State Feedback Control Model Research Articles

Improving state feedback control model with deadband for reproducing human balancing motions

Improving state feedback control model with deadband for reproducing human balancing motions

Mechanisms of sensorimotor adaptation in a hierarchical state feedback control model of speech.

Upon perceiving sensory errors during movements, the human sensorimotor system updates future movements to compensate for the errors, a phenomenon called sensorimotor adaptation. One component of this adaptation is thought to be driven by sensory prediction errors-discrepancies between predicted and actual sensory feedback. However, the mechanisms by which prediction errors drive adaptation remain unclear. Here, auditory prediction error-based mechanisms involved in speech auditory-motor adaptation were examined via the feedback aware control of tasks in speech (FACTS) model. Consistent with theoretical perspectives in both non-speech and speech motor control, the hierarchical architecture of FACTS relies on both the higher-level task (vocal tract constrictions) as well as lower-level articulatory state representations. Importantly, FACTS also computes sensory prediction errors as a part of its state feedback control mechanism, a well-established framework in the field of motor control. We explored potential adaptation mechanisms and found that adaptive behavior was present only when prediction errors updated the articulatory-to-task state transformation. In contrast, designs in which prediction errors updated forward sensory prediction models alone did not generate adaptation. Thus, FACTS demonstrated that 1) prediction errors can drive adaptation through task-level updates, and 2) adaptation is likely driven by updates to task-level control rather than (only) to forward predictive models. Additionally, simulating adaptation with FACTS generated a number of important hypotheses regarding previously reported phenomena such as identifying the source(s) of incomplete adaptation and driving factor(s) for changes in the second formant frequency during adaptation to the first formant perturbation. The proposed model design paves the way for a hierarchical state feedback control framework to be examined in the context of sensorimotor adaptation in both speech and non-speech effector systems.

Decentralized control for interconnected semi-markovian jump systems with partially accessible transition rates: a dynamic memory event-triggered mechanism

This paper investigates the issue of decentralized control for interconnected semi-Markovian systems with partially accessible transition rates (TRs). Firstly, a dynamic system model with a memory event-triggered mechanism (METM) is designed, which can effectively improve the fault tolerance of the event-triggering mechanism by employing the historical trigger data. Then a state feedback control model with dynamic METM is constructed, in which the semi-Markovian parameters with completely unknown and partially known transition probabilities are considered. Some sufficient conditions that insure the stochastic stability of the interconnected semi-Markovian systems can be obtained by utilizing the Lyapunov function and suitable model transformations method. Meanwhile, the parameters and the controller gain matrices of dynamic METM are also solved simultaneously by applying the linear matrix inequalities (LMIs). Finally, a simulation example is given to verify the effectiveness of the proposed method.

Towards a New Model of Verbal Monitoring.

As all human activities, verbal communication is fraught with errors. It is estimated that humans produce around 16,000 words per day, but the word that is selected for production is not always correct and neither is the articulation always flawless. However, to facilitate communication, it is important to limit the number of errors. This is accomplished via the verbal monitoring mechanism. A body of research over the last century has uncovered a number of properties of the mechanisms at work during verbal monitoring. Over a dozen routes for verbal monitoring have been postulated. However, to date a complete account of verbal monitoring does not exist. In the current paper we first outline the properties of verbal monitoring that have been empirically demonstrated. This is followed by a discussion of current verbal monitoring models: the perceptual loop theory, conflict monitoring, the hierarchical state feedback control model, and the forward model theory. Each of these models is evaluated given empirical findings and theoretical considerations. We then outline lacunae of current theories, which we address with a proposal for a new model of verbal monitoring for production and perception, based on conflict monitoring models. Additionally, this novel model suggests a mechanism of how a detected error leads to a correction. The error resolution mechanism proposed in our new model is then tested in a computational model. Finally, we outline the advances and predictions of the model.

Modeling and control of mosquito-borne diseases with Wolbachia and insecticides

Mosquitoes cause more human suffering than any other organism. It is estimated that over one million people worldwide die from mosquito-borne diseases every year. With the continuous efforts of many researchers, Wolbachia gets more and more attention due to its characteristics of maternal transmission in mosquito population and it may cause cytoplasmic incompatibility (CI) which makes healthy females cannot fertilize normally after mating with infected males. In this paper, mathematical models are established to study Wolbachia transmission in mosquito population, and integrated mosquito control strategies are explored. Firstly, a classical ordinary differential system with general birth and death rate functions is established to describe the maternal transmission and CI effect. It is shown that the replacement strategy that the Wolbachia-uninfected mosquitoes are replaced by the infected ones is determined by the initial infection frequency. And Wolbachia spreads more easily for greater maternal transmission and CI rate. Moreover, all the wild mosquitoes will eventually be infected with Wolbachia if the maternal transmission is complete. Secondly, an impulsive state feedback control model is constructed to describe the integrated mosquito control. Besides Wolbachia, insecticides are sprayed when the quantity of mosquitoes reaches some Economic Threshold. The existence and stability of Wolbachia replacement periodic solution are discussed. Finally, some discussions are done and the future research directions are prospected.

A Lycaon pictus impulsive state feedback control model with Allee effect and continuous time delay

Allee effect (i.e. sparse effect) is active when the population density is small. Our purpose is to study such an effect of this phenomenon on population dynamics. We investigate an impulsive state feedback control single-population model with Allee effect and continuous delay. We first qualitatively analyze the singularity of this model. Then we obtain sufficient conditions for the existence of an order-one periodic orbit by the geometric theory of impulsive differential equations for the survival of endangered populations and obtain the uniqueness of an order-one periodic orbit by the monotonicity of the subsequent function. Furthermore, we prove the orbital asymptotic stability of an order-one periodic orbit using the geometric properties of successor functions to confirm the robustness of this control. Finally, we verify the correctness of our theoretical results by using some numerical simulations. Our results show that the release of artificial captive African wild dog (Lycaon pictus) can effectively protect the African wild dog population with Allee effect.

Evaluating the roles of left middle frontal gyrus in word production using electrocorticography

ABSTRACTTo assess the specific roles of left middle frontal gyrus (LMFG) in word production, electrocorticography signals were recorded from an epilepsy patient when he participated in language tasks. We found three sites of LMFG showed high-gamma perturbations with distinct patterns across tasks; and neural activities elicited in the same tasks shared similar patterns, while those elicited by stimuli leading to the same articulations did not. These findings confirmed that the LMFG takes active parts in word production, and suggested that it may serve as a temporal perceptual information storage space, supporting the hierarchical state feedback control model of word production.

A White-headed langurs impulsive state feedback control model with sparse effect and continuous delay

In this paper, a white-headed langurs impulsive state feedback control model with sparse effect and continuous delay is investigated. We get the sufficient condition under which the system has a unique order-1 periodic solution through the method of successor function, and prove the stability of the order-1 periodic solution by the limit method of the successor point sequences. Furthermore, we perform numerical analysis on the theoretical results. Our results show that artificial breeding andreleasing langurs in captive tothe wild can effectively protect wild white-headed langurs with sparse effect and continuous delay.

A pest management model with state feedback control

In this paper, research of a class of state feedback control model which is mainly used in crop pests management, with Bendixson-Dulac discriminance, proves that this model has an unique and globally stable positive equilibrium under the weak time-delay kernel function. Also, we adopt the subsequent function method in the ordinary differential equation of the geometric theory to prove that a sufficient condition holds for the existence of an order one period solution in the system. At the same time, it also proves that the periodic solution is asymptotically stable.

An impulsive state feedback control model for releasing white-headed langurs in captive to the wild

In this paper, an impulsive state feedback control model for releasing white-headed langurs in captive to the wild is investigated. By using the geometric theory of semi-continuous dynamic system, the method of successor functions and the analogue of the Poincare criterion, it is proved that under certain conditions the system has an order-1 periodic solution with trajectory asymptotical stability, and this periodic solution remains above some critical value. The theoretical results are verified by the numerical simulations. The conclusion is that simultaneously taking the measures of both population migration and artificial breeding can effectively protect wild white-headed langurs, so that the population can continue to survive and can avoid becoming extinct.

Auditory feedback control is involved at even sub-phonemic levels of speech production

In the target article, Hickok asserts that auditory and somatosensory feedback control operate at different levels in the speech production hierarchy, with somatosensory feedback control involved in lower-level phonemic processing and auditory feedback control involved in higher-level syllabic processing. This assertion is based in part on a characterization of phonemes as timeless feature bundles. In this commentary I argue that the linguistic conception of phonemes as timeless feature bundles is insufficient for characterizing the production of phonemes by the motor system, and I review evidence that auditory feedback control is used even at the sub-phonemic level of speech production, contrary to its role in the hierarchical state feedback control model.

The architecture of speech production and the role of the phoneme in speech processing

Speech production has been studied within a number of traditions including linguistics, psycholinguistics, motor control, neuropsychology and neuroscience. These traditions have had limited interaction, ostensibly because they target different levels of speech production or different dimensions such as representation, processing or implementation. However, closer examination of reveals a substantial convergence of ideas across the traditions and recent proposals have suggested that an integrated approach may help move the field forward. The present article reviews one such attempt at integration, the state feedback control (SFC) model and its descendent, the hierarchical SFC model. Also considered is how phoneme-level representations might fit in the context of the model.

Neural evidence for state feedback control of speaking

An important recent development in neuroscience has been the use of models based on state feedback control (SFC) to explain the role of the central nervous system in motor control. In SFC, control is based on internal feedback of an estimate of the dynamic state of the thing (e.g., arm) being controlled. Within the internal loop, the state is predicted from outgoing motor commands and corrected by comparing the feedback expected to result from this state with actual incoming sensory feedback. SFC has received scant attention in the speech community, but the indirect role it suggests for feedback can account for much of what is known about the role of feedback in speech motor control. Our lab has been investigating how well SFC also accounts for the neural correlates of auditory feedback processing during speaking. Our principal approach has used magnetoencephalography to record the cortical activity of speakers as they hear themselves speaking, but recently, we have also completed an auditory feedback study based on electrocorticography. Many of the results of these studies have supported the SFC model, but some have posed challenges for it, which will be discussed. [Work supported by NSF grant BCS-0926196 and NIH grant R01-DC010145.]

Computational neuroanatomy of speech production

Speech production has been studied predominantly from within two traditions, psycholinguistics and motor control. These traditions have rarely interacted, and the resulting chasm between these approaches seems to reflect a level of analysis difference: whereas motor control is concerned with lower-level articulatory control, psycholinguistics focuses on higher-level linguistic processing. However, closer examination of both approaches reveals a substantial convergence of ideas. The goal of this article is to integrate psycholinguistic and motor control approaches to speech production. The result of this synthesis is a neuroanatomically grounded, hierarchical state feedback control model of speech production.

Speech Production as State Feedback Control

Spoken language exists because of a remarkable neural process. Inside a speaker's brain, an intended message gives rise to neural signals activating the muscles of the vocal tract. The process is remarkable because these muscles are activated in just the right way that the vocal tract produces sounds a listener understands as the intended message. What is the best approach to understanding the neural substrate of this crucial motor control process? One of the key recent modeling developments in neuroscience has been the use of state feedback control (SFC) theory to explain the role of the CNS in motor control. SFC postulates that the CNS controls motor output by (1) estimating the current dynamic state of the thing (e.g., arm) being controlled, and (2) generating controls based on this estimated state. SFC has successfully predicted a great range of non-speech motor phenomena, but as yet has not received attention in the speech motor control community. Here, we review some of the key characteristics of speech motor control and what they say about the role of the CNS in the process. We then discuss prior efforts to model the role of CNS in speech motor control, and argue that these models have inherent limitations – limitations that are overcome by an SFC model of speech motor control which we describe. We conclude by discussing a plausible neural substrate of our model.

Static and dynamic state feedback control model of basal ganglia-thalamocortical loops.

It is argued that a novel control architecture, the Static and Dynamic State (SDS) feedback scheme, which utilizes speed-field tracking, exhibits global stability, and allows on-line tuning by any adaptation mechanism without canceling stability if certain structural conditions are met, can be viewed as a model of basal ganglia-thalamocortical loops since (1) the SDS scheme predicts the neuronal groups that fit neuronal classification in the supplementary motor area, the motor cortex and the putamen, (2) the structural stability conditions require parallel channels, a feature that these loops provide, and (3) the SDS scheme predicts two major disorders that can be identified as Parkinson's and Huntington's diseases. Simulations suggests that the basal ganglia work outside the realm of the stability condition allowed by the robustness of the scheme and required for increased computation speeds.

The functional states of the thalamus and the associated neuronal interplay.

The functional states of the thalamus and the associated neuronal interplay.