Unitary Potentials Research Articles

Rubrally evoked unitary potentials in ventro-lateral thalamus of cat

The mechanism of rubrally evoked single unit potentials in ventro-lateral thalamus was explored by means of extra- and intracellular recording of neurons in cats anesthetized with Fluothane-nitrous oxide or Nembutal and paralyzed with Flaxedil. Unitary responses had a latency ranging from 0.8 to 500 msec. Bursts of spike responses coincided with crests of depolarization, more consistently after the first hyperpolarizing wave following the stimulus. Although spike potentials were usually associated with slow post-synaptic potentials, neither was necessary for the appearance of the other. The duration of inhibitory post-synaptic potentials ranged from 50 to 500 msec depending on the stimulus strength or number of pulses of the stimulating train. Some neurons displayed a capacity to follow frequencies of stimulation up to 100/sec. Fewer units could follow higher frequencies. There was a clear interdependence between cell response frequency, frequency of stimulation and strength of each individual pulse of the train. High sensitivity intra- or juxtacellular recording may reveal important interactive firing patterns between two very closely adjacent neurons. The functional significance of this interaction was discussed.

RECURRENT FACILITATION OF FROG MOTONEURONS.

ArticlesRECURRENT FACILITATION OF FROG MOTONEURONSKisou Kubota, and John M. BrookhartKisou Kubota, and John M. BrookhartPublished Online:01 Nov 1963https://doi.org/10.1152/jn.1963.26.6.877MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformationCited ByElectrophysiology of adult rat facial motoneurones: the effects of serotonin (5-HT) in a novel in vitro brainstem sliceJournal of Neuroscience Methods, Vol. 28, No. 1-2Excitatory postsynaptic currents in response to different synaptic inputs of frog spinal motoneuronsNeuroscience Research, Vol. 5, No. 3Effects of changes in osmolality on spinal cord activityExperimental Neurology, Vol. 68, No. 3Intracellular synaptic potentials of primate motor cortex neurons during voluntary movementBrain Research, Vol. 163, No. 1Dual effects of acetylcholine on the spontaneous activity in the isolated perfused spinal cord of the frogNeuropharmacology, Vol. 17, No. 1The pharmacology of the amphibian spinal cordProgress in Neurobiology, Vol. 11, No. 1Electrotonic coupling between frog spinal motoneurons. An electrophysiological and morphological studyBrain Research, Vol. 138, No. 2Dendritic responses of frog motoneurons produced by antidromic activationNeuroscience, Vol. 1, No. 6The morphology of motoneurons and dorsal root fibers in the frog's spinal cordBrain Research, Vol. 103, No. 2Presynaptic modulation of synaptic effectiveness of afferent and ventrolateral tract fibers in the frog spinal cordExperimental Neurology, Vol. 45, No. 3Light and electron microscopy of motoneurons and neuropile in the amphibian spinal cordBrain Research, Vol. 31, No. 1Acetylcholine depolarization of the dorsal root nerve terminals in the amphibian spinal cordInternational Journal of Neuropharmacology, Vol. 8, No. 4Inhibitory interaction between motoneurons of adjacent segments in the frog spinal cordExperimental Neurology, Vol. 23, No. 2Facilitatory and excitatory interaction between motoneurons of adjacent segments in the spinal cord of the frogExperimental Neurology, Vol. 20, No. 4Differences between monosynaptic and polysynaptic excitatory post-synaptic potentials of cat motoneurons during current injectionBrain Research, Vol. 3, No. 4Rubrally evoked unitary potentials in ventro-lateral thalamus of catElectroencephalography and Clinical Neurophysiology, Vol. 21, No. 3 More from this issue > Volume 26Issue 6November 1963Pages 877-893 https://doi.org/10.1152/jn.1963.26.6.877PubMed14084164History Published online 1 November 1963 Published in print 1 November 1963 Metrics

Intracellular recording from thalamic neurons during reticulocortical activation.

Intracellular recording from thalamic neurons during reticulocortical activation.

Thalamic projections of spinothalamic pathways in monkey

The thalamic distribution of peripherally initiated sensory activity which ascends through the ventrolateral fasciculus of the spinal cord has been studied in monkeys in which the dorsal columns had been sectioned. Evoked unitary discharges were routinely recorded from the external segment of the ventrobasal complex in these animals following stimulation of discrete portions of the body. Evidence was obtained which indicated that this spinothalamic projection is somatotopically organized with reference to the body surface. Other thalamic nuclei from which evoked responses were recorded included cell groups of internal medullary lamina and the centrum medianum. Unitary potentials or multiunit recordings from these other responsive zones were found to be evoked by inputs stemming from large, frequently bilateral areas of the body. In addition, nuclei were also shown to respond which were homologous to some of those comprising the posterior nuclear group in cat. The active points in the posterior region also did not show a somatotopic arrangement of the ventrobasal type and were initiated by stimulation of bilateral peripheral inputs. In two instances, responses were also recorded in the external medullary lamina. These results indicate that the spinothalamic systems of monkey are comprised of pathways through which an area to point relationship exists between the opposite side of the body and the ventrobasal complex, and of diffuse projections which carry input from wide areas of body surface to nuclei adjacent to the ventrobasal complex.

REPETITIVE DISCHARGE OF NEURONS

ArticlesREPETITIVE DISCHARGE OF NEURONSPatrick D. WallPatrick D. WallPublished Online:01 May 1959https://doi.org/10.1152/jn.1959.22.3.305MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByCharacterization and pharmacological modulation of noci-responsive deep dorsal horn neurons across diverse rat models of pathological painSteve McGaraughty, Katharine L. Chu, and Jun Xu5 October 2018 | Journal of Neurophysiology, Vol. 120, No. 4Slow changes in the flexion reflex of the rat following arthritis or tenotomyBrain Research, Vol. 447, No. 2Toward a neuropsychopharmacology of habituation: A vertical integrationMathematical Modelling, Vol. 7, No. 5-8The function of dendritic spines: A theoretical studyNeuroscience, Vol. 15, No. 4Stimulus-response profile analysis: a comprehensive, quantitative approach to the study of sensory coding and information processingJournal of Neuroscience Methods, Vol. 5, No. 4Lamina-specific alteration of C-fibre evoked activity by morphine in the dorsal horn of the rat spinal cordNeuroscience Letters, Vol. 25, No. 1Relation of terspike baseline activity to the spontaneous discharges of primary afferents from the labyrinth of the toadfish,Opsanus tauBrain Research, Vol. 150, No. 1A program for generating ON-LINE raster dot displays of single unit activityComputers and Biomedical Research, Vol. 11, No. 2Visual properties of neurons in the posterior suprasylvian gyrus of the catExperimental Neurology, Vol. 59, No. 1Periodicities of neurons controlled by slowly adapting cutaneous inputs in somatosensory thalamus of the catExperimental Neurology, Vol. 53, No. 3Burst and doublet firing modes within spinal cord dorsal horn cells of the chicken (Gallus domesticus)Brain Research, Vol. 117, No. 2Dorsal root reflex response in sympathetic nervesBrain Research, Vol. 111, No. 1Effects of peripheral afferent stimulation on dorsal horn neurons in the chicken (Gallus domesticus)Experimental Neurology, Vol. 49, No. 3Electrophysiological and cytological studies of brain homografts in the anterior chamber of the eye: Maturation of cerebellar cortex in oculoBrain Research, Vol. 79, No. 2Synaptic potentials of hypoglossal motoneurons and a common inhibitory interneuron in the trigemino-hypoglossal reflexBrain Research, Vol. 73, No. 3Antidromic electrical interaction between alpha motoneurons and presynaptic terminalsBrain Research, Vol. 57, No. 1Interactions of sensory and nonspecific thalamic inputs to cortical polysensory units in the squirrel monkeyExperimental Neurology, Vol. 40, No. 1Variation in the response latency of cat retinal ganglion cellsVision Research, Vol. 13, No. 4Postsynaptic fibres in the dorsal columns and their relay in the nucleus gracilisBrain Research, Vol. 48Intraspinal latency, cutaneous fiber composition, and afferent control of the dorsal root reflex in catBrain Research, Vol. 47, No. 2Logic operations in the central nervous system-implications for information transfer mechanismsKybernetik, Vol. 11, No. 3Responses of single thalamic neurons to genital stimulation in female catsBrain Research, Vol. 33, No. 2Delayed firing of giant axons in the American cockroachJournal of Insect Physiology, Vol. 17, No. 8Local adaptation in cat LGN cells: evidence for a surround antagonismVision Research, Vol. 11, No. 6Burst activity of single units in the penicillin epileptogenic focusElectroencephalography and Clinical Neurophysiology, Vol. 29, No. 4Mechanoreceptor function in the razor clam: Sensory aspects of the foot withdrawal reflexComparative Biochemistry and Physiology, Vol. 35, No. 4Habituation and sensitization of spinal interneuron activity in acute spinal catBrain Research, Vol. 14, No. 2Response of cat dorsal horn cells to variations of intensity, location, and area of cutaneous stimuliExperimental Neurology, Vol. 23, No. 2Modulation of visual input to single neurones of the motor cortex by the primary visual area in the catBrain Research, Vol. 10, No. 2Evaluating membrane potential and spike patterns by experimenter-controlled computer displaysExperimental Neurology, Vol. 21, No. 4Rubrally evoked unitary potentials in ventro-lateral thalamus of catElectroencephalography and Clinical Neurophysiology, Vol. 21, No. 3Modulation of the thalamic relay of taste by stimulation of the tongue with ice waterExperimental Neurology, Vol. 16, No. 1Uninhibited Reversible Antidromic Vasodilation in Pathophysiologic Diseases: Arteriosclerosis, Carcinogenesis, Neuritis, and Osteoporosis2 July 2016 | Angiology, Vol. 17, No. 2Response patterns of thalamic neurons during classical conditioningElectroencephalography and Clinical Neurophysiology, Vol. 17, No. 5Masking and metacontrast phenomena in the skin sensory systemExperimental Neurology, Vol. 8, No. 1Dependence of the response characteristics of somatosensory neurons on the form of their afferent inputExperimental Neurology, Vol. 6, No. 5 More from this issue > Volume 22Issue 3May 1959Pages 305-320 https://doi.org/10.1152/jn.1959.22.3.305PubMed13642103History Published online 1 May 1959 Published in print 1 May 1959 Metrics

Slow membrane potential changes accompanying excitation and inhibition in spinal moto- and interneurons in the cat during natural activation.

Summary.Slow membrane potential changes accompanying excitation and inhibition processes have been studied in spinal moto‐ and inter‐neurons of spinal cats, using intracellular recording technique.Section I. Long‐lasting shifts in membrane potential level have been recorded in both moto‐ and interneurons during sustained rhythmical activity.A closer study of the slow membrane potential changes and their relation to spike potentials has revealed fundamentally similar events in moto‐ and interneurons; the quantitative analyses have mainly been performed on niotoneurons whose steady membrane potentials allow of studies for sufficiently long periods. Special attention has been given to the slow membrane potential oscillations during rhythmical firing.The firing level for the onset of rhythmical spike discharges was found to be relatively constant in one and the same neuron; with increase in discharge frequency a definite lowering of the firing level occurs, an approximately linear relation being found to exist between firing level and impulse interval.During periods of regular rhythmical firing subthreshold membrane potential oscillations may occasionally he seen associated with spikes of reduced amplitude or not accompanied by any recordable spikes.The potential analysis has led to a tentative differentiation between an initial quick and a later slow phase of repolarization. The quick repolarization level, more or less marked in different neurons, is of approximately the same value during natural activation and single ortho‐ or antidromic stimulation; it varies within relatively narrow limits during the large natural variations in membrane potential observed in the experiments.The slow repolarization level, which may show great variations even at one and the same membrane potential level, undergoes a pronounced reduction with increasing frequency of the rhythmical activity. The relation hetween the slow repolarization level and the impulse interval is found to be approximately linear.The typical variations in quick and slow membrane processes during various activity levels of a motoneuron have been diagrammatically represented. The possibility is discussed that the quick spike processes and slow potential variations represent changes in different membrane potential fractions, analogous to the Q‐ and L‐fractions established in peripheral nerve.The evidences in favour of an inherent oscillation mechanism in the inembrane activated at a critical level of depolarization and primarily responsible for the discharge frequency are discussed.Section II. Membrane potential changes during inhibition have been studied in moto‐ and interneurons using exteroceptive inhibitory stimulation. In both types of neurons natural activation of inhihitory sources resulted in a slow repolarization not exceeding the highest membrane potential recorded in the absence of excitatory stimulation.The inhibitory effects of synchronized afferent volleys have been analysed in motoneurons in different states of rhythmical activity. The amplitude of the repolarization dip produced by each afferent volley was found to depend on the membrane potential level at the onset of inhibition. During repetitive stimulation a steady state was gradually attained, the level of which varied with the initial state of activity of the neuron.Section III. Both in moto‐ and interneurons the occurrence of random miniature potentials of varying amplitude has been demonstrated, those of larger amplitude (10 mV) apparently being built up out of the smaller “unitary potentials” of 1–3 mV.Increase as well as decrease of the miniature potential activity could be produced by natural activation of extero‐ or proprioceptive sources influencing the neuron. Correlations to the membrane potential level showed a reduced amplitude range of miniature potentials during increased membrane potential.In addition to the most common type of miniature potentials representing an inside positive change, potentials of the opposite sign were occasionally observed. The functional role of such randomly occurring repolarization potentials has been exemplified and a comparison made with similar phenomena observed in other types of nerve cells.