The goal of the proposed research is to understand the vestibulo-cervical reflex, also called the vestibulo-colic reflex (VCR). The neuronal circuitry of the VCR receives vestibular information from the semicircular canals and otoliths, and coordinates neck muscle contraction in response to vestibular stimuli. When the VCR is disabled the head wobbles rapidly and uncontrollably, demonstrating that one VCR function is to maintain head stability. Head and body righting reflexes are also disrupted by interruption of vestibular signals, suggesting that another VCR function is righting the head to maintain the usual upright posture. The proposed research to be done in squirrel monkeys and cats has two major hypotheses with corresponding experimental aims: 1. The Vestibulo-Cervical Reflex returns the head to the upright position: when the head is upright and intermediate frequencies of head motion are tested, a stabilizing VCR responses is observed. However, when the head is not upright and low frequencies are tested, responses can oppose head stability if such opposition would facilitate righting of the head. Neck muscle electromyographic activity and brainstem VCR neuron activity will be recorded during low-frequency head rotations in a variety of head postures to determine when stabilizing responses occur and when righting responses are elicited by head motion. 2. Vestibulo-Cervical Reflex signals can dominate vestibulo-ocular reflexes: Reflex eye movements will be recorded at the same time as neck muscle electromyographic and VCR neuron activity to determine if ocular reflexes are altered by the transition of VCR response from a stabilizing to righting function. Activity of neurons participating in both reflexes will be recorded to see which reflex dominates.

National Institute of Health (NIH)
National Institute on Deafness and Other Communication Disorders (NIDCD)
Research Project (R01)
Project #
Application #
Study Section
Hearing Research Study Section (HAR)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Northwestern University at Chicago
Schools of Dentistry
United States
Zip Code
Baizer, Joan S; Corwin, Will L; Baker, James F (2010) Otolith stimulation induces c-Fos expression in vestibular and precerebellar nuclei in cats and squirrel monkeys. Brain Res 1351:64-73
Brettler, Sandra C; Baker, James F (2006) Anterior canal neurons in cat vestibular nuclei have large phase leads during low frequency vertical axis pitch. J Vestib Res 16:245-56
Baizer, Joan S; Baker, James F (2006) Neurochemically defined cell columns in the nucleus prepositus hypoglossi of the cat and monkey. Brain Res 1094:127-37
Baizer, Joan S; Baker, James F (2006) Immunoreactivity for calretinin and calbindin in the vestibular nuclear complex of the monkey. Exp Brain Res 172:103-13
Baker, James F (2005) Dynamics and directionality of the vestibulo-collic reflex (VCR) in mice. Exp Brain Res 167:108-13
Baizer, Joan S; Baker, James F (2005) Immunoreactivity for calcium-binding proteins defines subregions of the vestibular nuclear complex of the cat. Exp Brain Res 164:78-91
Sekerkova, Gabriella; Ilijic, Ema; Mugnaini, Enrico et al. (2005) Otolith organ or semicircular canal stimulation induces c-fos expression in unipolar brush cells and granule cells of cat and squirrel monkey. Exp Brain Res 164:286-300
Killian, J Eric; Baker, James F (2005) Electromyographic activity of dorsal neck muscles in squirrel monkeys during rotations in an upright or upside down posture. J Neurophysiol 93:2587-99
Brettler, Sandra C; Baker, James F (2003) Timing of low frequency responses of anterior and posterior canal vestibulo-ocular neurons in alert cats. Exp Brain Res 149:167-73
Harrod, Christopher G; Baker, James F (2003) The vestibulo ocular reflex (VOR) in otoconia deficient head tilt (het) mutant mice versus wild type C57BL/6 mice. Brain Res 972:75-83

Showing the most recent 10 out of 20 publications