Biomaterial Database

Purkinje cell activity in the flocculus of vestibular neurectomized and normal monkeys during optokinetic nystagmus (OKN) and smooth pursuit eye movements. 1985

W Waespe, and D Rudinger, and M Wolfensberger

Single unit activity was recorded in the primate flocculus after the vestibular nerves were cut (bilateral vestibular neurectomy) during optokinetic nystagmus (OKN), smooth pursuit eye movements (SP) and whole field visual stimulation with gaze fixed on a stationary target light (OKN-suppression). Following vestibular neurectomy monkeys had no vestibular responses and no optokinetic after-nystagmus (OKAN) in the horizontal plane. However, OKN slow phases still reached steady state velocities of up to 100 deg/s. After neurectomy, simple spike (SS) activity of Purkinje cells (P-cells) was modulated in relation to eye velocity, regardless of whether eye velocity was induced by a small target light moving in darkness (SP) or by a moving visual surround (OKN). In over 90% of the P-cells firing rate increased with eye velocity to the ipsilateral side and decreased with velocities to the contralateral side. Modulation in firing rate increased monotonically with increasing eye velocity. The strength of modulation was similar during SP and OKN for the same eye velocity. The change in firing rate of P-cells in response to a sudden change in optokinetic stimulus velocity contained a component related to eye velocity and a component related to eye acceleration. Only a few P-cells were also modulated with image slip velocity during OKN-suppression. The modulation of P-cells during SP and OKN was compared in normal and vestibular neurectomized monkeys. The sensitivity of floccular P-cells to eye velocity during SP was 1.14 imp X s-1/deg X s-1 in normal monkey and 1.28 imp X s-1/deg X s-1 after neurectomy. The similarity of eye velocity sensitivities demonstrates that neurectomy does not change the characteristics of floccular P-cell modulation during SP. In contrast, during OKN modulation of P-cells is quite different in normal and neurectomized monkey. In normal monkey, P-cells are modulated during steady state OKN for eye velocities above 40-60 deg/s only. This threshold velocity corresponds approximately to the maximal initial OKAN velocity (i.e. OKAN saturation velocity). After neurectomy, the threshold velocity is 0 deg/s and P-cells are modulated during steady state OKN also over ranges of eye velocities that do not cause a response in normal monkey. Sensitivities of P-cells to eye velocity during OKN for eye velocities above the threshold velocity are 1.0 imp X s-1/deg X s-1 in neurectomized monkey and 1.43 imp X s-1/deg X s-1 in normal monkey.(ABSTRACT TRUNCATED AT 400 WORDS)

UI	MeSH Term	Description	Entries
D008252	Macaca fascicularis	A species of the genus MACACA which typically lives near the coast in tidal creeks and mangrove swamps primarily on the islands of the Malay peninsula.	Burmese Long-Tailed Macaque,Crab-Eating Monkey,Cynomolgus Monkey,M. f. aurea,M. fascicularis,Macaca fascicularis aurea,Monkey, Crab-Eating,Monkey, Cynomolgus,Crab-Eating Macaque,Burmese Long Tailed Macaque,Crab Eating Macaque,Crab Eating Monkey,Crab-Eating Macaques,Crab-Eating Monkeys,Cynomolgus Monkeys,Long-Tailed Macaque, Burmese,Macaque, Burmese Long-Tailed,Macaque, Crab-Eating,Monkey, Crab Eating
D008253	Macaca mulatta	A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.	Chinese Rhesus Macaques,Macaca mulatta lasiota,Monkey, Rhesus,Rhesus Monkey,Rhesus Macaque,Chinese Rhesus Macaque,Macaca mulatta lasiotas,Macaque, Rhesus,Rhesus Macaque, Chinese,Rhesus Macaques,Rhesus Macaques, Chinese,Rhesus Monkeys
D009760	Nystagmus, Physiologic	Involuntary rhythmical movements of the eyes in the normal person. These can be naturally occurring as in end-position (end-point, end-stage, or deviational) nystagmus or induced by the optokinetic drum (NYSTAGMUS, OPTOKINETIC), caloric test, or a rotating chair.	Nystagmus, Barany,Nystagmus, Caloric,Nystagmus, End-Position,Nystagmus, Positional,Nystagmus, Post-Rotatory,Nystagmus, Thermal,Nystagmus, Barany's,Nystagmus, Physiological,Physiologic Nystagmus,Barany Nystagmus,Barany's Nystagmus,Caloric Nystagmus,End-Position Nystagmus,Nystagmus, Baranys,Nystagmus, End Position,Nystagmus, Post Rotatory,Physiological Nystagmus,Positional Nystagmus,Post-Rotatory Nystagmus,Thermal Nystagmus
D011689	Purkinje Cells	The output neurons of the cerebellar cortex.	Purkinje Cell,Purkinje Neuron,Purkyne Cell,Cell, Purkinje,Cell, Purkyne,Cells, Purkinje,Cells, Purkyne,Neuron, Purkinje,Neurons, Purkinje,Purkinje Neurons,Purkyne Cells
D011698	Pursuit, Smooth	Eye movements that are slow, continuous, and conjugate and occur when a fixed object is moved slowly.	Pursuits, Smooth,Smooth Pursuit,Smooth Pursuits
D001931	Brain Mapping	Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.	Brain Electrical Activity Mapping,Functional Cerebral Localization,Topographic Brain Mapping,Brain Mapping, Topographic,Functional Cerebral Localizations,Mapping, Brain,Mapping, Topographic Brain
D002525	Cerebellar Cortex	The superficial GRAY MATTER of the CEREBELLUM. It consists of two main layers, the stratum moleculare and the stratum granulosum.	Cortex Cerebelli,Cerebelli, Cortex,Cerebellus, Cortex,Cortex Cerebellus,Cortex, Cerebellar
D005133	Eye Movements	Voluntary or reflex-controlled movements of the eye.	Eye Movement,Movement, Eye,Movements, Eye
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia