In this paper, we purpose a diagnostic procedure to identify the optic nerve disease from visual evoked potential (VEP) signals using an Artificial Neural Network (ANN). Multilayer feed forward ANN trained with a Levenberg Marquart backpropagation algorithm was implemented. The correct classification rate was 96.87% for subjects having optic nerve disease and 96.66% for healthy subjects. The en...

OBJECTIVE To determine if sweep visual evoked potential (VEP) acuity is predictive of recognition acuity in children with albinism. METHODS A retrospective review was performed in children with albinism who underwent sweep VEP testing from 1992 to 2003. All patients had a complete ophthalmologic examination with either binocular or monocular sweep VEP testing and at least 5 years of follow-up...

Between attacks, migraine patients are characterized by potentiation instead of habituation of stimulation-evoked cortical responses. It is debated whether this is due to increased or decreased cortical excitability. We have studied the changes in visual cortex excitability by recording pattern-reversal visual evoked potentials (PR-VEP) after low- and high-frequency repetitive transcranial magn...

We report a case of traumatic optic neuropathy accompanying a grease gun injury to the orbit. A 48-year-old man with a grease gun injury visited our clinic with decreased visual acuity, proptosis and limited extraocular movement (EOM). Orbital CT revealed a crescent mass of fat in the medial intraconal space. The grease was exuded from a lacerated conjunctival wound. The visual evoked potential...

In the present overview, practical application of the visual evoked potential (VEP) in paediatric neuro-ophthalmology is described across a wide range of ophthalmogenetic disorders, including albinism, Pelizaeus-Merzbacher disease and spastic paraplegia. The VEP approach is based on a four parameter subdivision of the electrophysiological response which includes, (1) amplitude (microV), (2) lat...

The last 15 years have seen a rapid expansion in studies on human visual evoked potentials (VEP), both a t the fundamental and at the clinical level. A wide variety of stimulus conditions have been explored,’ new types of mathematical tools have been i n t r o d ~ c e d , ~ . ~ and there has been an increasing appreciation of possible VEP correlates with underlying physiological mechanisms! Var...

A procedure for recording the electroretinogram (ERG) and the visual evoked potential (VEP) in freely moving cats was developed and used to test the visual toxicity of nalidixic acid. The electrodes for recording the ERG and VEP were implanted chronically in the sclera of the eye and on the surface of the visual cortex, respectively. Both the ERG and VEP were simultaneously recorded in freely m...

The visual evoked potential (VEP) generated by the amblyopic visual system demonstrates reduced amplitude, prolonged latency, and increased variation in response timing (phase-misalignment). This study examined VEPs before and after occlusion therapy (OT) and whether phase-misalignment can account for the amblyopic VEP deficits. VEPs were recorded to 0.5-4cycles/degree gratings in 10 amblyopic ...

The present study compares behaviour-dependent and physostigmine-induced changes of the visual evoked potential (VEP) in unrestrained rats to provide further indications on the role of acetylcholine in the behavioural VEP modulation. On 30 rats the VEPs on the pial surface of the primary visual cortex were investigated during five spontaneous behavioural states. Physostigmine, carbachol and nic...