background and objective: vep is a powerful method to study visual system via evaluating evoked potentials. technologic and instrumental restrictions may be the reason of having studies on optical modulation and induction such as color, spatial frequency and contrast. developments of computer software and hardware may lead to an increase in the flexibility of pattern designs. material and meth...

The curve of visual evoked potentials was observed and compared with changes of visual acuity and visual field during a 24-month period in a group of 39 patients with optic nerve injury as a result of mild cerebral trauma. Results of the study showed great improvement of visual acuity and visual field after treatment, and slower and continuous improvement of visual evoked potentials. The main a...

In this paper, we propose a hybrid video coder using the wavelet packet transform and motion compensation. To reduce the computational complexity of the wavelet packet decomposition, a novel criterion based on the rate-distortion function is proposed. After the wavelet packet transform, the successive quantization scheme and the adaptive arithmetic coder are applied for lossy wavelet coe cient ...

Background: Alzheimer dementia as the most common cause of dementia is a chronic, progressive, irreversible and incurable disease. The second most common cause of dementia after Alzheimer is vascular dementia. One of the systems involved in dementia is the visuospatial system and visual evoked potential (VEP) can be one of the diagnostic methods for this disease. Therefore, the present study ai...

The present study aimed at examining the event-related potentials (ERPs) single-trial extraction during an emotional processing by wavelet transform and analyzing the brain responses to emotional stimuli. ERPs were recorded from 64 electrodes in 10 healthy university students while three types of emotional pictures (pleasant, neural, and unpleasant) from the international affective picture syst...

Introduction: An efficient method of tomographic imaging in nuclear medicine is positron emission tomography (PET). Compared to SPECT, PET has the advantages of higher levels of sensitivity, spatial resolution and more accurate quantification. However, high noise levels in the image limit its diagnostic utility. Noise removal in nuclear medicine is traditionally based on Fourier decomposition o...

the objective of this study is development of driver’s sleepiness using visually evoked potentials (vep). vep computed from eeg signals from the visual cortex. we use the steady state veps (ssveps) that are one of the most important eeg signals used in human computer interface systems. ssvep is a response to visual stimuli presented. we present a classification method to discriminate between cl...

OBJECTIVE This study aims (1) to develop an automated and fast approach for detecting visual evoked potentials (VEPs) in single trials and (2) to apply the single-trial VEP detection approach in designing a real-time and high-performance brain-computer interface (BCI) system. METHODS The single-trial VEP detection approach uses common spatial pattern (CSP) as a spatial filter and wavelet filt...