scholarly journals Robust Master-Slave Synchronization of Neuronal Systems

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Hector Puebla ◽  
Eliseo Hernández-Martínez ◽  
Mariana Rodriguez-Jara ◽  
Cesar S. Lopez-Monsalvo
Keyword(s):  
Simple Structure ◽  
Model Uncertainties ◽  
Physiological Mechanisms ◽  
Control Engineering ◽  
Living Organisms ◽  
Neuronal Systems ◽  
Stimulation Of Nerve ◽  
The Brain ◽  
Insight Into ◽  
Gaining Insight

The desire to understand physiological mechanisms of neuronal systems has led to the introduction of engineering concepts to explain how the brain works. The synchronization of neurons is a central topic in understanding the behavior of living organisms in neurosciences and has been addressed using concepts from control engineering. We introduce a simple and reliable robust synchronization approach for neuronal systems. The proposed synchronization method is based on a master-slave configuration in conjunction with a coupling input enhanced with compensation of model uncertainties. Our approach has two nice features for the synchronization of neuronal systems: (i) a simple structure that uses the minimum information and (ii) good robustness properties against model uncertainties and noise. Two benchmark neuronal systems, Hodgkin-Huxley and Hindmarsh-Rose neurons, are used to illustrate our findings. The proposed synchronization approach is aimed at gaining insight into the effect of external electrical stimulation of nerve cells.

scholarly journals Linear reinforcement learning in planning, grid fields, and cognitive control

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Payam Piray ◽  
Nathaniel D. Daw
Keyword(s):  
Decision Making ◽  
Reinforcement Learning ◽  
Cognitive Control ◽  
Linear Approximation ◽  
Nonlinear Model ◽  
Long Distance ◽  
Control Engineering ◽  
Future Events ◽  
The Brain ◽  
Insight Into

AbstractIt is thought that the brain’s judicious reuse of previous computation underlies our ability to plan flexibly, but also that inappropriate reuse gives rise to inflexibilities like habits and compulsion. Yet we lack a complete, realistic account of either. Building on control engineering, here we introduce a model for decision making in the brain that reuses a temporally abstracted map of future events to enable biologically-realistic, flexible choice at the expense of specific, quantifiable biases. It replaces the classic nonlinear, model-based optimization with a linear approximation that softly maximizes around (and is weakly biased toward) a default policy. This solution demonstrates connections between seemingly disparate phenomena across behavioral neuroscience, notably flexible replanning with biases and cognitive control. It also provides insight into how the brain can represent maps of long-distance contingencies stably and componentially, as in entorhinal response fields, and exploit them to guide choice even under changing goals.

scholarly journals Linear reinforcement learning: Flexible reuse of computation in planning, grid fields, and cognitive control

2019 ◽  
Author(s):  
Payam Piray ◽  
Nathaniel D. Daw
Keyword(s):  
Decision Making ◽  
Reinforcement Learning ◽  
Cognitive Control ◽  
Nonlinear Model ◽  
Long Distance ◽  
Control Engineering ◽  
Future Events ◽  
The Brain ◽  
Insight Into ◽  
Do So

AbstractIt is thought that the brain’s judicious allocation and reuse of computation underlies our ability to plan flexibly, but also failures to do so as in habits and compulsion. Yet we lack a complete, realistic account of either. Building on control engineering, we introduce a new model for decision making in the brain that reuses a temporally abstracted map of future events to enable biologically-realistic, flexible choice at the expense of specific, quantifiable biases. It replaces the classic nonlinear, model-based optimization with a linear approximation that softly maximizes around (and is weakly biased toward) a learned default policy. This solution exposes connections between seemingly disparate phenomena across behavioral neuroscience, notably flexible replanning with biases and cognitive control. It also gives new insight into how the brain can represent maps of long-distance contingencies stably and componentially, as in entorhinal response fields, and exploit them to guide choice even under changing goals.

scholarly journals Dynamic energy budget approaches for modelling organismal ageing

2010 ◽  
Vol 365 (1557) ◽  
pp. 3443-3454 ◽  
Author(s):  
Ingeborg M. M. van Leeuwen ◽  
Julio Vera ◽  
Olaf Wolkenhauer
Keyword(s):  
Energy Metabolism ◽  
Ageing Process ◽  
Energy Budgets ◽  
Wide Range ◽  
Wear And Tear ◽  
Strong Relation ◽  
Competing Causes ◽  
Living Organisms ◽  
Insight Into ◽  
Gaining Insight

Ageing is a complex multifactorial process involving a progressive physiological decline that, ultimately, leads to the death of an organism. It involves multiple changes in many components that play fundamental roles under healthy and pathological conditions. Simultaneously, every organism undergoes accumulative ‘wear and tear’ during its lifespan, which confounds the effects of the ageing process. The scenario is complicated even further by the presence of both age-dependent and age-independent competing causes of death. Various manipulations have been shown to interfere with the ageing process. Calorie restriction, for example, has been reported to increase the lifespan of a wide range of organisms, which suggests a strong relation between energy metabolism and ageing. Such a link is also supported within the main theories for ageing: the free radical hypothesis, for instance, links oxidative damage production directly to energy metabolism. The Dynamic Energy Budgets (DEB) theory, which characterizes the uptake and use of energy by living organisms, therefore constitutes a useful tool for gaining insight into the ageing process. Here we compare the existing DEB-based modelling approaches and, then, discuss how new biological evidence could be incorporated within a DEB framework.

Seeing the Brain in Action: How Multiphoton Imaging Has Advanced Our Understanding of Neuronal Function

2008 ◽  
Vol 14 (6) ◽  
pp. 482-491 ◽  
Author(s):  
Grace Stutzmann
Keyword(s):  
Brain Function ◽  
Structural Information ◽  
Multiphoton Microscopy ◽  
Biological Research ◽  
Neuronal Function ◽  
Multiphoton Imaging ◽  
New Era ◽  
The Brain ◽  
Insight Into ◽  
Gaining Insight

AbstractGaining insight into how the nervous system functions is a challenge for scientists, particularly because the static morphology of the brain and the cells within tell little about how they actually work. Fixed specimens can provide critical structural information, but the jump to functional neurobiology in living cells is obviated with these preparations. In order to grasp the complexity of neuronal activity, it is necessary to observe the brain in action, from the level of subcellular signaling to the whole organism. Recent advances in nonlinear microscopy have given rise to a new era for biological research. In particular, the introduction of multiphoton excitation has drastically improved the depth and speed to which we can probe brain function. In order to better appreciate recent contributions of multiphoton microscopy to our current and future understanding of biological systems, an historical awareness of past microscopy applications is useful.

From many to one: Meditation and the plasticity of the predictive mind

2020 ◽  
Author(s):  
Ruben Laukkonen ◽  
Heleen A Slagter
Keyword(s):  
Cognitive Enhancement ◽  
The Self ◽  
Predictive Processing ◽  
Focused Attention ◽  
Conceptual Processing ◽  
Current State ◽  
Contemplative Science ◽  
Open Monitoring ◽  
Living Organisms ◽  
The Brain

How profoundly can humans change their own minds? In this paper we offer a unifying account of meditation under the predictive processing view of living organisms. We start from relatively simple axioms. First, the brain is an organ that serves to predict based on past experience, both phylogenetic and ontogenetic. Second, meditation serves to bring one closer to the here and now by disengaging from anticipatory processes. We propose that practicing meditation therefore gradually reduces predictive processing, in particular counterfactual cognition—the tendency to construct abstract and temporally deep representations—until all conceptual processing falls away. Our Many- to-One account also places three main styles of meditation (focused attention, open monitoring, and non-dual meditation) on a single continuum, where each technique progressively relinquishes increasingly engrained habits of prediction, including the self. This deconstruction can also make the above processes available to introspection, permitting certain insights into one’s mind. Our review suggests that our framework is consistent with the current state of empirical and (neuro)phenomenological evidence in contemplative science, and is ultimately illuminating about the plasticity of the predictive mind. It also serves to highlight that contemplative science can fruitfully go beyond cognitive enhancement, attention, and emotion regulation, to its more traditional goal of removing past conditioning and creating conditions for potentially profound insights. Experimental rigor, neurophenomenology, and no-report paradigms combined with neuroimaging are needed to further our understanding of how different styles of meditation affect predictive processing and the self, and the plasticity of the predictive mind more generally.

EXPERIMENTAL ASSESSMENT OF THE NANOPARTICLES TOXICITY OF NICKEL OXIDE IN TWO SIZES IN THE SUBCHRONIC EXPERIMENT

2018 ◽  
pp. 30-35
Author(s):  
M.P. Sutunkova ◽  
B.A. Katsnelson ◽  
L.I. Privalova ◽  
S.N. Solovjeva ◽  
V.B. Gurvich ◽  
...  
Keyword(s):  
Nickel Oxide ◽  
Nervous Activity ◽  
Equal Mass ◽  
The Body ◽  
Subchronic Toxicity ◽  
Physiological Mechanisms ◽  
Nickel Oxide Nanoparticles ◽  
The Relationship ◽  
The Brain ◽  
Nanoparticles Toxicity

We conducted a comparative assessment of the nickel oxide nanoparticles toxicity (NiO) of two sizes (11 and 25 nm) according to a number of indicators of the body state after repeated intraperitoneal injections of these particles suspensions. At equal mass doses, NiO nanoparticles have been found to cause various manifestations of systemic subchronic toxicity with a particularly pronounced effect on liver, kidney function, the body’s antioxidant system, lipid metabolism, white and red blood, redox metabolism, spleen damage, and some disorders of nervous activity allegedly related to the possibility of nickel penetration into the brain from the blood. The relationship between the diameter and toxicity of particles is ambiguous, which may be due to differences in toxicokinetics, which is controlled by both physiological mechanisms and direct penetration of nanoparticles through biological barriers and, finally, unequal solubility.

Standing up to the Demos

2018 ◽  
Author(s):  
Andrew Erskine
Keyword(s):  
Athenian Democracy ◽  
Parallel Lives ◽  
Standing Up ◽  
A Minor ◽  
Insight Into ◽  
Gaining Insight ◽  
The Way

Plutarch wrote twenty-three Greek Lives in his series of Parallel Lives—of these, ten were devoted to Athenians. Since Plutarch shared the hostile view of democracy of Polybius and other Hellenistic Greeks, this Athenian preponderance could have been a problem for him. But Plutarch uses these men’s handling of the democracy and especially the demos as a way of gaining insight into the character and capability of his protagonists. This chapter reviews Plutarch’s attitude to Athenian democracy and examines the way a statesman’s character is illuminated by his interaction with the demos. It also considers what it was about Phocion that so appealed to Plutarch, first by looking at his relationship with the democracy and then at the way he evokes the memory of Socrates. For him this was not a minor figure, but a man whose life was representative of the problems of Athenian democracy.

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