Faculty Opinions recommendation of Excitatory effect of GABAergic axo-axonic cells in cortical microcircuits.

2006 ◽  
Author(s):  
Kathleen Rockland
Keyword(s):  
Excitatory Effect ◽  
Cortical Microcircuits

Some effects of superior laryngeal nerve stimulation on sympathetic preganglionic neuron firing

1979 ◽  
Vol 57 (10) ◽  
pp. 1073-1081 ◽  
Author(s):  
Urs Gerber ◽  
Canio Polosa
Keyword(s):  
Firing Pattern ◽  
Superior Laryngeal Nerve ◽  
Inhibitory Effect ◽  
Laryngeal Nerve ◽  
Depressant Effect ◽  
Excitatory Effect ◽  
Sympathetic Preganglionic Neurons ◽  
Preganglionic Neurons ◽  
Phrenic Motoneurons ◽  
Frequency Of Stimulation

Repetitive electrical stimulation of afferent fibers in the superior laryngeal nerve (SLN) evoked depressant or excitatory effects on sympathetic preganglionic neurons of the cervical trunk in Nembutal-anesthetized, paralyzed, artificially ventilated cats. The depressant effect, which consisted of suppression of the inspiration-synchronous discharge of units with such firing pattern, was obtained at low strength and frequency of stimulation (e.g. 600 mV, 30 Hz) and was absent at end-tidal CO2 values below threshold for phrenic nerve activity. The excitatory effect required higher intensity and frequency of stimulation and was CO2 independent. The depressant effect on sympathetic preganglionic neurons with inspiratory firing pattern seemed a replica of the inspiration-inhibitory effect observed on phrenic motoneurons. Hence, it could be attributed to the known inhibition by the SLN of central inspiratory activity, if it is assumed that this is a common driver for phrenic motoneurons and some sympathetic preganglionic neurons. The excitatory effect, on the other hand, appears to be due to connections of SLN afferents with sympathetic preganglionic neurons, independent of the respiratory center.

Excitatory effect of ATP on acutely dissociated ventromedial hypothalamic neurons of the rat

Neuroscience ◽  
2001 ◽  
Vol 105 (2) ◽  
pp. 393-401 ◽  
Author(s):  
M Sorimachi ◽  
H Ishibashi ◽  
T Moritoyo ◽  
N Akaike
Keyword(s):  
Excitatory Effect ◽  
Hypothalamic Neurons

scholarly journals Reciprocal innervation and symmetrical muscles

1913 ◽  
Vol 86 (587) ◽  
pp. 219-232 ◽  
Keyword(s):  
Skeletal Muscles ◽  
Knee Extensor ◽  
General Rule ◽  
The Body ◽  
Ordinary Sense ◽  
Excitatory Effect ◽  
Biological Meaning ◽  
Vasomotor Reflexes ◽  
The One ◽  
The Right

If we attempt to decipher the biological meaning of reciprocal innervation its various instances when marshalled together say plainly that one of the functional problems which it meets and solves is mechanical antagonism. Where two muscles have directly opposed effect on the same lever, “reciprocal innervation” is the general rule observed by the nervous system in dealing with them, and this holds whether the reciprocal innervation is peripheral as with the antagonists of the arthropod claw, or is central as with vertebrate skeletal muscles. Also where one and the same muscle is governed by two nerves influencing it oppositely, reciprocal innervation seems again the principle followed in the co-ordination of the two opponent centres, as has been shown by Bayliss in his observations on vasomotor reflexes. But the distribution and occurrence of reciprocal innervation extend beyond cases of mere mechanical antagonism. The reflex influence exerted by the limb-afferents on symmetrical muscle-pairs such as right knee-extensor and left is reciprocal. Thus right peroneal nerve excites the motoneurones of left vastocrureus, and concomitantly inhibits those of the right. The reflex inhibition of the one is concurrent with, increases with increase, and decreases with decrease of, the excitatory effect on the other. Here the muscles are not in any ordinary sense antagonistic; not only do they not operate on the same lever, but they are not even members of the same limb, nor do they belong even to the same half of the body. They are, however, actuated conversely in the most usual modes of progression—the walking and the running step—though not always in galloping.

A Quantitative Study of the Behaviour of the Male Mormoniella Vitripennis (Walker) (Hymenoptera, Pteromalidae) Towards Two Constant Stimulus-Situations

Behaviour ◽  
1961 ◽  
Vol 18 (4) ◽  
pp. 288-311 ◽  
Author(s):  
Robert Barrass
Keyword(s):  
Nervous Activity ◽  
Specific Effect ◽  
Inhibitory Effect ◽  
Constant Stimulus ◽  
Receptive Female ◽  
Short Term ◽  
Excitatory Effect ◽  
Time Intervals ◽  
Almost All ◽  
Term Response

Abstract1. The method of dual quantification was used to study the effect of courtship of both receptive and non-receptive females on the subsequent behaviour of the male Mormoniella vitripennis. 2. The male's responsiveness to successive non-receptive females waned when the time between presentations was short. The extent of this waning was less with longer time intervals. 3. When many females were presented to a male one after another the male courted almost all of them if they were receptive females but only a few if they were non-receptive females. 4. A single courtship of either a receptive or a non-receptive female had a similar effect on the male's subsequent behaviour and recovery occurred in a similar way. 5. Courtship of 20 non-receptive females reduced the male's response to further females more than did courtship of 20 receptive females. 6. The significance of these observations is discussed with reference to the use of dummy animals and to the recent ethological concepts of reaction specific energy, motivational impulses, specific action potentiality and consummatory act. 7. An endogenous central nervous influence on the male's readiness to respond is postulated. Courtship has a short-term response-specific effect (receptive or non-receptive females) and an inhibitory stimulus-specific effect (non-receptive females). With receptive females the inhibitory effect is absent and/or mating has an excitatory effect. The stimuli provided by a receptive female must direct nervous activity rather than release a limited amount of stored energy.

scholarly journals Cutaneous inputs from perineal region facilitates and modulates spinal locomotor activity and reduces cutaneous reflexes from the foot in spinal cats

2020 ◽  
Author(s):  
Angèle N Merlet ◽  
Jonathan Harnie ◽  
Madalina Macovei ◽  
Adam Doelman ◽  
Nathaly Gaudreault ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Nerve Stimulation ◽  
Rhythmic Activity ◽  
Short Latency ◽  
Cutaneous Reflexes ◽  
Excitatory Effect ◽  
Reflex Responses ◽  
Cutaneous Reflex ◽  
Weight Support ◽  
Perineal Region

AbstractIt is well known that mechanically stimulating the perineal region potently facilitates hindlimb locomotion and weight support in mammals with a spinal transection (spinal mammals). However, how perineal stimulation mediates this excitatory effect is poorly understood. We evaluated the effect of mechanically stimulating (vibration or pinch) the perineal region on ipsilateral (9-14 ms onset) and contralateral (14-18 ms onset) short-latency cutaneous reflex responses evoked by electrically stimulating the superficial peroneal or distal tibial nerve in seven adult spinal cats where hindlimb movement was restrained. Cutaneous reflexes were evoked before, during, and after mechanical stimulation of the perineal region. We found that vibration or pinch of the perineal region effectively triggered rhythmic activity, unilateral and bilateral to nerve stimulation. When electrically stimulating nerves, adding perineal stimulation modulated rhythmic activity by decreasing cycle and burst durations and by increasing the amplitude of flexors and extensors. Perineal stimulation also disrupted the timing of the ipsilateral rhythm, which had been entrained by nerve stimulation. Mechanically stimulating the perineal region decreased ipsilateral and contralateral short-latency reflex responses evoked by cutaneous inputs, a phenomenon we observed in muscles crossing different joints and located in different limbs. The results suggest that the excitatory effect of perineal stimulation on locomotion and weight support is not mediated by increasing cutaneous reflex gain and instead points to an excitation of central pattern-generating circuitry. Our results are consistent with a state-dependent modulation of reflexes by spinal interneuronal circuits.Significance StatementMechanically stimulating the skin of the perineal region strongly facilitates hindlimb locomotion in mammals following a complete spinal cord injury (SCI). Despite its remarkable effectiveness in promoting hindlimb locomotion in spinal cord-injured mammals, we do not know how this is mediated. The present study provides data on how inputs from the perineal region interact with neuronal circuits that generate locomotor-like activity and reflexes from the foot. A better understanding of how inputs from the perineal region interact with neuronal circuits of the spinal cord could lead to non-invasive approaches to restore walking in people with SCI.

scholarly journals Short-latency afferent inhibition and somato-sensory evoked potentials during the migraine cycle: surrogate markers of a cycling cholinergic thalamo-cortical drive?

2020 ◽  
Author(s):  
Gianluca Coppola ◽  
Davide Di Lenola ◽  
Chiara Abagnale ◽  
Fabio Ferrandes ◽  
Gabriele Sebastianelli ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Evoked Potentials ◽  
Motor Evoked Potential ◽  
Short Latency ◽  
Excitatory Effect ◽  
Sensory Afferents ◽  
Short Latency Afferent Inhibition ◽  
Afferent Inhibition ◽  
Cycle Dependent ◽  
Sensory Evoked

Abstract Background: Short-latency afferent inhibition (SAI) consists of motor cortex inhibition induced by sensory afferents and depends on the excitatory effect of cholinergic thalamocortical projections on inhibitory GABAergic cortical networks. Given the electrophysiological evidence for thalamo-cortical dysrhythmia in migraine, we studied SAI in migraineurs during and between attacks and searched for correlations with somatosensory habituation, thalamocortical activation, and clinical features.Methods: SAI was obtained by conditioning the transcranial magnetic stimulation-induced motor evoked potential (MEP) with an electric stimulus on the median nerve at the wrist with random stimulus intervals corresponding to the latency of individual somatosensory evoked potentials (SSEP) N20 plus 2, 4, 6, or 8 ms. We recruited 30 migraine without aura patients, 16 between (MO), 14 during an attack (MI), and 16 healthy volunteers (HV). We calculated the slope of the linear regression between the unconditioned MEP amplitude and the 4-conditioned MEPs as a measure of SAI. We also measured SSEP amplitude habituation, and high-frequency oscillations (HFO) as an index of thalamo-cortical activation.Results: Compared to HV, SAI, SSEP habituation and early SSEP HFOs were significantly reduced in MO patients between attacks, but enhanced during an attack. There was a positive correlation between degree of SAI and amplitude of early HFOs in HV, but not in MO or MI. When the two patient groups were pooled, both the MEP SAI slope and the SSEP habituation slope correlated positively with the number of days elapsed since the last migraine attack.Conclusions: The migraine cycle-dependent variations of SAI and SSEP HFOs are further evidence that facilitatory thalamocortical activation (of GABAergic networks in the motor cortex for SAI), likely to be cholinergic, is reduced in migraine at a distance from an attack, but increased ictally.

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