Invited Review: Neuroplasticity in respiratory motor control

2003 ◽  
Vol 94 (1) ◽  
pp. 358-374 ◽  
Author(s):  
Gordon S. Mitchell ◽  
Stephen M. Johnson
Keyword(s):  
Control System ◽  
Neural Control ◽  
Developmental Plasticity ◽  
Biological Significance ◽  
Respiratory Control ◽  
System A ◽  
Cord Injury ◽  
Respiratory Plasticity ◽  
Considerable Work ◽  
Respiratory Gases

Although recent evidence demonstrates considerable neuroplasticity in the respiratory control system, a comprehensive conceptual framework is lacking. Our goals in this review are to define plasticity (and related neural properties) as it pertains to respiratory control and to discuss potential sites, mechanisms, and known categories of respiratory plasticity. Respiratory plasticity is defined as a persistent change in the neural control system based on prior experience. Plasticity may involve structural and/or functional alterations (most commonly both) and can arise from multiple cellular/synaptic mechanisms at different sites in the respiratory control system. Respiratory neuroplasticity is critically dependent on the establishment of necessary preconditions, the stimulus paradigm, the balance between opposing modulatory systems, age, gender, and genetics. Respiratory plasticity can be induced by hypoxia, hypercapnia, exercise, injury, stress, and pharmacological interventions or conditioning and occurs during development as well as in adults. Developmental plasticity is induced by experiences (e.g., altered respiratory gases) during sensitive developmental periods, thereby altering mature respiratory control. The same experience later in life has little or no effect. In adults, neuromodulation plays a prominent role in several forms of respiratory plasticity. For example, serotonergic modulation is thought to initiate and/or maintain respiratory plasticity following intermittent hypoxia, repeated hypercapnic exercise, spinal sensory denervation, spinal cord injury, and at least some conditioned reflexes. Considerable work is necessary before we fully appreciate the biological significance of respiratory plasticity, its underlying cellular/molecular and network mechanisms, and the potential to harness respiratory plasticity as a therapeutic tool.

Adaptation in the respiratory control system

2003 ◽  
Vol 81 (8) ◽  
pp. 765-773 ◽  
Author(s):  
James Duffin ◽  
Safraaz Mahamed
Keyword(s):  
Experimental Data ◽  
Control System ◽  
Steady State ◽  
Graphical Model ◽  
Respiratory Control ◽  
Ventilatory Responses ◽  
System A ◽  
Hypoxia Adaptation ◽  
Peripheral Chemoreflex

Exposure to hypoxia, whether for short or prolonged periods or for repeated episodes, produces alterations in the ventilatory responses. This review presents evidence that these adaptations are likely to be mediated by adaptations in the respiratory chemoreflexes, particularly the peripheral chemoreflex, and proposes models of respiratory control explaining the observed changes in ventilation. After a brief introduction to the respiratory control system, a graphical model is developed that illustrates the operation of the system in the steady state, which will be used later. Next, the adaptations in ventilatory responses to hypoxia that have been observed are described, and methods of measuring the alterations in the chemoreflexes that might account for them are discussed. Finally, experimental data supporting the view that changes in the activity of the peripheral chemoreflex can account for the ventilatory adaptations to hypoxia are presented and incorporated into models of chemoreflex behaviour during exposures to hypoxia of various durations.Key words: respiration, chemoreflexes, hypoxia, adaptation, models.

scholarly journals Intermittent reductions in respiratory neural activity elicit spinal TNF-α-independent, atypical PKC-dependent inactivity-induced phrenic motor facilitation

2015 ◽  
Vol 308 (8) ◽  
pp. R700-R707 ◽  
Author(s):  
Nathan A. Baertsch ◽  
Tracy L. Baker-Herman
Keyword(s):  
Neural Activity ◽  
Respiratory Control ◽  
Cellular Mechanisms ◽  
Compensatory Mechanisms ◽  
Atypical Pkc ◽  
System A ◽  
Tnf Α ◽  
Respiratory Plasticity ◽  
Dependent Form ◽  
Novel Therapeutic Strategies

In many neural networks, mechanisms of compensatory plasticity respond to prolonged reductions in neural activity by increasing cellular excitability or synaptic strength. In the respiratory control system, a prolonged reduction in synaptic inputs to the phrenic motor pool elicits a TNF-α- and atypical PKC-dependent form of spinal plasticity known as inactivity-induced phrenic motor facilitation (iPMF). Although iPMF may be elicited by a prolonged reduction in respiratory neural activity, iPMF is more efficiently induced when reduced respiratory neural activity (neural apnea) occurs intermittently. Mechanisms giving rise to iPMF following intermittent neural apnea are unknown. The purpose of this study was to test the hypothesis that iPMF following intermittent reductions in respiratory neural activity requires spinal TNF-α and aPKC. Phrenic motor output was recorded in anesthetized and ventilated rats exposed to brief intermittent (5, ∼1.25 min), brief sustained (∼6.25 min), or prolonged sustained (30 min) neural apnea. iPMF was elicited following brief intermittent and prolonged sustained neural apnea, but not following brief sustained neural apnea. Unlike iPMF following prolonged neural apnea, spinal TNF-α was not required to initiate iPMF during intermittent neural apnea; however, aPKC was still required for its stabilization. These results suggest that different patterns of respiratory neural activity induce iPMF through distinct cellular mechanisms but ultimately converge on a similar downstream pathway. Understanding the diverse cellular mechanisms that give rise to inactivity-induced respiratory plasticity may lead to development of novel therapeutic strategies to treat devastating respiratory control disorders when endogenous compensatory mechanisms fail.

Invited Review: Developmental plasticity in respiratory control

2003 ◽  
Vol 94 (1) ◽  
pp. 375-389 ◽  
Author(s):  
John L. Carroll
Keyword(s):  
Control System ◽  
Critical Period ◽  
Developmental Plasticity ◽  
Time Window ◽  
Phenotypic Diversity ◽  
Acute Hypoxia ◽  
Respiratory Control ◽  
Developmental Trajectory ◽  
Critical Periods ◽  
Postnatal Maturation

Development of the mammalian respiratory control system begins early in gestation and does not achieve mature form until weeks or months after birth. A relatively long gestation and period of postnatal maturation allows for prolonged pre- and postnatal interactions with the environment, including experiences such as episodic or chronic hypoxia, hyperoxia, and drug or toxin exposures. Developmental plasticity occurs when such experiences, during critical periods of maturation, result in long-term alterations in the structure or function of the respiratory control neural network. A critical period is a time window during development devoted to structural and/or functional shaping of the neural systems subserving respiratory control. Experience during the critical period can disrupt and alter developmental trajectory, whereas the same experience before or after has little or no effect. One of the clearest examples to date is blunting of the adult ventilatory response to acute hypoxia challenge by early postnatal hyperoxia exposure in the newborn. Developmental plasticity in neural respiratory control development can occur at multiple sites during formation of brain stem neuronal networks and chemoafferent pathways, at multiple times during development, by multiple mechanisms. Past concepts of respiratory control system maturation as rigidly predetermined by a genetic blueprint have now yielded to a different view in which extremely complex interactions between genes, transcriptional factors, growth factors, and other gene products shape the respiratory control system, and experience plays a key role in guiding normal respiratory control development. Early-life experiences may also lead to maladaptive changes in respiratory control. Pathological conditions as well as normal phenotypic diversity in mature respiratory control may have their roots, at least in part, in developmental plasticity.

Evidence on Food Control System in Charitable Food Assistance System: A Systematic Scoping Review

2018 ◽  
Author(s):  
Sizwe Makhunga ◽  
Tivani P. Mashamba-Thompson ◽  
Mbuzeleni Hlongwa ◽  
Khumbulani W. Hlongwana
Keyword(s):  
Control System ◽  
Scoping Review ◽  
Food Assistance ◽  
Assistance System ◽  
Food Control ◽  
System A

Multi-layer controller with state-constraint: Vehicle lateral stability control based on fuzzy logic

2021 ◽  
pp. 095440702110142
Author(s):  
Neng Wan ◽  
Guangping Zeng ◽  
Chunguang Zhang ◽  
Dingqi Pan ◽  
Songtao Cai
Keyword(s):  
Control System ◽  
Integrated Control ◽  
State Constraint ◽  
Stability Control ◽  
Lateral Stability ◽  
System A ◽  
Velocity Reduction ◽  
Vehicle Velocity ◽  
Allowable Range ◽  
Simulation Results

This paper deals with a new state-constrained control (SCC) system of vehicle, which includes a multi-layer controller, in order to ensure the vehicle’s lateral stability and steering performance under complex environment. In this system, a new constraint control strategy with input and state constraints is applied to calculate the steady-state yaw moment. It ensures the vehicle lateral stability by tracking the desired yaw rate value and limiting the allowable range of the side slip. Through the linkage of the three-layer controller, the tire load is optimized and achieve minimal vehicle velocity reduction. The seven-degree-of-freedom (7-DOF) simulation model was established and simulated in MATLAB to evaluate the effect of the proposed controller. Through the analysis of the simulation results, compared with the traditional ESC and integrated control, it not only solves the problem of obvious velocity reduction, but also solves the problem of high cost and high hardware requirements in integrated control. The simulation results show that designed control system has better performance of path tracking and driving state, which is closer to the desired value. Through hardware-in-the-loop (HIL) practical experiments in two typical driving conditions, the effectiveness of the above proposed control system is further verified, which can improve the lateral stability and maneuverability of the vehicle.

scholarly journals Permanent diaphragmatic deficits and spontaneous respiratory plasticity in a mouse model of incomplete cervical spinal cord injury

2021 ◽  
Vol 284 ◽  
pp. 103568
Author(s):  
Pauline Michel-Flutot ◽  
Arnaud Mansart ◽  
Therese B. Deramaudt ◽  
Isley Jesus ◽  
Kun-Ze Lee ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Mouse Model ◽  
Cervical Spinal Cord ◽  
Cervical Spinal Cord Injury ◽  
Cord Injury ◽  
Respiratory Plasticity

scholarly journals Decentralized Optimization for a Novel Control Structure of HVAC System

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Shiqiang Wang ◽  
Jianchun Xing ◽  
Ziyan Jiang ◽  
Juelong Li
Keyword(s):  
Control System ◽  
Decentralized Control ◽  
Control Structure ◽  
Optimization Method ◽  
Labor Cost ◽  
Smart Device ◽  
Hvac System ◽  
Decentralized Optimization ◽  
System A ◽  
Novel Method

A decentralized control structure is introduced into the heating, ventilation, and air conditioning (HVAC) system to solve the high maintenance and labor cost problem in actual engineering. Based on this new control system, a decentralized optimization method is presented for sensor fault repair and optimal group control of HVAC equipment. Convergence property of the novel method is theoretically analyzed considering both convex and nonconvex systems with constraints. In this decentralized control system, traditional device is fitted with a control chip such that it becomes a smart device. The smart device can communicate and operate collaboratively with the other devices to accomplish some designated tasks. The effectiveness of the presented method is verified by simulations and hardware tests.

Sign in / Sign up

Export Citation Format

Share Document