Movements and Motor Patterns of the Buccal Mass of Pleurobranchaea During Feeding, Regurgitation and Rejection

1982 ◽  
Vol 98 (1) ◽  
pp. 195-211
Author(s):  
ANDREW D. McCLELLAN
Keyword(s):  
Motor Activity ◽  
Motor Pattern ◽  
Pattern Generator ◽  
Behavioural Response ◽  
Rhythmic Movements ◽  
Motor Patterns ◽  
Jaw Muscles ◽  
Behavioural Responses ◽  
Buccal Mass ◽  
Different Types

Feeding, regurgitation, and rejection in the marine gastropod Pleurobranchaea all involve similar but not identical rhythmic movements of buccal mass structures such as the radula, jaws and lips. The part of the motor pattern which produces rhythmic radula movement, as recorded in the major external muscles of the buccal mass of behaving semi-intact preparations, was similar during the three different types of behaviour, suggesting that they share a common motor-pattern generator. Other parts of the motor pattern were only obviously different during the vomiting phase of regurgitation. Differences in the function and motor patterns of feeding and rejection are presumably accounted for by differences in the activity of muscles which could not be recorded from in this study (e.g. jaw muscles). A general conclusion is that buccal rhythms in gastropods cannot automatically be assumed to underlie feeding, and this is particularly true for dissected preparations which do not execute a clear behavioural response. It would be necessary either to record motor activity that is unique for a given behaviour, or to employ preparations which execute unambiguous behavioural responses.

Re-Examination of Presumed Feeding Motor Activity in the Isolated Nervous System of Pleurobranchaea

1982 ◽  
Vol 98 (1) ◽  
pp. 213-228
Author(s):  
ANDREW D. McCLELLAN
Keyword(s):  
Nervous System ◽  
Motor Activity ◽  
Root Activity ◽  
Neural Correlate ◽  
Motor Patterns ◽  
Nervous Systems ◽  
Behavioural Responses ◽  
Buccal Mass ◽  
Fast Rhythm

1. In most isolated gastropod nervous systems, presumed feeding motor patterns are thought to be represented by the alternating motor activity in buccal roots, which underlies rhythmic radula movement. Since this movement accompanies several types of behaviour in the gastropod Pleurobranchaea (McClellan, 1979, 1980, 1982), the presumed feeding motor activity in the isolated nervous system of this animal was re-examined in more detail. 2. Alternating buccal root activity was shown here to be associated with other types of behaviour besides feeding, and is, therefore, not sufficiently unique to serve as a ‘neural correlate’ for feeding in Pleurobranchaea and presumably other gastropods. 3. Unlike the isolated nervous systems of most gastropods, which generate only one buccal rhythm, that of Pleurobranchaea generates two different buccal motor patterns which alternate: (1) a slow ‘primary’ rhythm whose behavioural identity is unclear, and (2) brief periods of a relatively fast rhythm which underlie bouts of vomiting. 4. In general, a buccal rhythm generated by an isolated gastropod nervous system can only be assigned a function if there are features of the rhythm that are unique to only one of the several behavioural responses involving the buccal mass.

scholarly journals Feedforward discharges couple the singing central pattern generator and ventilation central pattern generator in the cricket abdominal central nervous system

2019 ◽  
Vol 205 (6) ◽  
pp. 881-895 ◽  
Author(s):  
Stefan Schöneich ◽  
Berthold Hedwig
Keyword(s):  
Motor Activity ◽  
Central Pattern Generator ◽  
Sensory Feedback ◽  
Motor Pattern ◽  
Pattern Generator ◽  
Abdominal Muscle ◽  
Excitatory Input ◽  
Intracellular Recordings ◽  
Motor Patterns ◽  
The Brain

Abstract We investigated the central nervous coordination between singing motor activity and abdominal ventilatory pumping in crickets. Fictive singing, with sensory feedback removed, was elicited by eserine-microinjection into the brain, and the motor activity underlying singing and abdominal ventilation was recorded with extracellular electrodes. During singing, expiratory abdominal muscle activity is tightly phase coupled to the chirping pattern. Occasional temporary desynchronization of the two motor patterns indicate discrete central pattern generator (CPG) networks that can operate independently. Intracellular recordings revealed a sub-threshold depolarization in phase with the ventilatory cycle in a singing-CPG interneuron, and in a ventilation-CPG interneuron an excitatory input in phase with each syllable of the chirps. Inhibitory synaptic inputs coupled to the syllables of the singing motor pattern were present in another ventilatory interneuron, which is not part of the ventilation-CPG. Our recordings suggest that the two centrally generated motor patterns are coordinated by reciprocal feedforward discharges from the singing-CPG to the ventilation-CPG and vice versa. Consequently, expiratory contraction of the abdomen usually occurs in phase with the chirps and ventilation accelerates during singing due to entrainment by the faster chirp cycle.

Principles of rhythmic motor pattern generation

1996 ◽  
Vol 76 (3) ◽  
pp. 687-717 ◽  
Author(s):  
E. Marder ◽  
R. L. Calabrese
Keyword(s):  
Motor Pattern ◽  
Pattern Generation ◽  
Rhythmic Movements ◽  
Motor Patterns ◽  
Nervous Systems ◽  
Cellular Processes ◽  
Rhythmic Motor ◽  
Computational Analyses ◽  
Motor Pattern Generation ◽  
Rhythmic Motor Pattern

Rhythmic movements are produced by central pattern-generating networks whose output is shaped by sensory and neuromodulatory inputs to allow the animal to adapt its movements to changing needs. This review discusses cellular, circuit, and computational analyses of the mechanisms underlying the generation of rhythmic movements in both invertebrate and vertebrate nervous systems. Attention is paid to exploring the mechanisms by which synaptic and cellular processes interact to play specific roles in shaping motor patterns and, consequently, movement.

Specific behavioural responses triggered by identified mechanosensory receptor cells in the apical field of the giant rotifer Asplanchna sieboldi.

1998 ◽  
Vol 201 (2) ◽  
pp. 169-177
Author(s):  
K D Joanidopoulos ◽  
W Marwan
Keyword(s):  
Behavioural Response ◽  
Sensory Receptor ◽  
Receptor Specificity ◽  
Free Swimming ◽  
Behavioural Responses ◽  
Receptor Cells ◽  
Mechanical Interference ◽  
Different Types ◽  
Males And Females ◽  
Stimulation Of

The giant rotifer Asplanchna sieboldi swims by the propulsive effect of thousands of cilia arrayed in clusters around the apical field, which has several mechanosensory structures (sensilla) located at defined positions. Males and females differ in both their patterns of behaviour and their sensory receptor equipment. Unstimulated males swim straight with occasional spontaneous changes in direction until they hit an obstacle with their apical field. Depending on the direction and the strength of the mechanical interference, the animals show different behavioural responses. To analyse the effect of excitation of the apical mechanosensitive sensilla on these responses, males were held on microcapillaries, and the sensitivity of individual sensilla was assayed using micromanipulator-mediated mechanical stimulation. Stimulation of each of the four different types of sensillum triggered a specific and well-defined initial behavioural response. Individual animals behaved identically with respect to the receptor specificity of the responses. The behaviour of free-swimming males upon contact with obstacles or females is discussed on the basis of these results.

Fast Synaptic Connections From CBIs to Pattern-Generating Neurons in Aplysia: Initiation and Modification of Motor Programs

2003 ◽  
Vol 89 (4) ◽  
pp. 2120-2136 ◽  
Author(s):  
Itay Hurwitz ◽  
Irving Kupfermann ◽  
Klaudiusz R. Weiss
Keyword(s):  
Central Pattern Generator ◽  
Motor Pattern ◽  
Aplysia Californica ◽  
Pattern Generator ◽  
Synaptic Connections ◽  
Motor Patterns ◽  
Motor Programs ◽  
Postsynaptic Potentials ◽  
Buccal Ganglia ◽  
Very High

Consummatory feeding movements in Aplysia californica are organized by a central pattern generator (CPG) in the buccal ganglia. Buccal motor programs similar to those organized by the CPG are also initiated and controlled by the cerebro-buccal interneurons (CBIs), interneurons projecting from the cerebral to the buccal ganglia. To examine the mechanisms by which CBIs affect buccal motor programs, we have explored systematically the synaptic connections from three of the CBIs (CBI-1, CBI-2, CBI-3) to key buccal ganglia CPG neurons (B31/B32, B34, and B63). The CBIs were found to produce monosynaptic excitatory postsynaptic potentials (EPSPs) with both fast and slow components. In this report, we have characterized only the fast component. CBI-2 monosynaptically excites neurons B31/B32, B34, and B63, all of which can initiate motor programs when they are sufficiently stimulated. However, the ability of CBI-2 to initiate a program stems primarily from the excitation of B63. In B31/B32, the size of the EPSPs was relatively small and the threshold for excitation was very high. In addition, preventing firing in either B34 or B63 showed that only a block in B63 firing prevented CBI-2 from initiating programs in response to a brief stimulus. The connections from CBI-2 to the buccal ganglia neurons showed a prominent facilitation. The facilitation contributed to the ability of CBI-2 to initiate a BMP and also led to a change in the form of the BMP. The cholinergic blocker hexamethonium blocked the fast EPSPs induced by CBI-2 in buccal ganglia neurons and also blocked the EPSPs between a number of key CPG neurons within the buccal ganglia. CBI-2 and B63 were able to initiate motor patterns in hexamethonium, although the form of a motor pattern was changed, indicating that non-hexamethonium-sensitive receptors contribute to the ability of these cells to initiate bursts. By contrast to CBI-2, CBI-1 excited B63 but inhibited B34. CBI-3 excited B34 and not B63. The data indicate that CBI-1, -2, and -3 are components of a system that initiates and selects between buccal motor programs. Their behavioral function is likely to depend on which combination of CBIs and CPG elements are activated.

Canine small bowel motor patterns and contractions are not neurally regulated during enteric nutrient infusion

1998 ◽  
Vol 274 (5) ◽  
pp. G912-G922 ◽  
Author(s):  
Kevin E. Behrns ◽  
Michael G. Sarr ◽  
Russell B. Hanson ◽  
Alan R. Zinsmeister
Keyword(s):  
Small Bowel ◽  
Motor Activity ◽  
Motor Pattern ◽  
Motor Patterns ◽  
Motility Index ◽  
On Line ◽  
Increase Motor Activity ◽  
Extrinsic Innervation ◽  
Nutrient Infusion

The aims of this study were to determine the effects of duodenal and jejunoileal nutrient infusions on small intestinal motor patterns and intestinal contractions in neurally intact and neurally isolated small bowel. Fifteen dogs were prepared with duodenal and jejunal infusion and manometry catheters and a diverting jejunal cannula. Ten of the dogs underwent in situ neural isolation of the jejunoileum. A mixed nutrient meal (0.5 kcal/ml) was infused into the duodenum or jejunum at 3 ml/min for 5 h. Control experiments involved infusion of a balanced salt solution. Manometric data collected on-line to a microcomputer were analyzed for direction, distance, and velocity of spread of single pressure waves (SPW) and clustered contractions. Isolated duodenal and jejunoileal nutrient infusions inhibited the fasting motor pattern in neurally intact and neurally isolated small bowel. Motor activity (motility index) increased slightly during nutrient infusion within groups, but there were few differences between groups. Neither neural isolation nor nutrient infusion had a consistent effect on spread of SPW or migration of clustered contractions. Isolated duodenal and jejunoileal nutrient infusions in the dog inhibit fasting motor patterns and increase motor activity slightly but have little effect on characteristics of individual and clustered contractions. Extrinsic innervation to the jejunoileum or intrinsic neural continuity of the jejunum with the duodenum had little effect on single or grouped contractions. Although the changes in motor activity demonstrated in this study appear small, alterations in intestinal transit and absorption may still occur and may be of importance physiologically.

Evolution of air-breathing and central CO(2)/H(+) respiratory chemosensitivity: new insights from an old fish?

2000 ◽  
Vol 203 (22) ◽  
pp. 3505-3512 ◽  
Author(s):  
R.J. Wilson ◽  
M.B. Harris ◽  
J.E. Remmers ◽  
S.F. Perry
Keyword(s):  
Central Pattern Generator ◽  
Motor Pattern ◽  
Lung Ventilation ◽  
Pattern Generator ◽  
Motor Patterns ◽  
Air Breathing ◽  
Longnose Gar ◽  
Isolated Brainstem

While little is known of the origin of air-breathing in vertebrates, primitive air breathers can be found among extant lobe-finned (Sarcopterygii) and ray-finned (Actinopterygii) fish. The descendents of Sarcopterygii, the tetrapods, generate lung ventilation using a central pattern generator, the activity of which is modulated by central and peripheral CO(2)/H(+) chemoreception. Air-breathing in Actinopterygii, in contrast, has been considered a ‘reflexive’ behaviour with little evidence for central CO(2)/H(+) respiratory chemoreceptors. Here, we describe experiments using an in vitro brainstem preparation of a primitive air-breathing actinopterygian, the longnose gar Lepisosteus osseus. Our data suggest (i) that gill and air-breathing motor patterns can be produced autonomously by the isolated brainstem, and (ii) that the frequency of the air-breathing motor pattern is increased by hypercarbia. These results are the first evidence consistent with the presence of an air-breathing central pattern generator with central CO(2)/H(+) respiratory chemosensitivity in any primitive actinopterygian fish. We speculate that the origin of the central neuronal controller for air-breathing preceded the divergence of the sarcopterygian and actinopterygian lineages and dates back to a common air-breathing ancestor.

THEORETICAL ANALYSIS ON NEURAL OSCILLATOR TOWARD BIOMIMIC ROBOT CONTROL

2007 ◽  
Vol 04 (04) ◽  
pp. 697-715 ◽  
Author(s):  
DINGGUO ZHANG ◽  
KUANYI ZHU
Keyword(s):  
Theoretical Analysis ◽  
Robot Control ◽  
Piecewise Linear ◽  
Neural Oscillator ◽  
Robotic Control ◽  
Rhythmic Movements ◽  
Motor Patterns ◽  
Neural Oscillators ◽  
Different Types

Neural oscillator is derived from the central pattern generator (CPG) in the biological nervous system. It can generate motor patterns for the rhythmic movements. Neural oscillator is widely adopted in biomimic robot and humanoid robot for different types of rhythmic movement controls such as swimming and walking. Theoretical analysis about neural oscillator toward biomimic robot control is presented in this paper. The methods adopted here include stability theory, describing function, and piecewise linear analysis. Some important properties of the neural oscillator, such as the determination of frequency, oscillation, and stability, are exploited. Network property of multiple neural oscillators is also studied. The insightful results will strengthen the foundation of the neural oscillator and enhance its efficient application for robotic control purpose.

scholarly journals The central pattern generator underlying swimming in Dendronotus iris: a simple half-center network oscillator with a twist

2016 ◽  
Vol 116 (4) ◽  
pp. 1728-1742 ◽  
Author(s):  
Akira Sakurai ◽  
Paul S. Katz
Keyword(s):  
Central Pattern Generator ◽  
Body Wall ◽  
Impulse Activity ◽  
Motor Pattern ◽  
Pattern Generator ◽  
Excitatory Synapse ◽  
Dynamic Clamp ◽  
Motor Patterns ◽  
The Brain ◽  
Excitatory Drive

The nudibranch mollusc, Dendronotus iris, swims by rhythmically flexing its body from left to right. We identified a bilaterally represented interneuron, Si3, that provides strong excitatory drive to the previously identified Si2, forming a half-center oscillator, which functions as the central pattern generator (CPG) underlying swimming. As with Si2, Si3 inhibited its contralateral counterpart and exhibited rhythmic bursts in left-right alternation during the swim motor pattern. Si3 burst almost synchronously with the contralateral Si2 and was coactive with the efferent impulse activity in the contralateral body wall nerve. Perturbation of bursting in either Si3 or Si2 by current injection halted or phase-shifted the swim motor pattern, suggesting that they are both critical CPG members. Neither Si2 nor Si3 exhibited endogenous bursting properties when activated alone; activation of all four neurons was necessary to initiate and maintain the swim motor pattern. Si3 made a strong excitatory synapse onto the contralateral Si2 to which it is also electrically coupled. When Si3 was firing tonically but not exhibiting bursting, artificial enhancement of the Si3-to-Si2 synapse using dynamic clamp caused all four neurons to burst. In contrast, negation of the Si3-to-Si2 synapse by dynamic clamp blocked ongoing swim motor patterns. Together, these results suggest that the Dendronotus swim CPG is organized as a “twisted” half-center oscillator in which each “half” is composed of two excitatory-coupled neurons from both sides of the brain, each of which inhibits its contralateral counterpart. Consisting of only four neurons, this is perhaps the simplest known network oscillator for locomotion.

scholarly journals What Defines Different Modes of Snake Locomotion?

2020 ◽  
Vol 60 (1) ◽  
pp. 156-170 ◽  
Author(s):  
Bruce C Jayne
Keyword(s):  
Motor Pattern ◽  
Empirical Work ◽  
Current Data ◽  
The Body ◽  
Lateral Bending ◽  
Motor Patterns ◽  
Different Types ◽  
Lateral Undulation ◽  
Left And Right ◽  
Vertical Cylinders

Synopsis Animals move in diverse ways, as indicated in part by the wide variety of gaits and modes that have been described for vertebrate locomotion. Much variation in the gaits of limbed animals is associated with changing speed, whereas different modes of snake locomotion are often associated with moving on different surfaces. For several decades different types of snake locomotion have been categorized as one of four major modes: rectilinear, lateral undulation, sidewinding, and concertina. Recent empirical work shows that the scheme of four modes of snake locomotion is overly conservative. For example, during aquatic lateral undulation, the timing between muscle activity and lateral bending changes along the length of the snake, which is unlike terrestrial lateral undulation. The motor pattern used to prevent sagging while bridging gaps also suggests that arboreal lateral undulation on narrow surfaces or with a few discrete points of support has a different motor pattern than terrestrial lateral undulation when the entire length of the snake is supported. In all types of concertina locomotion, the distance from the head to the tail changes substantially as snakes alternately flex and then extend different portions of their body. However, snakes climbing cylinders with concertina exert forces medially to attain a purchase on the branch, whereas tunnels require pushing laterally to form an anchoring region. Furthermore, different motor patterns are used for these two types of concertina movement. Some snakes climb vertical cylinders with helical wrapping completely around the cylinder, whereas all other forms of concertina bend regions of the body alternately to the left and right. Current data support rectilinear locomotion and sidewinding as being distinct modes, whereas lateral undulation and concertina are best used for defining categories of gaits with some unifying similarities. Partly as a result of different motor patterns, I propose recognizing five and four distinct types of lateral undulation and concertina, respectively, resulting in a total of 11 distinct gaits previously recognized as only four.

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