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  • Paul J. May, PhD

     may, paul.jpg

    Professor, Neurobiology and Anatomical Sciences
    Assistant Professor, Ophthalmology
    Assistant Professor, Neurology
    Associate Chair for Research, Neurobiology and Anatomical Sciences
    Office: R720
    Phone: (601) 984-1662
    Lab: R717; Phone: (601) 984-2646
    Fax: (601) 984-1655
    E-mail: pmay@umc.edu


    • AB - Brown University, Providence, R.I. 1976, Biology and English Literature
    • PhD - Duke University, Durham, N.C. 1983, Anatomy. Dissertation title: "The Motor Colliculus: Its Morphology and Inputs." Thesis adviser: William C. Hall, PhD
    • Postdoctoral Fellow - Department of Physiology & Biophysics, New York University Medical Center, New York, NY, 1983-86. Mentor: Robert Baker, PhD

    Teaching responsibilities

    • Course Director for Medical Histology & Cell Biology
    • Lecturer for Dental Histology and Developmental Biology
    • Lecturer for Neurobiology
    • Lecture for Foundations of Neuroscience

    Research interests

    • Trigeminal pathways
    • Circuitry of eyelid, pupil and lens reflexes
    • Proprioceptive control of eye movements
    • Visual gaze control

    Research program

    may 12.jpgThe general experimental theme of the laboratory is the study of gaze control utilizing anatomical and, in some cases, physiological methods. Dual input-output labeling techniques have been pioneered in this laboratory to support this investigation on the light and electron microscopic level. Students can take advantage of opportunities to learn: neuroanatomical tracer techniques, immunohistochemistry, sterile surgery, electron microscopy and post-embedding immunohistochemical localization. There are ongoing investigations in a number of areas concerning gaze control:

    • Control of movements of the eyes and head by the superior colliculus. Both the input-output relationships of superior colliculus and the relationship of collicular projections to cell populations in the horizontal and vertical gaze centers are being studied. The emphasis is on determining the morphology and laminar location of relevant collicular neurons and their synaptic relationships, both within the superior colliculus and between collicular axons and target neurons
    • Neuronal circuitry controlling the lens and pupil is being investigated. Neuroanatomical tracers have been used to determine the circuits controlling the pupillary light reflex, and are being applied to identify the circuits controlling the near reflex components, i.e., ciliary muscle for lens accommodation, medial rectus muscle for vergence and sphincter pupillae muscle for pupillary constriction.
    • Determination of premotor circuitry underlying the blink reflex. The act of blinking is a simple reflex activity that has become important in various learning paradigms and has clinical relevance as well. However, the circuits that support this reflex are poorly understood. This investigation utilizes dual labeling of inputs and outputs to define blink circuits at the light and electron microscopic level.may 13.jpg

    Current funding

    • NEI RO1 Grant (EY014263)
      Midbrain Circuitry for Neuronal Control of Gaze. Co-PI, 2015-19
    • NIDCD R01 Grant (DC014930)
      Neural Mechanisms of Active Gaze Stabilization (AGS) in Monkeys. Co-PI, 2015-19
    • NEI R01 Grant (R01EY019963)
      An In Vitro Model of Saccadic Eye Movement Choice. Co-I, 2016-21

    Selected publications

    A complete publication list can be accessed through MyBibliography at NCBI. 

    Reviews, chapters and books

    • Hall, William C. and Paul J. May. (1983) The anatomical basis for sensorimotor transformations in the superior colliculus. In: Contributions to Sensory Physiology, edited by W.D. Neff, Academic Press, New York, Vol. 8: 1-40.
    • May, Paul J, William C. Hall, John D. Porter and Sharleen T. Sakai. (1993) The comparative anatomy of nigral and cerebellar control over tectally initiated orienting movements. In: Role of the Cerebellum and Basal Ganglia in Voluntary Movement, Edited by N. Mano, I. Hamada and M.R. DeLong, Elsevier, Amsterdam, pp. 221-231. 
    • May, Paul J. and Susan Warren. (2000) Brainstem Pathways Controlling Lid Closure. In: Benign Essential Blepharospasm Newsletter. Vol. 19, No. 2, pp. 3-4. 
    • May, Paul J., Robert G. Baker and Bingzhong Chen (2002) The Eyelid Levator Muscle: Servant of Two Masters. In: Movement Disorders 17, pp.S4-S7. 
    • May, Paul J., Susan Warren, Bingzhong Chen, Frances J.R. Richmond and Etienne Olivier (2002) Midbrain Reticular Formation Circuitry Subserving Gaze in the Cat. In: Neurobiology of Eye Movements. Annals of the New York Academy of Sciences Vol. 956, Edited by H.J. Kaminsky and R.J. Leigh. New York, pp.405-408. 
    • The Mammalian Superior Colliculus: Laminar Structure and Connections. (2006) In: Neuroanatomy of the Oculomotor System. Ed: Jean Buttner-Ennever, Progress in Brain Research, Vol. 151, Elsevier, Amsterdam, pp. 321-78.  
    • May, Paul J., Wensi Sun and Jonathan T. Erichesen (2008) Defining the Pupillary Component of the Perioculomotor Preganglionic Population within a Unitary Primate Edinger-Westphal Nucleus. In: Using Eye Movements as an Experimental Probe of Brain Function, Edited by C. Kennard & R.J. Leigh, Progress in Brain Research Vol. 171, pp. 97-106
    • May, Paul J. (2012) Superior Colliculus. In: The Encyclopedia of Neurological Sciences. Edited by M.J. Aminoff and R.B. Daroff, Academic Press.   
    • May, Paul J. and James J. Corbett. (2013) Visual Motor Systems. In: Fundamental Neuroscience, 4th Edition, Textbook edited by D.E. Haines, Churchill Livingstone, New York, pp. 454-472.
    • Mihailoff, Gregory A., Duane E. Haines and Paul J. May. (2013) The Midbrain. In: Fundamental Neuroscience, 4th Edition, Textbook edited by D.E. Haines, Churchill Livingstone, New York, pp. 196-208.  
    • Barnerssoi, Miriam and Paul J. May. (2015) Postembedding Immunohistochemistry for Inhibitory Neurotransmitters in Conjunction with Neuroanatomical Tracers. In: Transmission Electron Microscopy Methods for Understanding the Brain, Edited by E.J. Van Boekstaele, Springer (In Press). 

    Peer-reviewed papers

    • May, Paul J. and William C. Hall. (1984) Relationships between the nigrotectal pathway and the cells of origin of the predorsal bundle. Journal of Comparative Neurology 226: 357-376.
    • May, Paul J., Harriet Baker, Pierre-Paul Vidal, Robert F. Spencer and Robert Baker. (1987) Morphology and distribution of serotoninergic and oculomotor internuclear neurons in the cat midbrain. Journal of Comparative Neurology 266: 150-170.
    • May, Paul J., Pierre-Paul Vidal and Robert Baker. (1990) Synaptic organization of the tectal-facial pathways in the cat. II. Synaptic potentials following midbrain tegmentum stimulation. Journal of Neurophysiology 64: 381-402.
    • May, Paul J., Rosi Hartwich-Young, Jon Nelson, David L. Sparks and John D. Porter. (1990) Cerebellotectal pathways in the macaque: Implications for collicular generation of saccades. Neuroscience 36: 305-324.
    • May, Paul J., John D. Porter and Paul Gamlin. (1992) Interconnections between the cerebellum and midbrain near response regions. Journal of Comparative Neurology 315: 98-116.
    • May, Paul J. and John D. Porter. (1992) The laminar distribution of macaque tectobulbar and tectospinal neurons. Visual Neuroscience 8: 257-76.
    • May, Paul J. and Susan Warren. (1993) Ultrastructure of the macaque ciliary ganglion. Journal of Neurocytology 22: 1073-1095.
    • May, Paul J., Wensi Sun and William C. Hall. (1997) Reciprocal connections between the zona incerta and the pretectum and superior colliculus of the cat. Neuroscience 77: 1091-1114.
    • May, Paul J. and John D. Porter. (1998) The distribution of primary afferent terminals from the eyelids of macaque monkeys. Experimental Brain Research 123: 368-381.
    • Chen, Bingzhong and Paul J. May. (2000) The feedback circuit connecting the superior colliculus and central mesencephalic reticular formation: A direct morphological demonstration. Experimental Brain Research 131: 10-21.
    • Erichsen, Jonathan T. and Paul J. May. (2002) The pupillary and ciliary components of the cat Edinger-Westphal nucleus: A trans-synaptic transport Investigation. Visual Neuroscience 19: 15-29.
    • Chen, Bingzhong and Paul J. May. (2002) Premotor control of eyelid movements in conjunction with vertical saccades in the cat: The rostral interstitial nucleus of the medial longitudinal fasciculus. Journal of Comparative Neurology 450: 183-202.
    • May, Paul J., Anton J. Reiner and Andrey E. Ryabinin (2008) Comparison of the distributions of urocortin containing and cholinergic neurons in the perioculomotor midbrain of the cat and macaque. Journal of Comparative Neurology 507: 1300-1316.
    • May, Paul J., John G. McHaffie, Terrence R. Stanford, Huai Jiang, M. Gabriela Costello, Veronique Coizet, Lauren M. Hayes, Suzanne N. Haber and Peter Redgrave (2009) Tectonigral projections in the primate: A pathway for pre-attentive sensory input to midbrain dopaminergic neurons. European Journal of Neuroscience 29: 575-587.
    • Perkins, Eddie, Susan Warren and Paul J. May (2009) The mesencephalic reticular formation as a conduit for primate collicular gaze control: Tectal inputs to neurons targeting the spinal cord and medulla. Anatomical Record 292: 1162-1181.
    • Wang, Niping, Susan Warren and Paul J. May (2010) The macaque midbrain reticular formation sends side-specific feedback to the superior colliculus. Experimental Brain Research 201: 701-717.
    • Zimmerman, Lars, Paul. J. May, Angel M. Pastor, Johannes Streicher, Roland Blumer (2011) Evidence that the extraocular motor nuclei innervate monkey palisade endings. Neuroscience Letters 489: 89-93.
    • Kozicz, Tamás, Jackson C. Bittencourt, Paul J. May, Anton Reiner, Paul D. R. Gamlin, Miklós Palkovits, Anja K.E. Horn, Claudio A. B. Toledo and Andrey Ryabinin (2011) The Edinger-Westphal nucleus: A historical, structural and functional perspective of a dichotomous terminology. Journal of Comparative Neurology 519: 1413-1434.
    • May, Paul J., Pierre-Paul Vidal, Harriet Baker and Robert Baker (2012) Physiological and anatomical evidence for an inhibitory trigemino-oculomotor pathway in the cat.  Journal of Comparative Neurology 520: 2218-2240.
    • Wang, Niping, Eddie Perkins, Lan Zhou, Susan Warren and Paul J. May (2013) Anatomical evidence that the superior colliculus controls saccades through central mesencephalic reticular formation gating of omnipause neuron activity. Journal of Neuroscience 33: 16285- 16296.
    • Erichsen, Jonathan T., Nicholas Wright and Paul J. May. (2013) The morphology and ultrastructure of medial rectus subgroup motoneurons in the macaque monkey. Journal of Comparative Neurology 522: 626-641.
    • Sun, Wensi and Paul J. May (2014) Central pupillary light reflex circuits in the cat: The olivary pretectal nucleus. Journal of Comparative Neurology 522: 3960-77.
    • Sun, Wensi and Paul J. May (2014) Central pupillary light reflex circuits in the cat: Morphology, ultrastructure and inputs of preganglionic motoneurons. Journal of Comparative Neurology 522: 3978-4002.
    • Bohlen, Martin O., Susan Warren and Paul J. May. (2015) A central mesencephalic reticular formation projection to the supraoculomotor area in macaque monkeys. Brain Structure & Function (Currently an EPub).
    • May, Paul J, Susan Warren, Martin O. Bohlen, Miriam Barnerssoi, and Anja K.E. Horn, (2015) The central mesencephalic reticular formation projection to the Edinger-Westphal nucleus. Brain Structure and Function (Submitted).

    Recent abstracts

    • Warren, S. and May, P.J. (2010) Targets of the tectal projection to the oculomotor nucleus. Soc. Neurosci. Abst. 36: 894.10.
    • May, P.J., Horn, A.K.E. and Mustari M.J. (2010) Pretectal input to macaque C-group medial rectus motoneurons. Soc. Neurosci. Abst. 36: 894.9.
    • May, P.J., A.K.E. Horn, M.J. Mustari, S. Warren. (2011) Central mesencephalic reticular formation projections onto oculomotor motoneurons.Soc. Neurosci. Abst. 37: 699.01
    • Warren, S., A.K.E. Horn, M.O. Bohlen, P.J. May. (2011) Does the central mesencephalic reticular formation project to vertical gaze motoneurons? Soc. Neurosci. Abst. 37: 699.05
    • Horn. A.K.E., M.E. Bohlen, S. Warren, P.J. May (2012) Evidence for the central mesencephalic reticular formation playing a role in the near triad. Soc. Neurosci. Abst. 38: 371.02
    • Bohlen, M.O., S. Warren, M. Mustari, P.J. May. (2012) Are there subgroups of rectus motoneurons related to fiber type and layer in the cat? Soc. Neurosci. Abst. 38: 373.12
    • Horn. A.K.E., M.E. Bohlen, S. Warren, P.J. May (2012) Evidence for the central mesencephalic reticular formation playing a role in the near triad.  Eye Movement GRC.
    • Bohlen, M.O., S. Warren, A.P. Moreno, P.J. May. (2013) Does the fastigial nucleus project directly to oculomotor motoneurons? Soc. Neurosci. Abst. 39:363.04.
    • May, P.J., M.O. Bohlen, S. Warren (2013) Morphology and distribution of two inputs to the oculomotor nucleus in the macaque. Soc. Neurosci. Abst. 39: 363.03.
    • Bohlen, M.O., S. Warren, R. Blumer, J.F. Stahl, P.J. May (2014) The organization of extraocular muscle motoneuronal pools in the mouse. Soc. Neurosci. Abst. 40: 62.12
    • Barnerssoi, M., P.J. May, A.K.E. Horn (2014) GABAergic innervation of the monkey ciliary ganglion - An electron microscopy study. Soc. Neurosci. Abst. 40: 62.05.
    • Bohlen, M.O., S. Warren and P.J. May (2015) Central Mesencephalic Reticular Formation Projections to Horizontal Gaze Motoneurons - A Green Light or Red? Soc. Neurosci. Abst. 41:

    Previous academic appointments

    • 1986: Instructor, Department of Physiology & Biophysics, New York University Medical Center , New York, NY
    • 1986-91: Assistant Professor, Department of Anatomy, UMMC, Jackson, MS
    • 1991-2005: Associate Professor, Department of Anatomy, UMMC, Jackson, MS

    Accomplishments and honors

    • 1995: Chair, Neuronal Control of Movement Workshop
    • 1997-2000: Evers' Society All Star Teacher
    • 2002-03: Casey Elementary PTA Parent of the Year
    • 2003: Excellence in Research Award (Gold Level), UMMC
    • 2005-07: Co-Vice Chair, Oculomotor Systems Biology Gordon Conference
    • 2006: Basic Science Teacher of the Year
    • 2010-11: Co-Chair, Eye Movements Gordon Conference 
    • 2013, 2015: Session Leader, Eye Movements Gordon Conference