The amplitude and phase characteristics of the steady-state visual evoked potential (VEP) and grating perception were studied for an unbiased group of fifteen healthy female subjects. The variability of VEP data, as obtained by using a digital sweep technique, was high between subjects but relatively low within them. Earlier claims that psychophysical detection thresholds can be predicted from ...

It has been found that humans are able to distinguish colours without luminance cues by about 2-4 months of age and that sensitivity to colour difference develops during childhood, reaching a peak around adolescence. This prolonged period of maturation is reflected by improvements in psychophysical threshold measures and by the VEP characteristics of morphology, latency and amplitude. An intra-...

INTRODUCTION Alzheimer's disease (AD) is a long term progressive neurodegenerative disease and might affect the retinal nerve fiber layer thickness (RNFLT) of the eye. There is increasing evidence that visual evoked potentials (VEP), which are an objective way to indicate visual field loss, might be affected by the disease as well. MATERIALS AND METHODS About 22 patients (mean age: 75.9 ± 6.1...

A violation of Local Lorentz Invariance (VLI) and hence the special theory of rel-ativity or a violation of equivalence principle (VEP) in the Kaon system can, in principle , induce oscillations between K 0 and ¯ K 0. We construct a general formulation in which simultaneous pairwise diagonalization of mass, momemtum, weak or gravi-tational eigenstates is not assumed. We discuss this problem in ...

VEPs were recorded with three different spatial frequencies of stimulation in patients affected by idiopathic Parkinsonism and by Parkinsonian syndromes. The detection of VEP abnormalities in Parkinson's disease was dependent on the spatial frequency of the visual stimulus (a vertical square wave grating). The VEP latency was normal in Parkinsonian syndrome patients (except in one patient affec...

Manual reaction time (RT) and visual evoked potentials (VEP) were measured in motion onset and offset detection tasks. A considerable homology was observed between the temporal structure of RTs and VEP intervals, provided that the change in motion was detected as soon as the VEP signal has reached critical threshold amplitude. Both manual reactions and VEP rise in latency as the velocity of the...

The authors examined a series of ten consecutive patients with unilateral, idiopathic central serous choroidopathy. Visual acuities ranged from 20/20 to 20/70 during the active stage. VEPs were recorded to square sizes of 14, 28, and 56 min of arc. Overall, 90% of the patients had statistically significant VEP delays from the affected eye, while only 30% had statistically significant reductions...

The new Mannich base VEP (N,N’-bis-(5,5’-diethyl-barbituryl-1-methyl)-piperazine), has been synthetized by condensation of veronal with formaldehyde and piperazine following a Mannich procedure. The new binuclear complex Cu2VEP(X)4·4H2O , X=ClO4where VEP stands for N,N’-bis-(5,5’-diethyl-barbituryl-1-methyl)-piperazine, were obtained by metal ligand direct synthesis. Tetrahedral geometry of the...

The clinical and visual evoked potential (VEP) findings were analysed in 18 patients with anterior ischaemic optic neuropathy. The VEP studies showed a variety of abnormalities which could be interpreted as being the result of subcomponent interaction consequent upon loss or attenuation of the normal macular-derived P100 component. Delay of normal VEP subcomponents was not seen. The VEP finding...