginning to be unraveled. One crucial question for future research is whether the near space concepts of place cells, head direction cells, and maps in the entorhinal cortex scale up to animals navigating over very long distances and whether they are related to the map and compass concepts of long-distance navigation.
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Affiliation(s)
- Barrie J Frost
- Department of Psychology, Queen's University, Kingston, Ontario, K7L 3N6, Canada.
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Winship IR, Wylie DRW. Receptive-field structure of optic flow responsive Purkinje cells in the vestibulocerebellum of pigeons. Vis Neurosci 2006; 23:115-26. [PMID: 16597355 DOI: 10.1017/s0952523806231109] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Accepted: 11/23/2005] [Indexed: 11/06/2022]
Abstract
Neurons sensitive to optic flow patterns have been recorded in the the olivo-vestibulocerebellar pathway and extrastriate visual cortical areas in vertebrates, and in the visual neuropile of invertebrates. The complex spike activity (CSA) of Purkinje cells in the vestibulocerebellum (VbC) responds best to patterns of optic flow that result from either self-rotation or self-translation. Previous studies have suggested that these neurons have a receptive-field (RF) structure that “approximates” the preferred optic flowfield with a “bipartite” organization. Contrasting this, studies in invertebrate species indicate that optic flow sensitive neurons are precisely tuned to their preferred flowfield, such that the local motion sensitivities and local preferred directions within their RFs precisely match the local motion in that region of the preferred flowfield. In this study, CSA in the VbC of pigeons was recorded in response to a set of complex computer-generated optic flow stimuli, similar to those used in previous studies of optic flow neurons in primate extrastriate visual cortex, to test whether the receptive field was of a precise or bipartite organization. We found that these RFs were not precisely tuned to optic flow patterns. Rather, we conclude that these neurons have a bipartite RF structure that approximates the preferred optic flowfield by pooling motion subunits of only a few different direction preferences.
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Affiliation(s)
- Ian R Winship
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
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Pakan JMP, Wylie DRW. Two optic flow pathways from the pretectal nucleus lentiformis mesencephali to the cerebellum in pigeons (Columba livia). J Comp Neurol 2006; 499:732-44. [PMID: 17048227 DOI: 10.1002/cne.21108] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Neurons in the pretectal nucleus lentiformis mesencephali (LM) are involved in the analysis of optic flow. LM provides mossy fiber inputs to folia VI-VIII of the posterior cerebellum and IXcd of the vestibulocerebellum. Previous research has shown that the vestibulocerebellum is involved in visual-vestibular integration supporting gaze stabilization. The function of folia VI-VIII in pigeons is not well understood; however, these folia receive input from a tectopontine system, which is likely involved with analyzing local motion as opposed to optic flow. We sought to determine whether the mossy fiber input from LM to IXcd differs from that to VI-VIII. Fluorescent retrograde tracers were injected into these folia, and the pattern of labeling in LM was observed. Large multipolar neurons were labeled throughout the rostrocaudal extent of LM. There was a clear mediolateral difference: 74.3% of LM neurons projecting to IXcd were located in the lateral subnucleus of LM (LMl), whereas 73.8% of LM neurons projecting to VI-VIII were found in medial LM (LMm). This suggests that the subnuclei of LM have differing roles. In particular, the LMl-IXcd pathway is involved in generating the optokinetic response. We suggest that the pathway from LMm to VI-VIII is integrating optic flow and local motion to support various oculomotor and visuomotor behaviors, including obstacle avoidance during locomotion.
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Affiliation(s)
- Janelle M P Pakan
- Division of Neuroscience, University of Alberta, Edmonton, Alberta, Canada T6G 2E9
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Winship IR, Pakan JMP, Todd KG, Wong-Wylie DR. A comparison of ventral tegmental neurons projecting to optic flow regions of the inferior olive vs. the hippocampal formation. Neuroscience 2006; 141:463-73. [PMID: 16698184 DOI: 10.1016/j.neuroscience.2006.03.057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2005] [Revised: 03/16/2006] [Accepted: 03/23/2006] [Indexed: 11/20/2022]
Abstract
The ventral tegmental area (catecholaminergic group A10) is a midbrain region characterized by concentrated dopaminergic immunoreactivity. Previous studies in pigeons show that the ventral tegmental area provides a robust projection to the hippocampal formation and to the medial column of the inferior olive. However, the distribution, morphology, and neurochemical content of the neurons that constitute these projections have not been resolved. In this study, we used a combination of retrograde tracing techniques and immunofluorohistochemistry to address these issues. Retrograde tracers were used to demonstrate that the distribution of ventral tegmental area neurons projecting to the hippocampus and the inferior olive overlap in the caudo-ventral ventral tegmental area. The hippocampus- and inferior olive-projecting ventral tegmental area neurons could not be distinguished based on morphology: most neurons had small- to medium-sized multipolar or fusiform soma. Double-labeling with fluorescent retrograde tracers revealed that the hippocampus- and medial column of the inferior olive-projecting neurons were found intermingled in the ventral tegmental area, but no cells were double labeled; i.e. individual ventral tegmental area neurons do not project to both the hippocampal formation and medial column of the inferior olive. Finally, we found that a minority (8.2%) of ventral tegmental area neurons providing input to the hippocampus were tyrosine hydroxylase-immunoreactive, whereas none of the inferior olive-projecting neurons were tyrosine hydroxylase positive. Combined, our findings show that the projections to the hippocampus and olivocerebellar pathway arise from intermixed subpopulations of ventral tegmental area neurons with indistinguishable morphology but only the hippocampal projection involves dopaminergic neurons. We suggest that equivalent projections from the ventral tegmental area to the hippocampal formation and inferior olive exist in mammals and discuss their potential role in the processing of optic flow and the analysis of self-motion.
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Affiliation(s)
- I R Winship
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
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Abstract
The anatomical, physiological, and behavioral evidence for the involvement of three regions of the cerebellum in oculomotor behavior is reviewed here: (1) the oculomotor vermis and paravermis of lobules V, IV, and VII; (2) the uvula and nodulus; (3) flocculus and ventral paraflocculus. No region of the cerebellum controls eye movements exclusively, but each receives sensory information relevant for the control of multiple systems. An analysis of the microcircuitry suggests how sagittal climbing fiber zones bring visual information to the oculomotor vermis; convey vestibular information to the uvula and nodulus, while optokinetic space is represented in the flocculus. The mossy fiber projections are more heterogeneous. The importance of the inferior olive in modulating Purkinje cell responses is discussed.
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Affiliation(s)
- Jan Voogd
- Department of Neuroscience, Erasmus Medical Center Rotterdam, Box 1738, 3000 DR Rotterdam, The Netherlands.
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Iwaniuk AN, Hurd PL, Wylie DRW. The comparative morphology of the cerebellum in caprimulgiform birds: evolutionary and functional implications. BRAIN, BEHAVIOR AND EVOLUTION 2005; 67:53-68. [PMID: 16244465 DOI: 10.1159/000089120] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Accepted: 03/12/2005] [Indexed: 11/19/2022]
Abstract
Interspecific variation in the structure of the avian cerebellum is poorly understood. We present the first comparison of cerebellar morphology within the avian order Caprimulgiformes. Using a range of qualitative descriptions and quantitative measurements of cerebellar morphology we compared caprimulgiform birds with hummingbirds and swifts (Apodiformes) and owls (Strigiformes), two groups that are putative sister taxa to the Caprimulgiformes. Our results demonstrate that the owlet-nightjars (Aegothelidae), nightjars (Caprimulgidae) and potoos (Nyctibiidae) are more similar to apodiforms than they are to other taxa. All of these species have a reduced anterior lobe characterized by particularly small folia II and III and a relatively large posterior lobe. The frogmouths (Podargidae) possess a markedly different cerebellum that is more similar to that of owls than any of the caprimulgiform or apodiform birds. The monotypic oilbird (Steatornis caripensis, Steatornithidae) possesses a cerebellum with some nightjar-like features and some owl-like features, but overall it too resembles an owl more than a nightjar. This cerebellar diversity within the order Caprimulgiformes has significant implications for understanding the evolutionary relationships within the order, how the avian cerebellum has evolved and whether interspecific differences in cerebellar morphology reflect behavior.
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Affiliation(s)
- Andrew N Iwaniuk
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada.
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