A two-motor centre-driven winder drive with a reduced switch count

2008 ◽  
Author(s):  
D. Dujic ◽  
M. Jones ◽  
E. Levi ◽  
S.N. Vukosavic
Keyword(s):  
Motor Centre

The nervous system of loligo ii. suboesophageal centres

1976 ◽  
Vol 274 (930) ◽  
pp. 101-167 ◽  
Keyword(s):  
Nervous System ◽  
Optic Lobe ◽  
Large Set ◽  
Eye Muscle ◽  
Branching Patterns ◽  
Control Centre ◽  
Jet Control ◽  
Motor Centre ◽  
Inputs And Outputs

A well-marked hierarchy of centres can be recognized within the suboesophageal lobes and ganglia of the arms. The inputs and outputs of each lobe are described. There are sets of motoneurons and intermediate motor centres, which can be activated either from the periphery or from above. They mostly do not send fibres up to the optic or higher motor centres. However, there is a large set of fibres running from the magnocellular lobe to all the basal supraoesophageal lobes. The centre for control of the four eye-muscle nerves in the anterior lateral pedal lobe receives many fibres direct from the statocyst and from the peduncle and basal lobes, but none direct from the optic lobe. The posterior lateral pedal is a backward continuation of the oculomotor centre, containing large cells that may be concerned in initiating attacks by the tentacles. An intermediate motor centre in the posterior pedal lobe probably controls steering. It sends fibres to the funnel and head retractors, and by both direct and interrupted pathways to the fin lobe. It receives fibres from the crista nerve and basal lobes, but none direct from the optic lobe. The jet control centre of the ventral magnocellular lobe receives fibres from the statocyst and skin and also from the optic and basal lobes. Some of these last also give extensive branches throughout the palliovisceral lobes. The branching patterns of the dendritic collaterals differ in the various lobes. Some estimates are given of the numbers of synaptic points. The dendritic collaterals of the motoneurons spread through large volumes of neuropil and they overlap. The incoming fibres spread widely and each presumably activates many motoneurons either together or serially. Many of the lobes contain numerous microneurons with short trunks restricted to the lobe, but there are none of these cells in the chromatophore lobes or fin lobes. The microneurons have only few dendritic collaterals, in contrast to the numerous ones on the nearby motoneurons.

scholarly journals Observations on reflex responses to rhythmical stimulation in the frog

1921 ◽  
Vol 92 (648) ◽  
pp. 328-341 ◽  
Keyword(s):  
Motor Nerve ◽  
Low Frequency ◽  
Point Of View ◽  
Spinal Reflex ◽  
Efferent Nerve ◽  
Spinal Motor ◽  
Primary Object ◽  
Functional Point ◽  
Motor Centre ◽  
Stimulation Of

The primary object of this investigation was the study of the relation between the frequency and intensity of stimulation, and the resulting reflex reactions. I first studied the effect of alteration of frequency at a given intensity of stimulation and found that under these conditions the frequency has an optimal value. With moderate and rapid frequency stimuli there is also an optimal intensity value, though with those of low frequency this is not the case. It was also hoped that some light might be thrown on the mechanism of the spinal reflex centre by the comparison of the isometrically recorded reflex tetanus, with the tetanus obtained directly by stimulation of the efferent nerve at varying intensity and frequency of stimulation. In particular, an attempt was made to settle the question as to whether stimulation of a nerve can set into action the whole of the reflex centre to which it is afferent. Camis (4) concluded that the cells of a spinal motor centre can be regarded from a functional point of view, as divided into several independent groups, though this division is not absolute. On the other hand, Dreyer and Sherrington’s (5) observations point rather to the physiological unity of the spinal motor centre; since they showed that the maximal mechanical power of tetanic contraction, obtainable from a muscle under spinal reflex action, is sometimes as great as that which can be evoked from it by direct faradisation of the motor nerve itself.

scholarly journals Nervous Control of Movement in Cephalopods

1960 ◽  
Vol 37 (1) ◽  
pp. 57-72 ◽  
Author(s):  
DONALD MELVIN WILSON
Keyword(s):  
Mechanical Response ◽  
Stellate Ganglion ◽  
Nervous Control ◽  
Absolute Refractory Period ◽  
Fast System ◽  
Mechanical Responses ◽  
Nerve Net ◽  
Nerve Muscle ◽  
Organizational Features ◽  
Motor Centre

1. Nerve muscle preparations have been made of the mantle and stellar nerves of octopuses and squids. 2. Two motor innervation systems have been found in each. Both have been observed as unit preparations. The possibility of double innervation of the same muscle cells exists but has not been directly checked. 3. The fast innervations produce electrical responses which are maximal to the first stimulus and which have little or no absolute refractory period. They appear to be local rather than spike potentials. Fatigue is very rapid. The mechanical response sums in Octopus, but not in Loligo. 4. The slow innervations produce electrical and mechanical responses which facilitate with repetition. The fast system of Loligo does likewise after fatigue to a low level of response. 5. No evidence was found for a functional nerve net in the mantle. 6. Organizational features of the stellate ganglion have been identified physiologically in MOctopus. The ganglion acts both as an integrating motor centre and as a reflex centre.

scholarly journals A RESEARCH UPON ANÆSTHESIA

1897 ◽  
Vol 2 (2) ◽  
pp. 131-150 ◽  
Author(s):  
H. C. Wood ◽  
Wm. S. Carter
Keyword(s):  
Blood Pressure ◽  
Respiratory Failure ◽  
Arterial Pressure ◽  
Respiratory Depression ◽  
Clinical Observation ◽  
Automatic Regulation ◽  
Direct Influence ◽  
Series Of Experiments ◽  
The Subject ◽  
Motor Centre

The conclusions which have been reached by the series of experiments recorded in the present memoir are: First. Lowered arterial pressure has a comparatively feeble effect upon the respiration, but when the pressure falls sufficiently, respiratory depression does occur. Second. Even excessive lowering of blood pressure primarily stimulates the vaso-motor centre, the sensibility of the centre being evidently necessary to the automatic regulation of the circulation. Third. The circulation recovers itself more slowly after profound etherization than after a like chloroform narcosis. Fourth. It is possible for ether as well as chloroform to produce death some hours after the cessation of its administration, at a time when the cerebrum has long freed itself from distinct evidences of the narcotic, so that consciousness and intellectual action have been restored. In applying these conclusions to the subject of practical anæsthesia it is evident that the depression of the circulation produced by chloroform has effect upon the respiratory centres only when the pressure has fallen very low, and whilst it may be a factor in the production of respiratory failure during chloroformization, the failure must be chiefly due to the direct influence exercised by the drug upon the respiratory centres. Clinical experience shows that nausea and general depression are more pronounced after the use of ether than after the use of chloroform, a difference which is strongly insisted upon by the advocates of chloroform as an important agent in favor of that anæsthetic. Our research confirms clinical observation, and experimentally shows that the depression of the circulation produced by ether is more permanent than that caused by chloroform; the reason probably being the large amount of ether which is necessary to produce profound narcosis, with lowering of the arterial pressure; an amount so large that it can neither be burned up in the system nor yet eliminated in the time which would be necessary for the much smaller amount of chloroform to be gotten rid of after chloroformization.

scholarly journals Localisation of the vaso-motor centre

1923 ◽  
Vol 58 (2-3) ◽  
pp. 168-174 ◽  
Author(s):  
J. M. D. Scott ◽  
Ff. Roberts
Keyword(s):  
Motor Centre

scholarly journals Reflex fractionation of a muscle

1926 ◽  
Vol 100 (705) ◽  
pp. 448-462 ◽  
Keyword(s):  
Point Of View ◽  
Spinal Reflexes ◽  
Primary Circuit ◽  
Lumbar Region ◽  
Afferent Nerves ◽  
Functional Point ◽  
Deep Anaesthesia ◽  
Hip Flexor ◽  
A Current ◽  
Motor Centre

Studying spinal reflexes Camis (1) (1910) from observations on M. semitendinosus (cat) reached the conclusions that “ the cells of a spinal motor centre ca be regarded from a functional point of view as divided into several independent groups,” but that “such independence is however not absolute.” The present experiments pursue a like inquiry. That in a reflex evoked by weak excitation of the afferent nerve the resulting contraction of the muscle may involve a portion only of the muscle has common acceptance. Camis’s observations, however, employed maximal stimuli and yet the muscle evidenced fractional responses ; whereas later (3) Dreyer and one of us found, contrary to previous (4) experience, that reflex tetani in some instances activated the sum-total of the muscle. Both of these observations are confirmed by the present experiments. Method . The sample muscles taken have been a hip-flexor, tensor fasciœ femoris , a knee flexor, semitendinosus , and an ankle flexor, tibialis anticus . The preparation (cat) has been spinal, with cord transection, performed under deep anæsthesia, in the anterior lumbar region, prior to intereollicular decerebration, the anæsthesia being later relaxed. All other muscles of the limb except that one attached to the myograph have been paralysed by resection or nervesection. The limb has been securely fixed by steel drills clamped to the table. For exciting reflex contraction various afferent nerves, as cited below, of the ipsilateral limb have been stimulated by faradisation. The inductorium has been coreless and its primary circuit fed by a current of less than 0·2 amp. An optically recording myograph with isometric registration and of the pattern described in a previous paper (2) has been used.

A two-motor centre-driven winder drive fed by a five-leg voltage source inverter

2007 ◽  
Author(s):  
M. Jones ◽  
D. Dujic ◽  
E. Levi ◽  
M. Bebic ◽  
B. Jeftenic
Keyword(s):  
Voltage Source ◽  
Voltage Source Inverter ◽  
Motor Centre

scholarly journals NEUROMOTOR BASES OF THE ESCAPE BEHAVIOUR OF NASSA MUTABILIS

1989 ◽  
Vol 143 (1) ◽  
pp. 493-507 ◽  
Author(s):  
G. LEMMNITZ ◽  
H. SCHUPPE ◽  
H. G. WOLFF
Keyword(s):  
Electrical Stimulation ◽  
Intact Animal ◽  
Chemical Stimulus ◽  
Escape Behaviour ◽  
Escape Reaction ◽  
Pleural Ganglion ◽  
Preliminary Phase ◽  
Motor Centre ◽  
Sequence Of Movements ◽  
Stimulation Of

The complex sequence of movements in the escape behaviour of the snail Nassa mutabilis (L.) was described in detail and the neuromotor activity underlying the behaviour was investigated by extra- and intracellular recording. The escape reaction is triggered by a chemical stimulus to the animal's foot, in these experiments either application of KCl solution or contact with a starfish. It consists of a preliminary phase in which the shell tilts to its side, the actual locomotor phase, and a final righting movement. The snail performs leaps, in which the foot and the shell are repeatedly rotated with respect to one another. EMGs recorded from the columellar muscle during the escape reaction showed that bursts of potentials are coupled to the shell rotations. In the intact animal this burst activity ordinarily began 0.6 ± 0.3 s after stimulation with KCl. In an animal dissected for recording from the columellar nerve (which supplies the columellar muscle), KCl stimulation of the dorsum of the foot induced burstlike neuronal activity with a latency of 0.5 ± 0.3 s. The dorsal foot region, the site at which the escape reaction can be triggered, was found to be supplied by the posterior pedal nerves; electrical stimulation of these nerves elicited bursts in the columellar nerve. The left pleural ganglion, which is known to contain neurones that project into the columellar nerve, was also found to contain neurones responsive to KCl stimulation of the foot. These findings suggest that the left pleural ganglion contains a motor centre which is involved in control of activity of the columellar nerve, and is also active during the escape reaction.

Sign in / Sign up

Export Citation Format

Share Document