PURPOSE We assessed retinal ganglion cell (RGC) function, and established a correlation between the neural conduction along the visual pathways and the retinal involvement in Leber's hereditary optic neuropathy (LHON). METHODS A total of 39 individuals carrying a LHON mutation (mean age, 33.35 ± 8.4 years), LHON-unaffected (LU, 22 eyes) or LHON-affected (LA, 17 eyes), underwent visual acuity ...

purpose : to evaluate the efficacy of pattern visual evoked potentials (pvep), standard automated perimetry (sap), short-wavelength automated perimetry (swap), contrast sensitivity (cs), stereoacuity testing in detecting subclinical visual impairment in visually asymptomatic patients with multiple sclerosis (ms) and no history of optic neuritis methods : twenty-seven eyes of 27 patients (7 male...

In order to determine the optimum stimulus conditions for the detection of optic nerve damage due to glaucoma and ocular hypertension, checkerboard pattern reversal visual evoked potentials (VEPs) were recorded from 20 glaucoma patients, 20 ocular hypertensive patients, and 20 age-matched normals. Two check sizes (12' and 48'), two field sizes (14 degrees and 28 degrees), and two alternation ra...

It is a well established fact that Down Syndrome (DS) individuals have a tendency to develop Alzheimer's disease (AD) (Lott, I.T., Head, E., 2005. Alzheimer disease and Down syndrome: factors in pathogenesis. Neurobiol. Aging 26, 383-389). They have therefore been proposed as a model to study the pre-dementia stage of Alzheimer's (Mann, D.M., 1988. The pathological association between Down synd...

Visual evoked potentials (VEPs) in response to flash stimuli were recorded from occipital and central-scalp electrodes in the chimpanzee and gorilla. The most notable occipital component of the VEP was a surface-positive wave (P90), the latency of which decreased with development. Central scalp responses, apparent only in older animals, included a characteristic long-latency 'vertex wave' (N125...

27 of visual evoked potentials (i.e., VEPs) have been used as signal 28 features for BCIs. The design and operation of BCIs that use 29 endogenous ERP components differ both in principle and 30 practice from those of BCIs that use exogenous ERP compo­ 31 nents. This chapter focuses on BCIs that use P300, an endoge­ 32 nous ERP component. Chapter 14 discusses BCIs that use 33 exogenous VEP compo...

  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...

OBJECTIVES Visual evoked potentials (VEPs) show abnormal responses in newly-diagnosed insulin-dependent diabetic (IDDM) patients. Electrophysiological methods allow one to dissect and explore different structures contributing to neural conduction in the visual pathways. The aim of our work was to assess whether the VEP abnormalities are due to impaired function of the retinal layers and/or a de...

PURPOSE The main aim of the study was to evaluate which factors affect the long-time visual function in preterm children, whether it is prematurity or retinopathy of prematurity or perhaps disturbances in the visual pathway. MATERIALS AND METHODS Fifty-eight children with mean birth weight 1016 g (range 520-1500 g) were evaluated at mean age 48 months (range 42-54 months). All children underw...

The purpose of this study was to investigate the effects of refractive error on canine visual evoked potentials with pattern stimulation (P-VEP). Six normal beagle dogs were used. The refractive power of the recorded eyes was measured by skiascopy. The refractive power was corrected to -4 diopters (D) to +2 D using contact lens. P-VEP was recorded at each refractive power. The stimulus pattern ...