We present an automatic denoising method based on the wavelet transform to obtain single trial evoked potentials. The method is based on the inter- and intra-scale variability of the wavelet coefficients and their deviations from baseline values. The performance of the method is tested with simulated event related potentials (ERPs) and with real visual and auditory ERPs. For the simulated data ...

purpose: to determine the clinical and paraclinical features of multiple sclerosis (ms) in patients presenting for the first time with optic neuritis. methods:  in this descriptive study, 35 patients with clinical evidence of optic neuritis were enrolled. our evaluation included a neurological examination, visual evoked potentials (vep), brainstem-auditory evoked potentials (baep), and brain mr...

Evoked Potentials are event-related activities that occurred as an electrical response from the brain to different sensory stimulations of nervous tissues. In this paper, auditory evoked potentials (AEP) brain responses were collected and examined. The data collection was done twice with three different levels of sound and frequencies. The auditory brain response data was extracted from the noi...

introduction: evoked potentials arisen by stimulating the brain can be utilized as a communication tool  between humans and machines. most brain-computer interface (bci) systems use the p300 component,  which is an evoked potential. in this paper, we evaluate the use of the hidden markov model (hmm) for  detection of p300.  materials and methods: the wavelet transforms, wavelet-enhanced indepen...

Introduction: Evoked potentials arisen by stimulating the brain can be utilized as a communication tool  between humans and machines. Most brain-computer interface (BCI) systems use the P300 component,  which is an evoked potential. In this paper, we evaluate the use of the hidden Markov model (HMM) for  detection of P300.  Materials and Methods: The wavelet transforms, wavelet-enhanced indepen...

Electroencephalograms (EEGs) are brain waves, which are recorded using scalp electrodes. Generally, signal attenuate on recording and amplitude of the evoked potentials (EPs) are low when merged with the base brain waves. Therefore, mathematical tools are needed to analysis the time series (EEGs) to discover the EPs in the base EEGs. This paper reviews spectral analysis based on periodic amplit...

  Effects of visual deprivation on the induction of epileptiform activity were studied in layer II/III of mature rat primary visual cortex. Field potentials were evoked by stimulation of layer IV in slices from control and dark-reared (OR) rats. Picrotoxin (PTX)-induced epileptic activity was characterized by spontaneous and evoked epileptic field potentials (EFPs). The results showed that OR s...

In the framework of the discussion about gamma (approx. 40 Hz) oscillations as information carriers in the brain, we investigated the relationship between gamma responses in the EEG and intersensory association. Auditory evoked potentials (AEPs) and visual evoked potentials (VEPs) were compared with bisensory evoked potentials (BEPs; simultaneous auditory and visual stimulation) in 15 subjects....

This paper presents a method for the estimation of Evoked Potentials (EP) using an aposreriori time varying filter based on Discrete Wavelet Transform (DWT). The proposed filter uses Alternate Subensemble Averaging (ASA) to arrive at the signal and noise scalogram estimates. This filter, when applied on the Ensemble Average @A), leads to an improvement in the S m When applied on the individual ...

This paper describes a method to reliably estimate latency of multifocal visual evoked potential (mfVEP) and a classifier to automatically separate reliable mfVEP traces from noisy traces. We also investigated which mfVEP peaks have reproducible latency across recording sessions. The proposed method performs cross-correlation between mfVEP traces and second order Gaussian wavelet kernels and me...