Neural Substrate of Modified and Unmodified Pathways for Learning in Monkey Vestibuloocular Reflex
Open Access
- 1 October 2008
- journal article
- research article
- Published by American Physiological Society in Journal of Neurophysiology
- Vol. 100 (4), 1868-1878
- https://doi.org/10.1152/jn.90498.2008
Abstract
To understand how the brain learns, we need to identify the full neural circuit for a behavior; characterize how neural responses in the circuit change during behavioral learning; and understand the nature, location, and control of the cellular changes that are responsible for learning. This goal seems attainable for the vestibuloocular reflex (VOR), where the neural circuit basis for learning is already partially understood. The current hypothesis for VOR learning postulates cellular changes in the cerebellar cortex and the vestibular nucleus. It suggests that the brain stem contains two parallel pathways that have been modeled on the basis of extensive biological data as unmodified and modified VOR pathways with frequency-dependent internal gains and different time delays. We now show a correspondence between the responses of different groups of neurons in the vestibular nucleus and the signals emanating from the two pathways in the model. Floccular target neurons (FTNs) and position-vestibular-pause neurons (PVPs) were identified by their discharge during eye movements and by the presence or absence of inhibition by floccular stimulation. FTNs had response gains and phases that coincided with predictions for pathways that are modified in association with learning, whereas PVPs had responses in agreement with predictions for the unmodified pathways. The quantitative agreement of prior model predictions and new data supports the identity of FTNs and PVPs as brain stem interneurons in the modified and unmodified VOR pathways. Other aspects of the data make predictions about how vestibular inputs are transformed as they pass through the two pathways.Keywords
This publication has 37 references indexed in Scilit:
- Firing Properties of GABAergic Versus Non-GABAergic Vestibular Nucleus Neurons Conferred by a Differential Balance of Potassium CurrentsJournal of Neurophysiology, 2007
- Neural Variability, Detection Thresholds, and Information Transmission in the Vestibular SystemJournal of Neuroscience, 2007
- Transformation of Vestibular Signals Into Motor Commands in the Vestibuloocular Reflex Pathways of MonkeysJournal of Neurophysiology, 2006
- Physiological and Anatomical Properties of Mouse Medial Vestibular Nucleus Neurons Projecting to the Oculomotor NucleusJournal of Neurophysiology, 2006
- Chronic Changes in Inputs to Dorsal Y Neurons Accompany VOR Motor LearningJournal of Neurophysiology, 2006
- Normal Performance and Expression of Learning in the Vestibulo-Ocular Reflex (VOR) at High FrequenciesJournal of Neurophysiology, 2005
- Behavior of human horizontal vestibulo-ocular reflex in response to high-acceleration stimuliBrain Research, 1989
- The Latency of Pathways Containing the Site of Motor Learning in the Monkey Vestibulo-Ocular ReflexScience, 1984
- Visual Tracking and the Primate FlocculusScience, 1975
- A theory of cerebellar functionMathematical Biosciences, 1971