Introduction: The main drawback of a Brain-computer Interface based on Steady-State Visual Evoked Potential (SSVEP-BCI) that detects the emergence of visual evoked potentials (VEP) in reaction to flickering stimuli is its muscular dependence due to users must redirect their gaze to put the target stimulus in their field of view. In this work, a novel setup is evaluated in which two stimuli are ...

The visual evoked potential (VEP) to pattern reversal was recorded in 79 patients with neurosyphilis. Sixteen patients (20%) had abnormal VEP latencies with a predominance of pathological VEP values in the group of tabes dorsalis (50%) as compared to general paresis (18%) or meningovascular forms (13%). A comparison of the frequency of abnormal VEPs with that of other ophthalmological tests (vi...

The possibility of a link between medial axes (hereafter called symmetries) and figure salience has recently been proposed [Vision Res. 38 (1998) 2323; Vision Res. 38 (1998) 2429]. In this paper we investigated the characteristics of transient visual evoked potentials (VEPs) associated with stimulus figures designed to have different symmetries. Significant trends were observed for VEP componen...

BACKGROUND The purpose of this study is to validate the use of visual evoked potential (VEP) to objectively quantify visual acuity in normal and amblyopic patients, and determine if it is possible to predict visual acuity in disability assessment to register visual pathway lesions. METHODS A retrospective chart review was conducted of patients diagnosed with normal vision, unilateral amblyopi...

Visual evoked potentials (VEPs) were recorded under binocular and monocular viewing conditions in 19 2- to 10-month-old infants, 19 stereodeficient adults, and 12 normal adults. VEPs were elicited by medium contrast, phase-alternated checkerboards with check sizes ranging from 10-52 min of arc. Binocular VEP summation was defined as the percentage by which the binocular VEP amplitude exceeded t...

OBJECTIVE To further evaluate the potential of slew-rate limiting amplifiers to record electrophysiological signals in spite of concurrent transcranial magnetic stimulation (TMS), and to explore the effects of single-pulse TMS on electroencephalographic (EEG) correlates of functional brain activity. METHODS Visual-evoked potentials (VEPs) to checkerboards were recorded in 7 right-handed subje...

background: parkinson's disease (pd) is a neurodegenerative disorder impairing motor, verbal and other abilities. visual evoked potential (vep) assessment is a useful method for analysis of visual system and its function. the present study was designed in order to evaluate whether vep changes are associated with pd. m aterials and methods: in the present study, 100 subjects encompassing 40 pati...

purpose : to demonstrate visual evoked potential (vep) changes in multiple sclerosis (ms) disease methods : a case series study of vep changes in forty-nine patients with definite, probable and possible diagnoses of ms referred to electrophysiology ward from january 2002 to december 2005. pattern vep was done for those with good visual acuity (va), and flash vep was done for those who did not h...

OBJECTIVE Visual Evoked Potentials (VEPs) following optic neuritis (ON) remain chronically prolonged, although standard visual tests indicate full recovery. We hypothesized that dynamic visual processes, such as motion perception, may be more vulnerable to slowed conduction in the optic nerve, and consequently be better associated with projection rates. METHODS Twenty-one patients with acute ...

purpose : evaluation of efficacy of memantine (n-methyl-d-aspartate receptor antagonist) on visual function of patients with acute non-arteritic ischemic optic neuropathy (naion). methods : the study was conducted as interventional case series from november 2005 through november 2006 in farabi eye hospital . twenty-two patients with acute naion of less than 8 weeks duration entered the study. m...