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This study developed upon the Mahar Doan and Boje simulations to create a novel pharmacokinetic/pharmacodynamic real-time compartmental model in Simulink. The model allowed for varying combinations of oral and intravenous drug dosing under steady and nonsteady-state endogenous transport inhibition methods. A joint pharmacodynamic model simulated an extracellular receptor binding process and an intracellular...
High-resolution time-frequency analyses of ictal EEG allow for identification and characterization of ictal patterns. These patterns reflect alterations in the brain network synchrony. It is not clear why seizures undergo these dynamical changes and what mechanisms contribute to or cause these changes. In this work we use neural modeling studies to address these issues. We investigate the role of...
A parameter estimation scheme for dynamic systems is employed to simultaneously estimate the states and parameters of the model of human cerebral blood flow velocity as a function of mean arterial blood pressure. The estimation results show 20-40% reduction in the output mean square error compared to that of the one obtained from the computer model addressed in a paper by Ticcks, et al. (1995). The...
The related studies have show that anxious disorder (AD) is associated with two factors: psychogenic and organic origin. In this study, using the functional magnetic resonance imaging (fMRI), we detect the responses in interrelated brain regions to different categories of auditory stimulation. The mathematic modeling was modeled according to the response data acquired, in order to study the correlative...
Computational modeling using GENESIS platform has led to advances in fabricating a model to test the influence of molecular/proteomic adaptations on behavior due to reward. The nucleus accumbens is an area of the brain that processes information from other parts of the brain and is an integral element of the 'reward pathway' in the brain. A simplified model of the accumbens using one neuron is developed...
We describe the calibration of a computer model of intracranial pressure (ICP) dynamics to correspond with annotated clinical data taken from a patient being treated for elevated ICP due to a traumatic brain injury. The research protocol employed during treatment includes adjusting the elevation of the head of the bed, adjusting the ventilator settings to induce mild hyperventilation and hypoventilation,...
This work presents an attempt to model a neural network functional design. In this design, both views of structural concept of brain reticular formation nature and psychological features are conjugated to give an instinctive behavior system that depends on two driving parameters of distance and threshold value. An experiment for interpreting the six primitive reactions of pattern recognition is conducted...
This paper demonstrates that a novel neural structure can be useful for formation of long-term memory. An essential core of the proposed model is a control signal for learning or memory formation, inspired by a possible biological learning mechanism observed in cerebral cortices and hippocampus. From a biological point of view, the control signal can be generated by the limbic system according to...
In this paper we present three related areas of research we are pursuing to study neural computation in vitro. Rat cortical neurons cultured on 60 channel multielectrode array (MEA) allow the researcher to measure from and stimulate sixty different sites across a small population of neurons grown in vitro. Using this system we can send stimulation patterns into the network and study how these living...
The capacity of the primary visual cortex (Vl) to extract salient contours from real black-and-white images is studied using a neural network model of information processing in V1. The model includes the input from the lateral geniculate nucleus, arranged according to the preferred orientation through a Gabor function, a feedforward inhibition from inhibitory interneurons and lateral connections (both...
This work presents the design of a mechanical vasoconstriction mechanism with application for cerebral autoregulation. The relationship between the applied voltage of a DC motor and the tension within a pressurized vessel wall was utilized for constricting an arteriole segment within an intracranial vascular model. Using current proportional to the string tension, options for closed loop feedback...
Functional brain imaging using MRI (functional MRI or fMRI) has become a valuable tool for studying function/structure relationships in the human brain in both normal and clinical populations. This paper describes the physiological changes associated with brain activity, including changes in blood flow, volume, and oxygenation. The latter of these, known as blood oxygenation level dependent (BOLD)...
The Circle of Willis (CoW) is a ring-like structure blood vessels at the base of the brain that distributes arterial blood to the cerebral mass. 1D and 3D CFD models of the Circle of Willis have been created to simulate clinical scenarios such as inclusions in afferent arteries and absent circulus vessels. Both models capture cerebral haemodynamic auto-regulation using proportional-integral controller...
This paper describes application of biologically realistic dynamic synapse neural networks on speech recognition task. The goal is to develop a noise-robust and feasible speech recognition system, based on fundamental functional principles of the brain. This task is accomplished in three steps: first speech signal is decomposed into different frequency bands. Second, short term energy of signals is...
The author assesses the validity of three models dealing with human arm trajectory control by evaluating their success in accounting for the kinematic characteristics of planar horizontal unconstrained point-to-point arm trajectories. These models are concerned with two significant issues. Namely, in what coordinate frame(s) are movements internally represented by the brain and, how intention is translated...
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