Biomaterial Database

Superposition of antidromic responses in pyramidal tract cell clusters. 1985

A Canedo, and A L Towe

Large-seeing-distance microelectrodes were used to record simultaneously the activity of several pyramidal tract neurons in cerebral cortex. When activated antidromically, these neurons responded simultaneously, forming a "stack" of superimposed spikes, rather than responding at different times within the 10-ms time interval during which they might be expected to respond. Using a variety of spike collision tests, we found that these individual spikes arose from separate sources and reflected the activity of individual, albeit neighboring, pyramidal tract neurons. The collaterals of neurons within a stack projected to different structures, further verifying that separate neurons were involved. Such synchrony of antidromic activity among neighboring pyramidal tract neurons is an exceedingly low-probability event, if neighboring fibers conduct independently of one another. Our results imply that fibers from small clusters of neurons in the cortex assemble to form synchronously conducting bundles of fibers within the pyramidal tract.

UI	MeSH Term	Description	Entries
D008839	Microelectrodes	Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)	Electrodes, Miniaturized,Electrode, Miniaturized,Microelectrode,Miniaturized Electrode,Miniaturized Electrodes
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
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D011336	Probability	The study of chance processes or the relative frequency characterizing a chance process.	Probabilities
D011712	Pyramidal Tracts	Fibers that arise from cells within the cerebral cortex, pass through the medullary pyramid, and descend in the spinal cord. Many authorities say the pyramidal tracts include both the corticospinal and corticobulbar tracts.	Corticobulbar Tracts,Corticospinal Tracts,Decussation, Pyramidal,Corticobulbar Tract,Corticospinal Tract,Pyramidal Decussation,Pyramidal Tract,Tract, Corticobulbar,Tract, Corticospinal,Tract, Pyramidal,Tracts, Corticobulbar,Tracts, Corticospinal,Tracts, Pyramidal
D011930	Reaction Time	The time from the onset of a stimulus until a response is observed.	Response Latency,Response Speed,Response Time,Latency, Response,Reaction Times,Response Latencies,Response Times,Speed, Response,Speeds, Response
D012012	Red Nucleus	A pinkish-yellow portion of the midbrain situated in the rostral mesencephalic tegmentum. It receives a large projection from the contralateral half of the CEREBELLUM via the superior cerebellar peduncle and a projection from the ipsilateral MOTOR CORTEX.	Nucleus Ruber,Nucleus, Red
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
D004056	Differential Threshold	The smallest difference which can be discriminated between two stimuli or one which is barely above the threshold.	Difference Limen,Just-Noticeable Difference,Weber-Fechner Law,Difference Limens,Difference, Just-Noticeable,Differences, Just-Noticeable,Differential Thresholds,Just Noticeable Difference,Just-Noticeable Differences,Law, Weber-Fechner,Limen, Difference,Limens, Difference,Threshold, Differential,Thresholds, Differential,Weber Fechner Law
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