in patients with nonarteritic anterior ischemic optic neuropathy. Differential diagnosis of concentric visual field defects using electrophysiological methods. patterns of cone degeneration in retinitis pigmentosa with concentric narrowing of the visual field. electroretinograms and visual evoked potentials in retinitis pigmentosa. Documenta of multifocal electroretinograms obtained under monoc...

  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...

PURPOSE This study aimed to compare pattern visual evoked potential (PVEP) components in dyslexic and normal children. METHODS This cross-sectional analytic study recruited 72 children, including 36 dyslexic and 36 normal participants aged 8-12 years. Visual examinations included measurement of distance visual acuity, refraction, and PVEP components of amplitudes and latencies with two differ...

Pattern reversal visual evoked potentials (VEPs) have been elicited in 16 female hyperthyroid patients before and after treatment and compared with those from a similar group of age and sex matched control subjects. No effect on latency was seen, and although larger amplitude values were noted in the thyrotoxic group these too were not significant. We would conclude that hyperthyroidism per se ...

Introduction: Visual evoked potentials contain certain diagnostic information which have proved to be of importance in the visual systems functional integrity. Due to substantial decrease of amplitude in extra macular stimulation in commonly used pattern VEPs, differentiating normal and abnormal signals can prove to be quite an obstacle. Due to developments of use of machine l...

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...

Abstract Background: Opium-dependence having different effects on the nervous system is a common problem, especially in the Middle East and Iran. The aim of this study is evaluating the effects of opium-dependence on visual evoked potential (VEP) in men. Methods: Thirty subjects with both chronic cigarette smoking and opium-dependence (group 1) and 30 subjects with only chronic ciga...

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...