Biomaterial Database

The ventral spino-olivocerebellar system in the cat. III. Functional characteristics of the five paths. 1977

O Oscarsson, and B Sjölund

1. Five spino-olivocerebellar paths ascending through the ventral funiculus (VF-SOCPs) with different projection zones in the cerebellar cortex have been distinguished (Oscarsson and Sjöuld, 1977). The paths are denoted the a-, b1-, b2-, c1- and c3-VF-SOCPs according to the labelling of the projection zones. The functional organization of these paths has now been investigated. 2. All five paths are activated by the flexor reflex afferents from wide receptive fields (one or more limbs). Distal nerves are more effective in evoking responses than proximal nerves. 3. The a-, c1- and c3-paths are activated from the ipsilateral hindlimb only. The b1- and b2-paths are activated bilaterally from the forelimbs and hindlimbs, respectively. 4. The a-, b1- and b2-paths have long segmental delays indicating a polysynaptic linkage between the primary afferents and the tract neurones, whereas the c1- and c3-paths have short delays demonstrating a monosynaptic linkage. 5. The neurones giving origin to the paths are situated within a few segments of the dorsal root entrance. The axons cross the midline, ascend through the contralateral ventral funiculus, and activate the olivary neurones monosynaptically. 6. The spino-olivary tract of the c3-path has an upper conduction velocity of 30 m/s, whereas the other paths have upper conduction velocities of 40--45 m/s. 7. The segmental delay of the b1-VF-SOCP is much longer (mean 8.7 ms) than that of the b2-VF-SOCP (mean 3.9 ms). As a result simultaneous stimuli to the hindlimbs and forelimbs are signalled to reach the cerebellar cortex at the same time. 8. It is suggested that the information carried by the different paths is concerned with the segmental motor control.

UI	MeSH Term	Description	Entries
D009431	Neural Conduction	The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.	Nerve Conduction,Conduction, Nerve,Conduction, Neural,Conductions, Nerve,Conductions, Neural,Nerve Conductions,Neural Conductions
D009434	Neural Pathways	Neural tracts connecting one part of the nervous system with another.	Neural Interconnections,Interconnection, Neural,Interconnections, Neural,Neural Interconnection,Neural Pathway,Pathway, Neural,Pathways, Neural
D009847	Olivary Nucleus	A brainstem nuclear complex. in the hindbrain, also referred to as the olivary body. The olivary nuclear complex is a part of the MEDULLA OBLONGATA and the PONTINE TEGMENTUM. It is involved with motor control and is a major source of sensory input to the CEREBELLUM.	Basal Nucleus, Olivary,Nucleus Basalis, Olivary,Olivary Body,Olivary Complex,Olivary Nuclei,Complex, Olivary,Nucleus, Olivary,Nucleus, Olivary Basal,Olivary Basal Nucleus,Olivary Bodies
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
D012032	Refractory Period, Electrophysiological	The period of time following the triggering of an ACTION POTENTIAL when the CELL MEMBRANE has changed to an unexcitable state and is gradually restored to the resting (excitable) state. During the absolute refractory period no other stimulus can trigger a response. This is followed by the relative refractory period during which the cell gradually becomes more excitable and the stronger impulse that is required to illicit a response gradually lessens to that required during the resting state.	Period, Neurologic Refractory,Periods, Neurologic Refractory,Refractory Period, Neurologic,Tetanic Fade,Vvedenskii Inhibition,Wedensky Inhibition,Inhibition, Vvedenskii,Inhibition, Wedensky,Neurologic Refractory Period,Neurologic Refractory Periods,Neuromuscular Fade,Neuromuscular Transmission Fade,Refractory Period, Neurological,Refractory Periods, Neurologic,Electrophysiological Refractory Period,Electrophysiological Refractory Periods,Fade, Neuromuscular,Fade, Neuromuscular Transmission,Fade, Tetanic,Neurological Refractory Period,Neurological Refractory Periods,Refractory Periods, Electrophysiological,Refractory Periods, Neurological,Transmission Fade, Neuromuscular
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
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
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
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
D012584	Sciatic Nerve	A nerve which originates in the lumbar and sacral spinal cord (L4 to S3) and supplies motor and sensory innervation to the lower extremity. The sciatic nerve, which is the main continuation of the sacral plexus, is the largest nerve in the body. It has two major branches, the TIBIAL NERVE and the PERONEAL NERVE.	Nerve, Sciatic,Nerves, Sciatic,Sciatic Nerves