Visually evoked potential

An increased level of exploratory activity immediately after exposure, attributed to reduced anxiety on the part of the rats, was also observed in this study. Decreased avoidance was observed in rats exposed to 125 ppm trichloroethylene 4 hours per day, 5 days per week for 30 days (Goldberg et al. 1964a). Changes in visually evoked potentials (Blain et al. 1992) and electroretinal responses to flash stimulation (Blain et al. 1994) were seen in rabbits exposed to 350 ppm trichloroethylene for 12 weeks (4 days/week, 4 hours/day). The study authors suggested that binding of trichloroethanol to blood proteins may enable it to reach the visual cortex. 

Dissemination in space by MRI evidence of nine or more T2-weighted brain lesions, or two or more cord lesions, or four to eight brain and one cord lesion, or positive visual evoked potentials with four to eight MRI lesions, or positive visual evoked potentials with less than four brain lesions plus one cord lesion. 

NS (children, environmental exposure) Neurological Blood lead correlated with alterations in visual evoked potentials range, 1.4-17.4 Altmann et al. 1998 Winneke et al. 1994... 

Winneke G. 1980. Non-recovery of lead-induced changes of visual evoked potentials in rats. Toxicol Lett 1 77. 

Di Piazza et al. 51 Neomycin (double-blind) 7 days Flapping tremor, bradylalia, patient self-evaluation, visual evoked potential reaction, trial making test E Rif > Neo T Rif = Neo... 

Zeneroli ML, Ventura E, Baraldi M, Penne A, Messori E, Zieve L Visual evoked potentials in encephalopathy induced by galactosamine, ammonia, dimethyldisulfide and octanoic acid. Hepatology 1982 2 532-538. 

Seppalainen AM, Raitta C, Huuskonen MS. 1979. -Hexane-induced changes in visual evoked potentials and electroretinograms of industrial workers. Electroencephal Clin Neurophysiol 47 492-498. 

P. A. Bhaskar, S. Vanchilingam, E. A. Bhaskar, A. Devaprabhu, and R. A. Ganesan. Effect of L-dopa on visual evoked potential in patients with Parkinson s disease. Neurology 36 1119-1121 (1986). 

Reeves RR, Struve FA, Patrick G. (1999). The effects of caffeine withdrawal on cognitive P300 auditory and visual evoked potentials. Clin Electroencephalogr. 30(1) 24-27. 

Lund SP, Simonsen L, Fries AS Two weeks inhalation exposure to 4- tt-butyltoluene causes persistent changes in visually evoked potentials in rats. Pharmacol Toxicol 76(1) 36-40, 1995... 

Figure 3.5 Classification of the components of visually evoked potentials (VEPs). The two negative peaks I and III and the positive peak II were termed the primary response by Ciganek (1961), peaks IV-VII (negative peaks = upwards pointing peaks) being termed the secondary response. The amplitude of these peaks lies in the region of 10-30/iV. In addition to amplitudes (e.g. between peaks I and II), latencies are determined, i.e. the time in milliseconds between the stimulus and the appearance of a peak, e.g. peak IV...

Lanting, P. et al., The cause of increased pupillary light reflex latencies in diabetic patients the relationship between pupillary light reflex and visual evoked potential latencies, EEG Clin. Neurophysiol., 78, 111, 1991. 

Cortical sources of the early components of visual evoked potential. Hum Brain Mapp 15 95-111. 

List of Abbreviations ISI, interstimulus interval LGN, lateral geniculate nucleus M, magnocellular MST, medial superior temporal area MT, medial temporal area NMDA, N-methyl-D-aspartate P, parvocellular ssVEP, steady-state visual evoked potential TE, temporal lobe TEO, temporal occipital area tVEP, transient visual evoked potential YEP, visual evoked potential VI, primary visual cortex... 

Di Russo F, Martinez A, Sereno MI, Pitzalis S, Hillyard SA. 2002. Cortical sources of the early components of the visual evoked potential. Hum Brain Mapp 15 95-111. 

Greenstein VC, Seliger S, Zemon V, Ritch R. 1998. Visual evoked potential assessment of the effects of glaucoma on visual subsystems. Vision Res 38 1901-1911. 

Krishnan GP, Vohs JL, Hetrick WP, et al. 2005. Steady state visual evoked potential abnormalities in schizophrenia. Clin Neurophysiol 116 614-624. 

McKeeffy DJ, Russell MH, Murray IJ, Kulikowski JJ. 1996. Amplitude and phase variations of harmonic components in human achromatic and chromatic visual evoked potentials. Vis Neurosci 13 639-653. 

Zemon V, Ratliff F. 1982. Visual evoked potentials Evidence for lateral interactions. Proc Natl Acad Sci USA 79 5723-5726. 

Antal A, Keri S, Bodis-Wollner I (1997) Dopamine D2 receptor blockade tilters the primary and cognitive components of visual evoked potentials in the monkey, Macaca fascicularis. Neurosci Lett 232 179-181... 

Electrodiagnostic testing may be useful in the diagnosis of demyelinating optic neuropathy. The visual evoked potential shows a delayed peak latency amplitude in MS patients. 

Preacute signs and symptoms do occur. In some patients atrophy of retinal nerve fibers, an altered Farnsworth-Munsell 100-hue test, and altered visual evoked potentials occur before the actual attack. 

The visual evoked potential recordings in LHON become desynchronized early in the disease. This is accompanied by a prolonged latency and reduction in peak amplitude. In the later stages of the disease, visual evoked potentials may diminish entirely. Nerve fiber analysis shows severe and progressive loss of the NFL. 

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