scholarly journals A Comprehensive Review on Methodologies Employed for Visual Evoked Potentials

Scientifica ◽  
2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Ruchi Kothari ◽  
Pradeep Bokariya ◽  
Smita Singh ◽  
Ramji Singh

Visual information is fundamental to how we appreciate our environment and interact with others. The visual evoked potential (VEP) is among those evoked potentials that are the bioelectric signals generated in the striate and extrastriate cortex when the retina is stimulated with light which can be recorded from the scalp electrodes. In the current paper, we provide an overview of the various modalities, techniques, and methodologies which have been employed for visual evoked potentials over the years. In the first part of the paper, we cast a cursory glance on the historical aspect of evoked potentials. Then the growing clinical significance and advantages of VEPs in clinical disorders have been briefly described, followed by the discussion on the earlier and currently available methods for VEPs based on the studies in the past and recent times. Next, we mention the standards and protocols laid down by the authorized agencies. We then summarize the recently developed techniques for VEP. In the concluding section, we lay down prospective research directives related to fundamental and applied aspects of VEPs as well as offering perspectives for further research to stimulate inquiry into the role of visual evoked potentials in visual processing impairment related disorders.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
J. M. Miguel ◽  
M. Roldán ◽  
C. Pérez-Rico ◽  
M. Ortiz ◽  
L. Boquete ◽  
...  

AbstractThis study aimed to assess the role of multifocal visual-evoked potentials (mfVEPs) as a guiding factor for clinical conversion of radiologically isolated syndrome (RIS). We longitudinally followed a cohort of 15 patients diagnosed with RIS. All subjects underwent thorough ophthalmological, neurological and imaging examinations. The mfVEP signals were analysed to obtain features in the time domain (SNRmin: amplitude, Latmax: monocular latency) and in the continuous wavelet transform (CWT) domain (bmax: instant in which the CWT function maximum appears, Nmax: number of CWT function maximums). The best features were used as inputs to a RUSBoost boosting-based sampling algorithm to improve the mfVEP diagnostic performance. Five of the 15 patients developed an objective clinical symptom consistent with an inflammatory demyelinating central nervous system syndrome during follow-up (mean time: 13.40 months). The (SNRmin) variable decreased significantly in the group that converted (2.74 ± 0.92 vs. 4.07 ± 0.95, p = 0.01). Similarly, the (bmax) feature increased significantly in RIS patients who converted (169.44 ± 24.81 vs. 139.03 ± 11.95 (ms), p = 0.02). The area under the curve analysis produced SNRmin and bmax values of 0.92 and 0.88, respectively. These results provide a set of new mfVEP features that can be potentially useful for predicting prognosis in RIS patients.


Author(s):  
Gastone G. Celesia ◽  
Neal S. Peachey

Electrophysiological testing of vision permits the objective assessment of the function of the retina, visual pathways, and cortices. This chapter covers visual evoked potentials (VEPs) and electroretinography (ERG). Flash ERG is useful in evaluating the outer retinal function and specifically helping in the diagnosis of retinal degeneration, monitoring the progress of retinal diseases, monitoring the retinal toxicity of drugs, and understanding the pathophysiology of retinal disorders. VEPs to various stimuli are useful in evaluating macular disorders, diagnosing optic neuropathies, detecting silent pathologies in the absence of other clinical signs of visual impairment, and evaluating disturbances of visual processing in degenerative diseases of the central nervous system. Simultaneous recording of pattern ERG and pattern VEP permits the differentiation between maculopathies and optic neuropathy.


2014 ◽  
Vol 72 ◽  
pp. 48-57 ◽  
Author(s):  
Sinem Aras ◽  
Gamze Tanriover ◽  
Mutay Aslan ◽  
Piraye Yargicoglu ◽  
Aysel Agar

2015 ◽  
Vol 68 ◽  
pp. 82-93 ◽  
Author(s):  
Voyko Kavcic ◽  
Regina L. Triplett ◽  
Anasuya Das ◽  
Tim Martin ◽  
Krystel R. Huxlin

1982 ◽  
Vol 54 (3) ◽  
pp. 975-978
Author(s):  
Akihiro Yagi

5 subjects were assigned two tasks during which they were simultaneously presented brightness-changes of the spot light on the CRT and the speech in a foreign language. They were asked to count the number of the changes in the visual task and listen to the speech to discern the content in the auditory task. A pair of averaged visual evoked potentials (VEP) to the brightness-changes were obtained for each task to calculate a subset correlation as an index of the variance of VEP. The mean correlation coefficient of VEP across the subjects was significantly higher during the visual task than that in the auditory task. This means that VEP was more stable during the visual task. The result suggests that the subset correlation measure might be available to evaluate visual information-processing load.


1994 ◽  
Vol 10 (2) ◽  
pp. 117-123 ◽  
Author(s):  
Kathryn North ◽  
Cheryl Cochineas ◽  
Edward Tang ◽  
Elizabeth Fagan

Sign in / Sign up

Export Citation Format

Share Document