The role of sensory inputs in insect flight motor pattern generation

The cercal system of crickets detects low-frequency air currents produced by approaching predators and self-generated air currents during singing, which may provide sensory feedback to the singing motor network. We analyzed the effect of cercal stimulation on singing motor pattern generation to reveal the response of a singing interneuron to predator-like signals and to elucidate the possible role of self-generated air currents during singing. In fictive singing males, we recorded an interneuron of the singing network while applying air currents to the cerci; additionally, we analyzed the effect of abolishing the cercal system in freely singing males. In fictively singing crickets, the effect of short air stimuli is either to terminate prematurely or to lengthen the interchirp interval, depending on their phase in the chirp cycle. Within our stimulation paradigm, air stimuli of different velocities and durations always elicited an inhibitory postsynaptic potential in the singing interneuron. Current injection in the singing interneuron elicited singing motor activity, even during the air current-evoked inhibitory input from the cercal pathway. The disruptive effects of air stimuli on the fictive singing pattern and the inhibitory response of the singing interneuron point toward the cercal system being involved in initiating avoidance responses in singing crickets, according to the established role of cerci in a predator escape pathway. After abolishing the activity of the cercal system, the timing of natural singing activity was not significantly altered. Our study provides no evidence that self-generated cercal sensory activity has a feedback function for singing motor pattern generation.

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The role of neuronal excitation and inhibition in the pre-Bötzinger complex on the cough reflex in the cat

Journal of Neurophysiology ◽

10.1152/jn.00108.2021 ◽

2021 ◽

Author(s):

Tabitha Y Shen ◽

Ivan Poliacek ◽

Melanie J. Rose ◽

Matthew Nicholas Musselwhite ◽

Zuzana Kotmanova ◽

...

Keyword(s):

Blood Pressure ◽

Respiratory Rate ◽

Receptor Antagonist ◽

Gabaa Receptor ◽

Motor Pattern ◽

Pattern Generation ◽

Neuronal Excitation ◽

Bötzinger Complex ◽

Motor Pattern Generation

Brainstem respiratory neuronal network significantly contributes to cough motor pattern generation. Neuronal populations in the pre-Bötzinger complex (PreBötC) represent a substantial component for respiratory rhythmogenesis. We studied the role of PreBötC neuronal excitation and inhibition on mechanically induced tracheobronchial cough in 15 spontaneously breathing, pentobarbital anesthetized adult cats (35 mg/kg i.v. initially). Neuronal excitation by unilateral microinjection of glutamate analog D,L-homocysteic acid resulted in mild reduction of cough abdominal electromyogram (EMG) amplitudes and very limited temporal changes of cough compared to effects on breathing (very high respiratory rate, high amplitude inspiratory bursts with a short inspiratory phase and tonic inspiratory motor component). Mean arterial blood pressure temporarily decreased. Blocking glutamate related neuronal excitation by bilateral microinjections of non-specific glutamate receptor antagonist kynurenic acid reduced cough inspiratory and expiratory EMG amplitude and shortened most cough temporal characteristics similarly to breathing temporal characteristics. Respiratory rate decreased and blood pressure temporarily increased. Limiting active neuronal inhibition by unilateral and bilateral microinjections of GABAA receptor antagonist gabazine resulted in lower cough number, reduced expiratory cough efforts, and prolongation of cough temporal features and breathing phases (with lower respiratory rate). The PreBötC is important for cough motor pattern generation. Excitatory glutamatergic neurotransmission in the PreBötC is involved in control of cough intensity and patterning. GABAA receptor related inhibition in the PreBötC strongly affects breathing and coughing phase durations in the same manner, as well as cough expiratory efforts. In conclusion, differences in effects on cough and breathing are consistent with separate control of these behaviors.

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The role of motor neuron intrinsic properties in leech heartbeat fictive motor pattern generation

Frontiers in Neuroscience ◽

10.3389/conf.fnins.2010.04.00090 ◽

2010 ◽

Vol 4 ◽

Author(s):

Calabrese Ronald

Keyword(s):

Motor Neuron ◽

Motor Pattern ◽

Pattern Generation ◽

Intrinsic Properties ◽

Motor Pattern Generation

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Principles of rhythmic motor pattern generation

Physiological Reviews ◽

10.1152/physrev.1996.76.3.687 ◽

1996 ◽

Vol 76 (3) ◽

pp. 687-717 ◽

Cited By ~ 765

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.

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Neurophysiological data regarding motor pattern generation in the medulla oblongata of toads

The Science of Nature ◽

10.1007/bf01189189 ◽

1984 ◽

Vol 71 (11) ◽

pp. 590-591 ◽

Cited By ~ 31

Author(s):

J. -P. Ewert ◽

E. Sch�rg-Pfeiffer ◽

A. Weerasuriya

Keyword(s):

Medulla Oblongata ◽

Motor Pattern ◽

Pattern Generation ◽

Neurophysiological Data ◽

Motor Pattern Generation

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Higher order neurons in buccal ganglia of Pleurobranchaea elicit vomiting motor activity

Journal of Neurophysiology ◽

10.1152/jn.1983.50.3.658 ◽

1983 ◽

Vol 50 (3) ◽

pp. 658-670 ◽

Cited By ~ 6

Author(s):

A. D. McClellan

Keyword(s):

High Frequency ◽

Motor Pattern ◽

Higher Order ◽

Root Activity ◽

Command Neurons ◽

Sensory Inputs ◽

Buccal Ganglia ◽

Output Pattern ◽

Stimulation Of

The buccal mass of the gastropod Pleurobranchaea is used during a regurgitation response that consists of a writhing phase interrupted by brief periodic bouts of a vomiting phase (17, 20). During transitions from writhing to vomiting, specific changes occur in the motor pattern (19, 20). Evidence is presented suggesting that at least some of the initiation or "command" neurons for vomiting reside in the buccal ganglia. The present paper examines the role of two candidate vomiting-initiation cells, the ventral white cells (VWC) and midganglionic cells (MC), in the buccal ganglia of isolated nervous systems. Stimulation of single VWCs activates a vomiting motor pattern, consisting in part of alternating buccal root activity. Furthermore, the VWCs fire in high-frequency bursts during episodes (i.e., bouts) of this same vomiting pattern. Mutual reexcitation between the VWCs and motor pattern generator (MPG) appears to produce the accelerated buildup and maintenance of vomiting rhythms. Brief stimulation of single MCs "triggers" bouts of a vomiting motor pattern, but the membrane potential of this cell is only modulated during this same pattern, at least in the isolated nervous system. It is proposed that in intact animals the MCs are activated by sensory inputs and briefly excite the VWC-MPG network, thereby turning on the mutual reexcitatory mechanism mentioned above and switching the output pattern. A general implication for gastropod research is that higher order neurons that activate buccal root activity cannot automatically be given the function of "feeding command neuron," as some cells clearly control other responses, such as vomiting.

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