The neurophysiological effects of exposure to power-frequency magnetic fields at two occupationally-relevant intensities were evaluated in a single-blind study with 18 male and 18 female volunteers. Auditory brainstem (BAEP) and somatosensory (SEP) evoked potentials were recorded before, during and after field exposure (duration = 45 min, frequency = 60 Hz, field intensities = 14.1 or 28.3 micr...

PURPOSE To investigate whether a rapid and practical determination of the temporal frequency characteristic (TFC) of the visual system can be obtained by using the visually evoked potentials (VEPs) elicited by pseudorandom binary sequence (PRBS) stimulation. METHODS VEPs were recorded from eight volunteers. For the conventional steady state VEPs (S-VEP), the eye was stimulated with five stimu...

PURPOSE To evaluate the value of electroretinogram (ERG) and visual evoked potentials (VEP) in children with nonsyndromic microcephaly. METHODS In this observational case series, six children with nonsyndromic microcephaly aged 8.5 to 158 months were examined. Main outcome measures included the amplitude of the flash ERG (photopic, flickering, scotopic, and dark-adapted responses), the amplit...

Genetically manipulated mice are important tools for studies on plasticity and degeneration/regeneration in the visual system. However, a description of the basic properties of the visual performance of the wild type mouse is still lacking. To characterize the visual physiology of the wild type (C57BL/6J) mouse we recorded Visual Evoked Potentials (VEPs) from the primary visual cortex. As compa...

The aim of our study was to investigate the relationship between the metabolic control parameters of diabetes mellitus (glycemia and HbA1c) and visual evoked potentials (VEP) latency values. The study included 61 patients with diabetes mellitus type 1 that were hospitalized at the Clinic for Endocrinology, Diabetes and Metabolic Diseases due to the poor metabolic control. All patients were divi...

Two common artifacts that corrupt evoked responses are noise and background electroencephalogram (EEG). In this paper, a two-level principal component analysis (PCA) is used to reduce these artifacts from single trial evoked responses. The first level PCA is applied to reduce noise from these VEP signals while the second level PCA reduces EEG. The method is used to analyse the object recognitio...

PURPOSE To investigate a proposed postretinal defect in patients with the incomplete form of congenital stationary night blindness (CSNB2) and to compare visual evoked potential (VEP) results with those found in various forms of albinism. METHODS Visual evoked potentials were performed in 10 patients with a diagnosis of CSNB2, 10 subjects with albinism, and 17 normal subjects. Visual evoked p...

PURPOSE Blind individuals who have photoreceptor loss are known to perceive phosphenes with electrical stimulation of their remaining retinal ganglion cells. We proposed that implantable lateral geniculate body (LGB) stimulus electrode arrays could be used to generate phosphene vision. We attempted to refine the basic reference of the electrical evoked potentials (EEPs) elicited by microelectri...

Amblyopia is a neurodevelopmental disorder of vision that occurs when the visual cortex receives decorrelated inputs from the two eyes during an early critical period of development. Amblyopic eyes are subject to suppression from the fellow eye, generate weaker visual evoked potentials (VEPs) than fellow eyes and have multiple visual deficits including impairments in visual acuity and contrast ...