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1.
Biophys J ; 123(2): 221-234, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38102827

RESUMO

Quantitative understanding of cellular processes, such as cell cycle and differentiation, is impeded by various forms of complexity ranging from myriad molecular players and their multilevel regulatory interactions, cellular evolution with multiple intermediate stages, lack of elucidation of cause-effect relationships among the many system players, and the computational complexity associated with the profusion of variables and parameters. In this paper, we present a modeling framework based on the cybernetic concept that biological regulation is inspired by objectives embedding rational strategies for dimension reduction, process stage specification through the system dynamics, and innovative causal association of regulatory events with the ability to predict the evolution of the dynamical system. The elementary step of the modeling strategy involves stage-specific objective functions that are computationally determined from experiments, augmented with dynamical network computations involving endpoint objective functions, mutual information, change-point detection, and maximal clique centrality. We demonstrate the power of the method through application to the mammalian cell cycle, which involves thousands of biomolecules engaged in signaling, transcription, and regulation. Starting with a fine-grained transcriptional description obtained from RNA sequencing measurements, we develop an initial model, which is then dynamically modeled using the cybernetic-inspired method, based on the strategies described above. The cybernetic-inspired method is able to distill the most significant interactions from a multitude of possibilities. In addition to capturing the complexity of regulatory processes in a mechanistically causal and stage-specific manner, we identify the functional network modules, including novel cell cycle stages. Our model is able to predict future cell cycles consistent with experimental measurements. We posit that this innovative framework has the promise to extend to the dynamics of other biological processes, with a potential to provide novel mechanistic insights.


Assuntos
Cibernética , Regulação da Expressão Gênica , Animais , Ciclo Celular/genética , Divisão Celular , Diferenciação Celular/genética , Modelos Biológicos , Mamíferos
2.
Pers Soc Psychol Rev ; 27(1): 3-27, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35440238

RESUMO

Value Fulfillment Theory (VFT) is a philosophical theory of well-being. Cybernetic Big Five Theory (CB5T) is a psychological theory of personality. Both start with a conception of the person as a goal-seeking (or value-pursuing) organism, and both take goals and the psychological integration of goals to be key to well-being. By joining VFT and CB5T, we produce a cybernetic value fulfillment theory in which we argue that well-being is best conceived as the fulfillment of psychologically integrated values. Well-being is the effective pursuit of a set of nonconflicting values that are emotionally, motivationally, and cognitively suitable to the person. The primary difference in our theory from other psychological theories of well-being is that it does not provide a list of intrinsic goods, instead emphasizing that each person may have their own list of intrinsic goods. We discuss the implications of our theory for measuring, researching, and improving well-being.


Assuntos
Cibernética , Personalidade , Humanos , Motivação , Transtornos da Personalidade , Teoria Psicológica
3.
J Pers ; 91(4): 1035-1050, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36536602

RESUMO

OBJECTIVE: According to Cybernetic Big Five Theory (CB5T), personality traits reflect variation in the parameters of evolved cybernetic mechanisms, and extreme manifestations of these traits correspond to a risk for psychopathology because they threaten the organism's ability to pursue its goals effectively. Our theory of autism as a consequence of low Plasticity extends CB5T to provide a cybernetic account of the origin of autistic traits. The theory argues that, because all psychological competencies are initially developed through exploration, typical development requires sensitivity to the incentive reward value of the unknown (i.e., the unpredicted). According to CB5T, motivation to explore the unknown is the core function underlying the metatrait Plasticity, the shared variance of Extraversion and Openness/Intellect. This theory makes predictions regarding the downstream developmental consequences of early low Plasticity, and each prediction maps well onto autistic symptomatology. METHOD: We surveyed 387 people. Measures included the Autism Quotient (AQ) scale and International Personality Item Pool items that are indicators of Plasticity and Stability. RESULTS: The association between AQ and Plasticity was ß = -.64. CONCLUSION: A strong negative correlation between Plasticity and AQ suggests ASD may be closely linked to a low sensitivity to the incentive reward value of the unknown.


Assuntos
Transtorno Autístico , Humanos , Transtorno Autístico/psicologia , Cibernética , Personalidade , Transtornos da Personalidade , Inquéritos e Questionários
4.
J Integr Neurosci ; 22(2): 39, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36992588

RESUMO

Norbert Wiener and Nikolai Bernstein set the stage for a worldwide multidisciplinary attempt to understand how purposive action is integrated with cognition in a circular, bidirectional manner, both in life sciences and engineering. Such a 'workshop' is still open and far away from a satisfactory level of understanding, despite the current hype surrounding Artificial Intelligence (AI). The problem is that Cognition is frequently confused with Intelligence, overlooking a crucial distinction: the type of cognition that is required of a cognitive agent to meet the challenge of adaptive behavior in a changing environment is Embodied Cognition, which is antithetical to the disembodied and dualistic nature of the current wave of AI. This essay is the perspective formulation of a cybernetic framework for the representation of actions that, following Bernstein, is focused on what has long been considered the fundamental issue underlying action and motor control, namely the degrees of freedom problem. In particular, the paper reviews a solution to this problem based on a model of ideomotor/muscle-less synergy formation, namely the Passive Motion Paradigm (PMP). Moreover, it is shown how this modeling approach can be reformulated in a distributed manner based on a self-organizing neural paradigm consisting of multiple topology-representing networks with attractor dynamics. The computational implication of such an approach is also briefly analyzed looking at possible alternatives of the von Neuman paradigm, namely neuromorphic and quantum computing, aiming in perspective at a hybrid computational framework for integrating digital information, analog information, and quantum information. It is also suggested that such a framework is crucial not only for the neurobiological modeling of motor cognition but also for the design of the cognitive architecture of autonomous robots of industry 4.0 that are supposed to interact and communicate naturally with human partners.


Assuntos
Inteligência Artificial , Cibernética , Humanos , Metodologias Computacionais , Teoria Quântica , Cognição
5.
BMC Med Educ ; 23(1): 657, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37691113

RESUMO

BACKGROUND: Class attendance is important for academic performance. Personal interactions between teachers and students are difficult in large classes; the number of medical undergraduate students in China ranges from dozens to over 100. It is important for teachers to control the teaching process to improve student attendance and participation. METHODS: Two classes of fourth-year undergraduate medical students, with each class comprising 115 students, participated in the study. One class, the trial group, was taught by the block-based teaching method based on cybernetics. This study was conducted with three of the courses in the Introduction to Oncology subject, and the trial group's courses included several blocks. Each block had a test paper that the students responded to immediately in class using the Internet. The teacher obtained feedback from the students when the rate of correct responses to block-test questions was less than 90%. The teacher adjusted the teaching in the following blocks according to the feedback information. The other class, the control group, was taught using the traditional lecture-based teaching method. RESULTS: The average attendance in the trial group was 104/115 (90.43%), and that in the control group was 83/115 (72.17%) (p = 0.0003). The teacher adjusted the teaching three times in the radiotherapy course owing to the complex ideas. After feedback, information on chemotherapy for the upper body was adjusted once, as was that on chemotherapy for the lower body, owing to students' attitudes. The average total score of the trial group was 86.06 ± 17.46 and that of the control group was 80.38 ± 6.97 (p = 0.041). Questionnaire I showed that the trial group students' attendance and participation were better than in the control group. Questionnaire II showed that the block-based teaching method based on cybernetics was approved by the students. CONCLUSIONS: The block-based teaching method based on cybernetics used in medical classes with large numbers of Chinese undergraduate students had positive effects.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Povo Asiático , Cibernética , População do Leste Asiático , Pessoal de Educação , Ensino , Educação de Graduação em Medicina/métodos , Avaliação Educacional
6.
Biol Cybern ; 116(4): 407-445, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35678918

RESUMO

Cancers are complex dynamic ecosystems. Reductionist approaches to science are inadequate in characterizing their self-organized patterns and collective emergent behaviors. Since current approaches to single-cell analysis in cancer systems rely primarily on single time-point multiomics, many of the temporal features and causal adaptive behaviors in cancer dynamics are vastly ignored. As such, tools and concepts from the interdisciplinary paradigm of complex systems theory are introduced herein to decode the cellular cybernetics of cancer differentiation dynamics and behavioral patterns. An intuition for the attractors and complex networks underlying cancer processes such as cell fate decision-making, multiscale pattern formation systems, and epigenetic state-transitions is developed. The applications of complex systems physics in paving targeted therapies and causal pattern discovery in precision oncology are discussed. Pediatric high-grade gliomas are discussed as a model-system to demonstrate that cancers are complex adaptive systems, in which the emergence and selection of heterogeneous cellular states and phenotypic plasticity are driven by complex multiscale network dynamics. In specific, pediatric glioblastoma (GBM) is used as a proof-of-concept model to illustrate the applications of the complex systems framework in understanding GBM cell fate decisions and decoding their adaptive cellular dynamics. The scope of these tools in forecasting cancer cell fate dynamics in the emerging field of computational oncology and patient-centered systems medicine is highlighted.


Assuntos
Cibernética , Glioblastoma , Criança , Ecossistema , Humanos , Modelos Biológicos , Medicina de Precisão
8.
J Med Philos ; 47(3): 387-406, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35926173

RESUMO

Although the term integration is central to the definition of brain death, there is little agreement on what it means. Through a genealogical analysis, this essay argues that there have been two primary ways of understanding integration in regard to organismal wholeness. One stems from neuroscience, focusing on the role of the brain in responding to external stimuli, which was taken up in phenomenological accounts of life. A second, arising out of cybernetics, focuses on the brain's role in homeostasis. Recent debates over brain death are largely over this cybernetic understanding of integration. However, the phenomenological understanding of organismal wholeness can be seen in arguments by the President's Council on Bioethics in favor of brain death. This essay argues that the cybernetic understanding of life is problematic and should be discarded. A phenomenological understanding of life can provide a better basis for arguments over definitions of life and death.


Assuntos
Bioética , Morte Encefálica , Encéfalo , Cibernética , Dissidências e Disputas , Humanos
9.
Biol Cybern ; 115(5): 431-438, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34633537

RESUMO

We celebrate the 60th anniversary of Biological Cybernetics. It has also been 30 years since "Self-organized control of bipedal locomotion by neural oscillators in unpredictable environment" was published in Biological Cybernetics (Taga et al. in Biol Cybern 65(3):147-159, 1991). I would like to look back on the creation of this paper and discuss its subsequent development and future perspectives.


Assuntos
Cibernética , Locomoção , Encéfalo , Estudos Prospectivos , Estudos Retrospectivos
10.
Proc Biol Sci ; 287(1928): 20200254, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32517625

RESUMO

A current evolutionary hypothesis predicts that the most extreme forms of animal weaponry arise in systems where combatants fight each other one-to-one, in duels. It has also been suggested that arms races in human interstate conflicts are more likely to escalate in cases where there are only two opponents. However, directly testing whether duels matter for weapon investment is difficult in animals and impossible in interstate conflicts. Here, we test whether superior combatants experience a disproportionate advantage in duels, as compared with multi-combatant skirmishes, in a system analogous to both animal and military contests: the battles fought by artificial intelligence agents in a computer war game. We found that combatants with experimentally improved fighting power had a large advantage in duels, but that this advantage deteriorated as the complexity of the battlefield was increased by the addition of further combatants. This pattern remained under the two different forms of the advantage granted to our focal artificial intelligence (AI) combatants, and became reversed when we switched the roles to feature a weak focal AI among strong opponents. Our results suggest that one-on-one combat may trigger arms races in diverse systems. These results corroborate the outcomes of studies of both animal and interstate contests, and suggest that elements of animal contest theory may be widely applicable to arms races generally.


Assuntos
Agressão , Comportamento Animal , Comportamento Competitivo , Animais , Inteligência Artificial , Evolução Biológica , Cibernética , Armas
11.
Semin Cell Dev Biol ; 50: 105-14, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26474540

RESUMO

The proinflammatory cytokine tumor necrosis factor (TNF) orchestrates complex multicellular processes through a wide variety of changes that it induces in cell functions. At various stages of the study of TNF, attention has been drawn to one of three different modes of its action. The work that led to the discovery of this cytokine addressed situations in which it inflicts massive damage to tissues through a mode of action that appeared to be unrestricted. In the years that followed, attention was drawn to the existence of negative feedback mechanisms that do restrict TNF formation and function, and of reciprocal mechanisms for negatively regulating TNF-induced gene activation and of cell death. Most recently, the discovery of the critical role of TNF in chronic inflammatory diseases directed attention to the ability of TNF also to act with no apparent time restriction. Major gaps still remain in our knowledge of the cellular and molecular basis for these three modes of TNF action.


Assuntos
Cibernética , Fator de Necrose Tumoral alfa/metabolismo , Animais , Endotoxinas/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais
12.
Biol Cybern ; 117(1-2): 1-3, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36947172
13.
Sensors (Basel) ; 18(7)2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29958442

RESUMO

This work develops a speech recognition system that uses two procedures of proposed noise detection and combined noise reduction. The system can be used in applications that require interactive robots to recognize the contents of speech that includes ambient noise. The system comprises two stages, which are the threshold-based noise detection and the noise reduction procedure. In the first stage, the proposed system automatically determines when to enhance the quality of speech based on the signal-to-noise ratio (SNR) values of the collected speech at all times. In the second stage, independent component analysis (ICA) and subspace speech enhancement (SSE) are employed for noise reduction. Experimental results reveal that the SNR values of the enhanced speech exceed those of the received noisy speech by approximately 20 dB to 25 dB. The noise reduction procedure improves the speech recognition rates by around 15% to 25%. The experimental results indicate that the proposed system can reduce the effect of noise in numerous noisy environments and improve the quality of speech for recognition purposes.


Assuntos
Ruído/prevenção & controle , Robótica/métodos , Razão Sinal-Ruído , Interface para o Reconhecimento da Fala , Fala , Biônica , Cibernética , Humanos
14.
Biol Cybern ; 110(2-3): 193-200, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27246170

RESUMO

Statistical properties of spike trains as well as other neurophysiological data suggest a number of mathematical models of neurons. These models range from entirely descriptive ones to those deduced from the properties of the real neurons. One of them, the diffusion leaky integrate-and-fire neuronal model, which is based on the Ornstein-Uhlenbeck (OU) stochastic process that is restricted by an absorbing barrier, can describe a wide range of neuronal activity in terms of its parameters. These parameters are readily associated with known physiological mechanisms. The other model is descriptive, Gamma renewal process, and its parameters only reflect the observed experimental data or assumed theoretical properties. Both of these commonly used models are related here. We show under which conditions the Gamma model is an output from the diffusion OU model. In some cases, we can see that the Gamma distribution is unrealistic to be achieved for the employed parameters of the OU process.


Assuntos
Difusão , Modelos Neurológicos , Neurônios , Cibernética , Processos Estocásticos
15.
Biol Cybern ; 110(2-3): 171-92, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27241189

RESUMO

Brain activity shows phase-amplitude coupling between its slow and fast oscillatory components. We study phase-amplitude coupling as recorded at individual sites, using a modified version of the well-known Wendling neural mass model. To the population of fast inhibitory interneurons of this model, we added external modulatory input and dynamic self-feedback. These two modifications together are sufficient to let the inhibitory population serve as a limit-cycle oscillator, with frequency characteristics comparable to the beta and gamma bands. The frequency and power of these oscillations can be tuned through the time constant of the dynamic and modulatory input. Alpha band activity is generated, as is usual in such models, as a result of interactions of pyramidal neurons and a population of slow inhibitory interneurons. The slow inhibitory population activity directly influences the fast oscillations via the synaptic gain between slow and fast inhibitory populations. As a result, the amplitude envelope of the fast oscillation is coupled to the phase of the slow activity; this result is consistent with the notion that phase-amplitude coupling is effectuated by interactions between inhibitory interneurons.


Assuntos
Interneurônios/fisiologia , Inibição Neural , Cibernética , Modelos Neurológicos , Células Piramidais/fisiologia
17.
Biol Cybern ; 110(2-3): 91-116, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27086133

RESUMO

In comparison with the high level of knowledge about vehicle dynamics which exists nowadays, the role of the driver in the driver-vehicle system is still relatively poorly understood. A large variety of driver models exist for various applications; however, few of them take account of the driver's sensory dynamics, and those that do are limited in their scope and accuracy. A review of the literature has been carried out to consolidate information from previous studies which may be useful when incorporating human sensory systems into the design of a driver model. This includes information on sensory dynamics, delays, thresholds and integration of multiple sensory stimuli. This review should provide a basis for further study into sensory perception during driving.


Assuntos
Condução de Veículo/psicologia , Cibernética , Humanos , Percepção/fisiologia
18.
Biol Cybern ; 110(2-3): 217-27, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27222110

RESUMO

This article provides an introductory overview of the state of research on Hierarchical Bayesian Modeling in cognitive development. First, a brief historical summary and a definition of hierarchies in Bayesian modeling are given. Subsequently, some model structures are described based on four examples in the literature. These are models for the development of the shape bias, for learning ontological kinds and causal schemata as well as for the categorization of objects. The Bayesian modeling approach is then compared with the connectionist and nativist modeling paradigms and considered in view of Marr's (1982) three description levels of information-processing mechanisms. In this context, psychologically plausible algorithms and ideas of their neural implementation are presented. In addition to criticism and limitations of the approach, research needs are identified.


Assuntos
Teorema de Bayes , Cognição/fisiologia , Algoritmos , Cibernética , Humanos , Aprendizagem
19.
Biol Cybern ; 110(2-3): 151-69, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27108135

RESUMO

We analyze a network of non-identical Rayleigh-van der Pol (RvdP) oscillators interconnected through either diffusive or nonlinear coupling functions. The work presented here extends existing results on the case of two nonlinearly coupled RvdP oscillators to the problem of considering a network of three or more of them. Specifically, we study synchronization and entrainment in networks of heterogeneous RvdP oscillators and contrast the effects of diffusive linear coupling strategies with the nonlinear Haken-Kelso-Bunz coupling, originally introduced to study human bimanual experiments. We show how convergence of the error among the nodes' trajectories toward a bounded region is possible with both linear and nonlinear coupling functions. Under the assumption that the network is connected, simple, and undirected, analytical results are obtained to prove boundedness of the error when the oscillators are coupled diffusively. All results are illustrated by way of numerical examples and compared with the experimental findings available in the literature on synchronization of people rocking chairs, confirming the effectiveness of the model we propose to capture some of the features of human group synchronization observed experimentally in the previous literature.


Assuntos
Simulação por Computador , Difusão , Dinâmica não Linear , Fatores de Tempo , Cibernética , Humanos
20.
Biol Cybern ; 110(2-3): 135-50, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27023096

RESUMO

Bayesian inference and bounded rational decision-making require the accumulation of evidence or utility, respectively, to transform a prior belief or strategy into a posterior probability distribution over hypotheses or actions. Crucially, this process cannot be simply realized by independent integrators, since the different hypotheses and actions also compete with each other. In continuous time, this competitive integration process can be described by a special case of the replicator equation. Here we investigate simple analog electric circuits that implement the underlying differential equation under the constraint that we only permit a limited set of building blocks that we regard as biologically interpretable, such as capacitors, resistors, voltage-dependent conductances and voltage- or current-controlled current and voltage sources. The appeal of these circuits is that they intrinsically perform normalization without requiring an explicit divisive normalization. However, even in idealized simulations, we find that these circuits are very sensitive to internal noise as they accumulate error over time. We discuss in how far neural circuits could implement these operations that might provide a generic competitive principle underlying both perception and action.


Assuntos
Teorema de Bayes , Simulação por Computador , Tomada de Decisões , Retroalimentação , Cibernética , Eletricidade , Percepção , Probabilidade
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