Objective Assessment and Detection of Hemianopia and Hemineglect with Visual Evoked Potentials

1991 ◽  
Vol 11 (1) ◽  
pp. 49-58 ◽  
Author(s):  
M. De Keyser ◽  
A Neetens ◽  
I. Vissenberg
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Objective Assessment ◽  
Visual Evoked

Visual Evoked Potentials and Electroretinograms

2017 ◽  
Author(s):  
Gastone G. Celesia ◽  
Neal S. Peachey
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Visual Processing ◽  
Objective Assessment ◽  
Clinical Signs ◽  
Simultaneous Recording ◽  
Pattern Erg ◽  
Pattern Vep ◽  
Toxicity Of Drugs ◽  
Visual Evoked

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.

scholarly journals Rapid and Objective Assessment of Neural Function in Autism Spectrum Disorder Using Transient Visual Evoked Potentials

PLoS ONE ◽  
2016 ◽  
Vol 11 (10) ◽  
pp. e0164422 ◽  
Author(s):  
Paige M. Siper ◽  
Vance Zemon ◽  
James Gordon ◽  
Julia George-Jones ◽  
Stacey Lurie ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Objective Assessment ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Neural Function ◽  
Visual Evoked

DECODING OF STEADY-STATE VISUAL EVOKED POTENTIALS BY FRACTAL ANALYSIS OF THE ELECTROENCEPHALOGRAPHIC (EEG) SIGNAL

Fractals ◽  
2018 ◽  
Vol 26 (06) ◽  
pp. 1850092 ◽  
Author(s):  
HAMIDREZA NAMAZI ◽  
TIRDAD SEIFI ALA ◽  
HOVAGIM BAKARDJIAN
Keyword(s):  
Steady State ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Fractal Structure ◽  
Visual Stimulation ◽  
Fractal Theory ◽  
Objective Assessment ◽  
Eeg Signal ◽  
Brain Response ◽  
Visual Evoked

Analysis of the brain response to different types of external stimuli has always been one of the major research areas in behavioral neuroscience. The electroencephalography (EEG) technique combined with different signal analysis approaches has been especially successful in revealing the detailed dynamic properties of the neural response to exogenous stimulation. In this analysis, we evaluated the nonlinear structure of the EEG signal using fractal theory in rest and visual stimulation (checkerboard reversal at 8, 14 and 28[Formula: see text]Hz). Our analysis showed a significant influence of stimulation on the fractal structure of EEG signal. On comparison between different conditions, 14-Hz steady-state visual evoked potentials (SSVEPs), previously shown to trigger an optimal brain response, exhibited the greatest influence on the complexity of the EEG signal. On the other hand, we observed the lowest complexity of EEG signal in the post-stimulation rest period. Statistical analysis confirmed significant differences in the fractal structure of the EEG signal between rest and different stimulation conditions. These findings demonstrate for the first time a direct relationship between the efficiency of brain processing and the complexity of the measured EEG signal, which could be employed for objective assessment and classification in various experimental paradigms.

Study on Image Quality Assessment with Scale Space Approach Using Index of Visual Evoked Potentials

2011 ◽  
pp. 165-176
Author(s):  
Hidehiko Hayashi ◽  
Akinori Minazuki
Keyword(s):  
Image Quality ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Image Quality Assessment ◽  
Objective Assessment ◽  
Scale Space ◽  
Assessment Method ◽  
Pattern Reversal ◽  
Scalar Parameter ◽  
Visual Evoked

This chapter presents an objective assessment method of image quality using visual evoked potentials (VEPs) to image engineer field based on multi-disciplinarily approach such as knowledge of neurobiology, image recognition theory, or computer vision. The multi-disciplinarily based objective assessment method applies Gaussian scale-space filtering in order to define a scalar parameter to depict blur image. In the experiment, visual stimuli are provided by the scalar parameter, and subjects are detected using VEPs. Their VEPs are recoded during observation of the checkerboard pattern reversal (PR) stimuli, and are analyzed with a latency of about Negative 145 msec (N145) component. The result of the experiment was that latency of N145 components were long about10-20 msec when parameters were large vale (more blur). This result shows one example of availableness for the multi-disciplinarily based objective assessment of image quality by integrating the pattern reversal visual evoked potential (PR-VEP) and the scale-space theory.

scholarly journals Flash visual evoked potentials in diurnal birds of prey

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2217 ◽  
Author(s):  
Maurizio Dondi ◽  
Fabio Biaggi ◽  
Francesco Di Ianni ◽  
Pier Luigi Dodi ◽  
Fausto Quintavalla
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Clinical Setting ◽  
Objective Assessment ◽  
Birds Of Prey ◽  
Flash Visual Evoked Potentials ◽  
Saker Falcon ◽  
Wave Morphology ◽  
Parabuteo Unicinctus ◽  
Visual Evoked

The objective of this pilot study was to evaluate the feasibility of Flash Visual Evoked Potentials (FVEPs) testing in birds of prey in a clinical setting and to describe the protocol and the baseline data for normal vision in this species. FVEP recordings were obtained from 6 normal adult birds of prey: n. 2 Harris’s Hawks (Parabuteo unicinctus), n. 1 Lanner Falcon (Falco biarmicus), n. 2 Gyrfalcons (Falco rusticolus) and n. 1 Saker Falcon (Falco cherrug). Before carrying out VEP tests, all animals underwent neurologic and ophthalmic routine examination. Waveforms were analysed to identify reproducible peaks from random variation of baseline. At least three positive and negative peaks were highlighted in all tracks with elevated repeatability. Measurements consisted of the absolute and relative latencies of these peaks (P1, N1, P2, N2, P3, and N3) and their peak-to-peak amplitudes. Both the peak latency and wave morphology achieved from normal animals were similar to those obtained previously in other animal species. This test can be easily and safely performed in a clinical setting in birds of prey and could be useful for an objective assessment of visual function.

scholarly journals Flash visual evoked potentials in diurnal birds of prey

2016 ◽  
Author(s):  
Maurizio Dondi ◽  
Fabio Biaggi ◽  
Francesco Di Ianni ◽  
Pier Luigi Dodi ◽  
Fausto Quintavalla
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Clinical Setting ◽  
Objective Assessment ◽  
Birds Of Prey ◽  
Flash Visual Evoked Potentials ◽  
Saker Falcon ◽  
Wave Morphology ◽  
Parabuteo Unicinctus ◽  
Visual Evoked

The objective of this pilot study was to evaluate the feasibility of Flash Visual Evoked Potentials (FVEPs) testing in birds of prey in a clinical setting and to describe the protocol and the baseline data for normal vision in this species. FVEP recordings were obtained from 6 normal adult birds of prey: n. 2 Harris's Hawks (Parabuteo unicinctus), n. 1 Lanner Falcon (Falco biarmicus), n. 2 Gyrfalcons (Falco rusticolus) and n. 1 Saker Falcon (Falco cherrug). Before carrying out VEP tests, all animals underwent neurologic and ophthalmic routine examination. Waveforms were analysed to identify reproducible peaks from random variation of baseline. At least three positive and negative peaks were highlighted in all tracks with elevated repeatability. Measurements consisted of the absolute and relative latencies of these peaks (P1, N1, P2, N2, P3, and N3) and their peak-to-peak amplitudes. Both the peak latency and wave morphology achieved from normal animals were similar to those obtained previously in other animal species. This test can be easily and safely performed in a clinical setting in birds of prey and could be useful for an objective assessment of visual function.

Study on Image Quality Assessment with Scale Space Approach Using Index of Visual Evoked Potentials

2013 ◽  
pp. 927-938
Author(s):  
Hidehiko Hayashi ◽  
Akinori Minazuki
Keyword(s):  
Image Quality ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Image Quality Assessment ◽  
Objective Assessment ◽  
Scale Space ◽  
Assessment Method ◽  
Pattern Reversal ◽  
Scalar Parameter ◽  
Visual Evoked

This chapter presents an objective assessment method of image quality using visual evoked potentials (VEPs) to image engineer field based on multi-disciplinarily approach such as knowledge of neurobiology, image recognition theory, or computer vision. The multi-disciplinarily based objective assessment method applies Gaussian scale-space filtering in order to define a scalar parameter to depict blur image. In the experiment, visual stimuli are provided by the scalar parameter, and subjects are detected using VEPs. Their VEPs are recoded during observation of the checkerboard pattern reversal (PR) stimuli, and are analyzed with a latency of about Negative 145 msec (N145) component. The result of the experiment was that latency of N145 components were long about10-20 msec when parameters were large vale (more blur). This result shows one example of availableness for the multi-disciplinarily based objective assessment of image quality by integrating the pattern reversal visual evoked potential (PR-VEP) and the scale-space theory.

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