N. Pradhan

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Neural networks, inspired by the organizational principles of the human brain, have recently been used in various fields of application such as pattern recognition, identification, classification, speech, vision, signal processing, and control systems. In this study, a two-layered neural network has been trained for the recognition of temporal patterns of(More)
The dynamical behaviour of the brain is currently being viewed from the perspective of nonlinear dynamics. There are several reports of low dimensional chaotic activity in various states of human behaviour. The time evolution of chaotic systems exhibit many transitional states and brain is known to undergo a number of transitions in sleep. It evolves from(More)
Low dimensional chaos is a property of many physiological oscillatory systems including the brain. Time series of sleep EEG records have been analyzed in the framework of recent developments in nonlinear dynamics. One of the characteristics of a chaotic time series is its attractor dimension. The running attractor dimension of a chaotic time series may(More)
The EEG time series has been subjected to various formalisms of analysis to extract meaningful information regarding the underlying neural events. In this paper the linear prediction (LP) method has been used for analysis and presentation of spectral array data for the better visualisation of background EEG activity. It has also been used for signal(More)
PURPOSE Many opioid receptors are located in the same nuclei that are active in sleep regulation. It has been suggested that opioid peptides are involved in the induction of the sleep state. Prolonged opioid use has been hypothesized to cause disturbed sleep. It also causes excessive daytime sleepiness and fatigue. This study was conducted to compare the(More)
Running fractal dimensions were measured on four channels of an electroencephalogram (EEG) recorded from a normal volunteer. The changes in the background activity due to eye closure were clearly differentiated by the fractal method. The compressed spectral array (CSA) and the running fractal dimensions of the EEG showed corresponding changes with respect(More)
The developments in nonlinear dynamics and the theory of chaos have considerably altered our perception and analysis of many complex systems, including the brain. This paper reviews the physical and dynamical aspect of brain's electrical activity from this new perspective and indicates possible future directions. The importance of emerging trends of(More)
A young manic patient who showed poor response to lithium, neuroleptics and ECT and developed severe cxtrapyramidal side effects restricting the use of neuroleptics in high doses; showed marked clinical improvement with a combination of carbamazepine and lithium with sustained recovery. The case reported to illustrate the possible synergistic action(More)
A graphical display of the frequency content of background electroencephalogram (EEG) activity is obtained by calculating the spectral estimates using autocorrelation autoregressive method and the classical Fourier transform method. Display of spectral content of consecutive data segments is made using hidden-line suppression technique so as to get a(More)