The effects of N,N-dimethyltryptamine on electrically evoked potentials in the visual system of the cat and the interaction of selected neuroleptic agents with ~ethyi~yp~mine were studied. Dimethyltryptamine caused a doss-dependent decrease in the amplitude of the response evoked by stimulation of the optic chiasm as recorded in the lateral geniculate nucleus and the visual cortex. Dimethyltryp...

Fourier transform is applied to detect the direction of stripe noise before de-noising, which is advantageous for selecting the corresponding detail coefficients for threshold quantization after stationary wavelet transform. Depending on the direction of stripe noise, the corresponding detail coefficients contain stripe noise need to be removed, while retaining the approximate coefficients and ...

Objective: We present a new method to effectively remove ballistocardiogram artifacts (BAs) of electroencephalography (EEG), recorded inside a 1.5 T static magnetic field scanner, and conserve the time and frequency features of EEG activity. Methods: The BAs are approximated as deterministically chaotic dynamics. A wavelet-based nonlinear noise reduction (WNNR) method consisting of wavelet tran...

A wavelet domain nonlinear filtering method for improving the signal-to-noise ratio (SNR) of the evoked potentials (EP) is proposed. The method modifies the selective filtering technique proposed for edge detection in images by Xu et al. for the case of signals which require a smooth transition at the edge points. It identifies the significant features of a noisy signal based on the correlation...