John Simpson

John SimpsonProfessor Emeritus, Department of Neuroscience & Physiology 

550 First Avenue
Room 462 Medical Science Building
New York, NY 10016
Phone: 212-263-5428

Research Summary:

Recording of cerebellar interneuronal responses to natural visual and vestibular stimulation

In a broad sense, we design our research to understand the cerebellar contribution to sensorimotor integration by investigating in the rabbit the neuronal signal processing associated with eye movements elicited by natural stimuli. The experimental method mostly is correlating extracellularly recorded Purkinje cell activity with natural visual, vestibular, and proprioceptive stimuli and with the compensatory eye movement responses. We focus on the cerebellar flocculus and the distribution of Purkinje cell complex and simple spike activity located in anatomically distinguishable modules. The hypothesis is that cerebellar signal processing entails mapping within and between intrinsic reference frames and that these have an anatomical counterpart in the modular organization of the cerebellum.

Selected Publications:

  • Ruigrok TJH, Hensbroek RA, and Simpson JI (2011) Spontaneous activity signatures of morphologically identified interneurons in the vestibulocerebellum. J. Neuroscience. 31: 712-724

  • Simpson JI (2011) Crossing zones in the vestibulocerebellum: a commentary. Cerebellum. 3: 515-522

  • Maruta J, Raphan T, Simpson JI, and Cohen B (2008) Vertical (Z-axis) acceleration alters the ocular response to linear acceleration in the rabbit. Experimental Brain Research. 185: 87-99

  • Maruta J, MacDougall HG, Simpson JI, Raphan T, and Cohen B (2006) Eye velocity asymmetry, ocular orientation, and convergence induced by angular rotation in the rabbit. Vision Research. 46: 961-969

  • Urbano FJ, Simpson JI, Llinas RR (2006) Somatomotor and oculomotor inferior olivary neurons have distinct electrophysiological phenotypes. Profeedings of the National Academy of Sciences of the United States of America. 44: 16550-16555