When walking in natural habitats, animals and humans must control the transfer and placement of their feet precisely in order to avoid numerous obstacles and irregularities. While the basic order of muscular contractions during locomotion is determined by the spinal cord, it is the activity of supraspinal centers that modifies locomotion by taking into account visual information. The overall aim of this project is to understand the neuronal mechanisms of the forebrain that are involved in adaptation of locomotion to the visually perceived features of the environment. All data will be obtained from cats walking inside an experimental chamber (1) on a flat surface where no visuo-motor coordination will be required (simple locomotion) and (2) along a horizontal ladder where visuo-motor coordination for an accurate foot placement on the cross-pieces will be required (complex locomotion). We will record the activity of identified neurons in motor and parietal cortex, and in motor thalamus. We will then reversibly block various inputs to these neurons to understand the contribution that these inputs make to the formation of signals for control of visually guided stepping.
In Aim 1, we will study the roles of ventrolateral thalamus, parietal area 5, and GABAA intra-cortical mechanisms in the formation of simple and complex locomotion-related activity of pyramidal tract and thalamus projecting neurons of the motor cortex.
In Aim 2, we will examine the activity of the reticular nucleus of thalamus and the role of inputs from lateral and interposed nuclei of cerebellum in the formation of simple and complex locomotion-related activity in ventrolateral thalamus. The proposed study will reveal important neuronal mechanisms of the forebrain for control of visually guided locomotion. The study may have significant clinical applications. In forebrain stroke patients, selection of rehabilitation strategies for locomotion deficits depends largely on an elucidation of the role of direct forebrain control of locomotion in relation to spinal mechanisms. The proposed study will reveal neuronal mechanisms of the forebrain, which are involved in adaptation of locomotion to the visually perceived features of the environment. This is a vital motor function of the brain. In forebrain stroke patients, selection of rehabilitation strategies for locomotion deficits depends largely on an elucidation of the role of forebrain in control of locomotion.
|Zubair, Humza N; Beloozerova, Irina N; Sun, Hai et al. (2016) Head movement during walking in the cat. Neuroscience 332:101-20|
|Favorov, Oleg V; Nilaweera, Wijitha U; Miasnikov, Alexandre A et al. (2015) Activity of somatosensory-responsive neurons in high subdivisions of SI cortex during locomotion. J Neurosci 35:7763-76|
|Farrell, Brad J; Bulgakova, Margarita A; Sirota, Mikhail G et al. (2015) Accurate stepping on a narrow path: mechanics, EMG, and motor cortex activity in the cat. J Neurophysiol 114:2682-702|
|Stout, Erik E; Sirota, Mikhail G; Beloozerova, Irina N (2015) Known and unexpected constraints evoke different kinematic, muscle, and motor cortical neuron responses during locomotion. Eur J Neurosci 42:2666-77|
|Farrell, Brad J; Bulgakova, Margarita A; Beloozerova, Irina N et al. (2014) Body stability and muscle and motor cortex activity during walking with wide stance. J Neurophysiol 112:504-24|
|Klishko, Alexander N; Farrell, Bradley J; Beloozerova, Irina N et al. (2014) Stabilization of cat paw trajectory during locomotion. J Neurophysiol 112:1376-91|
|Rivers, T J; Sirota, M G; Guttentag, A I et al. (2014) Gaze shifts and fixations dominate gaze behavior of walking cats. Neuroscience 275:477-99|
|Marlinski, Vladimir; Beloozerova, Irina N (2014) Burst firing of neurons in the thalamic reticular nucleus during locomotion. J Neurophysiol 112:181-92|
|Stout, Erik E; Beloozerova, Irina N (2013) Differential responses of fast- and slow-conducting pyramidal tract neurons to changes in accuracy demands during locomotion. J Physiol 591:2647-66|
|Armer, Madison C; Nilaweera, Wijitha U; Rivers, Trevor J et al. (2013) Effect of light on the activity of motor cortex neurons during locomotion. Behav Brain Res 250:238-50|
Showing the most recent 10 out of 19 publications