Neural Control of Swimming in Nudipleura Molluscs

Swimming Behavior ◽

Neural Mechanisms ◽

The Other ◽

Neural Basis ◽

Tritonia Diomedea ◽

Pleurobranchaea Californica ◽

Sea Slugs ◽

This article compares the neural basis for swimming in sea slugs belonging to the Nudipleura clade of molluscs. There are two primary forms of swimming. One, dorsal/ventral (DV) body flexions, is typified by Tritonia diomedea and Pleurobranchaea californica. Although Tritonia and Pleurobranchaea evolved DV swimming independently, there are at least two homologous neurons in the central pattern generators (CPGs) underlying DV swimming in these species. Furthermore, both species have serotonergic neuromodulation of synaptic strength intrinsic to their CPGs. The other form of swimming is with alternating left/right (LR) body flexions. Melibe and Dendronotus belong to a clade of species that all swim with LR body flexions. Although the swimming behavior is homologous, their swim CPGs differ in both cellular composition and in the details of the neural mechanisms. Thus, similar behaviors have independently evolved through parallel use of homologous neurons, and homologous behaviors can be produced by different neural mechanisms.

Intersegmental Coordination of Walking Movements in Stick Insects

Journal of Neurophysiology ◽

10.1152/jn.00727.2004 ◽

2005 ◽

Vol 93 (3) ◽

pp. 1255-1265 ◽

Cited By ~ 33

Author(s):

Björn Ch. Ludwar ◽

Marie L. Göritz ◽

Joachim Schmidt

Keyword(s):

Motor Pattern ◽

Stick Insect ◽

Neural Mechanisms ◽

Chordotonal Organ ◽

Adjacent Segment ◽

Body Segments ◽

Stick Insects ◽

Pattern Generators ◽

Leg Movements

Locomotion requires the coordination of movements across body segments, which in walking animals is expressed as gaits. We studied the underlying neural mechanisms of this coordination in a semi-intact walking preparation of the stick insect Carausius morosus. During walking of a single front leg on a treadmill, leg motoneuron (MN) activity tonically increased and became rhythmically modulated in the ipsilateral deafferented and deefferented mesothoracic (middle leg) ganglion. The pattern of modulation was correlated with the front leg cycle and specific for a given MN pool, although it was not consistent with functional leg movements for all MN pools. In an isolated preparation of a pair of ganglia, where one ganglion was made rhythmically active by application of pilocarpine, we found no evidence for coupling between segmental central pattern generators (CPGs) that could account for the modulation of MN activity observed in the semi-intact walking preparation. However, a third preparation provided evidence that signals from the front leg's femoral chordotonal organ (fCO) influenced activity of ipsilateral MNs in the adjacent mesothoracic ganglion. These intersegmental signals could be partially responsible for the observed MN activity modulation during front leg walking. While afferent signals from a single walking front leg modulate the activity of MNs in the adjacent segment, additional afferent signals, local or from contralateral or posterior legs, might be necessary to produce the functional motor pattern observed in freely walking animals.

Pathophysiology of the lower urinary tract and CNS

Canadian Urological Association Journal ◽

10.5489/cuaj.708 ◽

2013 ◽

Vol 5 (5-S2) ◽

pp. 126

Author(s):

Christopher Chapple

Keyword(s):

Spinal Cord ◽

Central Nervous System ◽

Nervous System ◽

Urinary Tract ◽

Lower Urinary Tract ◽

Neural Control ◽

Neural Mechanisms ◽

The Other ◽

Bladder Function ◽

Lower Urinary

A number of aspects of neural control are potentially important inthe control of bladder function, including both sensory and motorand peripheral and central pathways. It is likely that a combinationof disorders of both central and peripheral neural mechanisms isimportant in the genesis of urgency and the other symptoms of theoveractive bladder (OAB). Given the number of potential pathwaysinvolved, potential pharmacologic targets for OAB exist in the CNS(central nervous system; cerebral cortex, midbrain, spinal cord)and periphery (LUT; lower urinary tract). Antimuscarinics are stillthe mainstay of OAB treatment, but there are also a number ofother potentially efficacious drugs that may also provide benefitagainst the neurologic components of OAB. This review discussesthe impact of neurological abnormalities on lower urinary tractsymptoms and the potential for treatments targeting these pathwaysto improve symptoms.

The neural bases of vertebrate motor behaviour through the lens of evolution

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2020.0521 ◽

2021 ◽

Vol 377 (1844) ◽

Cited By ~ 1

Author(s):

Shreyas M. Suryanarayana ◽

Brita Robertson ◽

Sten Grillner

Keyword(s):

Phylogenetic Position ◽

Neural Basis ◽

Theme Issue ◽

Systems Neuroscience ◽

Vertebrate Brain ◽

Primary Driver ◽

Neural Bases ◽

Pattern Generators ◽

Ancestral Vertebrate

The primary driver of the evolution of the vertebrate nervous system has been the necessity to move, along with the requirement of controlling the plethora of motor behavioural repertoires seen among the vast and diverse vertebrate species. Understanding the neural basis of motor control through the perspective of evolution, mandates thorough examinations of the nervous systems of species in critical phylogenetic positions. We present here, a broad review of studies on the neural motor infrastructure of the lamprey, a basal and ancient vertebrate, which enjoys a unique phylogenetic position as being an extant representative of the earliest group of vertebrates. From the central pattern generators in the spinal cord to the microcircuits of the pallial cortex, work on the lamprey brain over the years, has provided detailed insights into the basic organization (a bauplan ) of the ancestral vertebrate brain, and narrates a compelling account of common ancestry of fundamental aspects of the neural bases for motion control, maintained through half a billion years of vertebrate evolution. This article is part of the theme issue ‘Systems neuroscience through the lens of evolutionary theory’.

A simple CPG-based model to generate human hip moment pattern in walking by generating stiffness and equilibrium point trajectories

10.1101/737031 ◽

2019 ◽

Author(s):

Alireza Bahramian ◽

Farzad Towhidkhah ◽

Sajad Jafari

Keyword(s):

Equilibrium Point ◽

Swing Phase ◽

The Other ◽

Double Pendulum ◽

Basic Model ◽

Human Movements ◽

Co Activation ◽

Point Trajectories ◽

AbstractEquilibrium point hypothesis (its developed version named as referent control theory) presents a theory about how the central nerves system (CNS) generates human movements. On the other hand, it has been shown that nerves circuits known as central pattern generators (CPG) likely produce motor commands to the muscles in rhythmic motions. In the present study, we designed a bio-inspired walking model, by coupling double pendulum to CPGs that produces equilibrium and stiffness trajectories as reciprocal and co-activation commands. As a basic model, it is has been shown that this model can regenerate pattern of a hip moment in the swing phase by high correlation (ρ = 0.970) with experimental data. Moreover, it has been reported that a global electromyography (EMG) minima occurs in the mid-swing phase when the hip is more flexed in comparison with the other leg. Our model showed that equilibrium and actual hip angle trajectories match each other in mid-swing, similar to the mentioned posture, that is consistent with previous findings. Such a model can be used in active exoskeletons and prosthesis to make proper active stiffness and torque.

The Tritonia Swim Central Pattern Generator

Handbook of Brain Microcircuits ◽

10.1093/med/9780190636111.003.0051 ◽

2017 ◽

pp. 561-568

Author(s):

Paul S. Katz

Keyword(s):

Central Pattern Generator ◽

Sensory Feedback ◽

Pattern Generator ◽

Emergent Property ◽

The Other ◽

Entire Body ◽

Neural Basis ◽

Sea Slug ◽

Tritonia Diomedea ◽

State Dependent

Tritonia diomedea is a sea slug that escapes from predatory starfish by rhythmically flexing its entire body in the dorsal and ventral directions. This escape swim behavior is produced by a central pattern generator (CPG), without needing sensory feedback. There are several features of the neural basis for this response that make it of particular interest for neuroscientists. One is that the CPG is a network oscillator; bursting arises as an emergent property of the neurons and their connectivity. Another interesting feature is that the CPG contains state-dependent, intrinsic neuromodulation: one of the CPG neurons uses the neurotransmitter serotonin (5-HT) to modulate the strength of synapses made by the other CPG neurons under certain conditions. This CPG seems to have evolved from a nonoscillatory network. Finally, there are novel mechanisms for plasticity during learning and in response to injury.

A Bioinspired Gait Transition Model for a Hexapod Robot

Journal of Robotics ◽

10.1155/2018/2913636 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Qing Chang ◽

Fanghua Mei

Keyword(s):

High Speed ◽

Neural System ◽

Physical Experiment ◽

Neural Mechanisms ◽

Transition Model ◽

Hexapod Robot ◽

Gait Transition ◽

Proposed Model ◽

Inspired by the analysis of the ant locomotion observed by the high-speed camera, an ant-like gait transition model for the hexapod robot is proposed in this paper. The model which consists of the central neural system (CNS), neural network (NN), and central pattern generators (CPGs) can produce the rhythmic signals for different gaits and can realize the transition of these gait automatically and smoothly according to the change of terrain. The proposed model suggests the neural mechanisms of the ant gait transition and can improve the environmental adaptability of the hexapod robot. The numerical simulation and corresponding physical experiment are implemented in this paper to verify the proposed method.

Towards an Understanding of Control of Complex Rhythmical “Wavelike” Coordination in Humans

Brain Sciences ◽

10.3390/brainsci10040215 ◽

2020 ◽

Vol 10 (4) ◽

pp. 215

Author(s):

Ross Howard Sanders ◽

Daniel J. Levitin

Keyword(s):

Neural Control ◽

Future Research ◽

Front Crawl ◽

Screening Criteria ◽

Pattern Generators ◽

Complex Relationships ◽

Cns Control

How does the human neurophysiological system self-organize to achieve optimal phase relationships among joints and limbs, such as in the composite rhythms of butterfly and front crawl swimming, drumming, or dancing? We conducted a systematic review of literature relating to central nervous system (CNS) control of phase among joint/limbs in continuous rhythmic activities. SCOPUS and Web of Science were searched using keywords “Phase AND Rhythm AND Coordination”. This yielded 1039 matches from which 23 papers were extracted for inclusion based on screening criteria. The empirical evidence arising from in-vivo, fictive, in-vitro, and modelling of neural control in humans, other species, and robots indicates that the control of movement is facilitated and simplified by innervating muscle synergies by way of spinal central pattern generators (CPGs). These typically behave like oscillators enabling stable repetition across cycles of movements. This approach provides a foundation to guide the design of empirical research in human swimming and other limb independent activities. For example, future research could be conducted to explore whether the Saltiel two-layer CPG model to explain locomotion in cats might also explain the complex relationships among the cyclical motions in human swimming.

Bringing up the rear: new premotor interneurons add regional complexity to a segmentally distributed motor pattern

Journal of Neurophysiology ◽

10.1152/jn.00519.2011 ◽

2011 ◽

Vol 106 (5) ◽

pp. 2201-2215 ◽

Cited By ~ 9

Author(s):

Angela Wenning ◽

Brian J. Norris ◽

Anca Doloc-Mihu ◽

Ronald L. Calabrese

Keyword(s):

Phase Difference ◽

Motor Neurons ◽

Regional Difference ◽

Motor Pattern ◽

The Other ◽

The Core ◽

Asymmetric Pattern ◽

Pattern Generators ◽

Two Sides

Central pattern generators (CPGs) pace and pattern many rhythmic activities. We have uncovered a new module in the heartbeat CPG of leeches that creates a regional difference in this segmentally distributed motor pattern. The core CPG consists of seven identified pairs and one unidentified pair of heart interneurons of which 5 pairs are premotor and inhibit 16 pairs of heart motor neurons. The heartbeat CPG produces a side-to-side asymmetric pattern of activity of the premotor heart interneurons corresponding to an asymmetric fictive motor pattern and an asymmetric constriction pattern of the hearts with regular switches between the two sides. The premotor pattern progresses from rear to front on one side and nearly synchronously on the other; the motor pattern shows corresponding intersegmental coordination, but only from segment 15 forward. In the rearmost segments the fictive motor pattern and the constriction pattern progress from front to rear on both sides and converge in phase. Modeling studies suggested that the known inhibitory inputs to the rearmost heart motor neurons were insufficient to account for this activity. We therefore reexamined the constriction pattern of intact leeches. We also identified electrophysiologically two additional pairs of heart interneurons in the rear. These new heart interneurons make inhibitory connections with the rear heart motor neurons, are coordinated with the core heartbeat CPG, and are dye-coupled to their contralateral homologs. Their strong inhibitory connections with the rearmost heart motor neurons and the small side-to-side phase difference of their bursting contribute to the different motor and beating pattern observed in the animal's rear.

SENSORY FEEDBACK IN CNN-BASED CENTRAL PATTERN GENERATORS

International Journal of Neural Systems ◽

10.1142/s0129065703001698 ◽

2003 ◽

Vol 13 (06) ◽

pp. 469-478 ◽

Cited By ~ 19

Author(s):

PAOLO ARENA ◽

LUIGI FORTUNA ◽

MATTIA FRASCA ◽

LUCA PATANÉ

Keyword(s):

Nonlinear Systems ◽

Motor Neurons ◽

Sensory Feedback ◽

Dynamic Properties ◽

The Other ◽

Walking Robots ◽

Hexapod Robot ◽

Local Bifurcations ◽

Central Pattern Generators (CPGs) are a suitable paradigm to solve the problem of locomotion control in walking robots. CPGs are able to generate feed-forward signals to achieve a proper coordination among the robot legs. In literature they are often modelled as networks of coupled nonlinear systems. However the topic of feedback in these systems is rarely addressed. On the other hand feedback is essential for locomotion. In this paper the CPG for a hexapod robot is implemented through Cellular Neural Networks (CNNs). Feedback is included in the CPG controller by exploiting the dynamic properties of the CPG motor-neurons, such as synchronization issue and local bifurcations. These universal paradigms provide the essential issues to include sensory feedback in CPG architectures based on coupled nonlinear systems. Experiments on a dynamic model of a hexapod robot are presented to validate the approach introduced.

Towards an Understanding of Control of Complex Rhythmical ‘Wavelike’ Coordination in Humans

10.20944/preprints202002.0340.v1 ◽

2020 ◽

Author(s):

Ross Howard Sanders ◽

Daniel J. Levitin

Keyword(s):

Neural Control ◽

Future Research ◽

Front Crawl ◽

Screening Criteria ◽

Pattern Generators ◽

Complex Relationships ◽

Cns Control

How does the human neurophysiological system self-organize to achieve optimal phase relationships among joints and limbs, such as in the composite rhythms of butterfly and front crawl swimming, drumming, or dancing? We conducted a systematic review of literature relating to CNS control of phase among joint/limbs in continuous rhythmic activities. SCOPUS and Web of Science were searched using keywords ‘Phase AND Rhythm AND Coordination’. This yielded 998 matches from which 23 papers were extracted for inclusion based on screening criteria. The empirical evidence arising from in-vivo, fictive, in-vitro, and modelling of neural control in humans, other species, and robots indicates that the control of movement is facilitated and simplified by innervating muscle synergies by way of spinal central pattern generators (CPGs). These typically behave like oscillators enabling stable repetition across cycles of movements. This approach provides a foundation to guide the design of empirical research in human swimming and other limb independent activities. For example, future research could be conducted to explore whether the two-layer CPG model proposed by Saltiel et al [1] to explain locomotion in cats might also explain the complex relationships among the cyclical motions in human swimming.