Responses to Tactile Stimulation in Deep Cerebellar Nucleus Neurons Result From Recurrent Activation in Multiple Pathways

• Type of Material: Article
• Authors: Nathan C. Rowland, Emory University; Dieter Jaeger, Emory University
• Language: English
• Date: 2008-02-01
• Publisher: American Physiological Society
• Publication Version: Final Published Version
• Copyright Statement: © 2007 by the American Physiological Society.
• Final Published Version (URL): https://doi.org/10.1152/jn.01100.2007
• Title of Journal or Parent Work: Journal of Neurophysiology
• Grant/Funding Information: The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.; This work was supported by National Institutes of Health Grants RO1 MH-065634, and F31 GM-020685.
• Keywords: inferior olive; local field potential; single unit; somatosensory; cerebral cortex
• Research Categories: Biology, Neuroscience

Abstract

In a previous study, we found that neurons in the deep cerebellar nuclei (DCN) respond to 5-ms brief facial tactile stimulation in rats anesthetized with ketamine-xylazine with multiphasic response patterns lasting over 200 ms. It remained unclear, however, to what extent these responses were shaped not only by ascending sensory input from the trigeminal nuclei but also by interactions with other major cerebellar afferent systems, in particular the inferior olive (IO) and cerebral cortex. In the present study, we recorded from the IO, cerebral cortex, cerebellar granule cell layer (GCL), and DCN during the presentation of 5-ms facial tactile stimuli to elucidate potential mechanisms of how extended DCN response patterns are generated. We found that tactile stimulation resulted in robust multiphasic local field potentials responses in the IO as well as in the activation of a wide region of the somatosensory cortex (SI) and the primary motor cortex (MI). DCN neurons responded to electrical stimulation of any of these structures (IO, SI, and MI) with complex temporal patterns strikingly similar to air-puff lip stimulation responses. Simultaneous recordings from multiple structures revealed that long-lasting activation patterns elicited in DCN neurons were based on recurrent network activation in particular between the IO and the DCN with a potential contribution of DCN rebound properties. These results are consistent with the hypothesis that sensory stimulation triggers a feedback network activation of cerebellum, IO, and cerebral cortex to generate temporal patterns of activity that may control the timing of behavior.