نتایج جستجو برای: visual evoked potentials wavelet transform

تعداد نتایج: 612163  

Journal: :Brain and language 1999
E Başar T Demiralp M Schürmann C Başar-Eroglu A Ademoglu

On the basis of a systems theoretical approach it was hypothesized that event-related potentials (ERPs) are superpositions of stimulus-evoked and time-locked EEG rhythms reflecting resonance properties of the brain (Başar, 1980). This approach led to frequency analysis of ERPs as a way of analyzing evoked rhythms. The present article outlines the basic features of ERP frequency analysis in comp...

Journal: :بینا 0
علیرضا جعفری a jafari international branch, shahid beheshti university of medical sciences, tehran, iranدانشگاه علوم پزشکی تهران- مرکز تحقیقات توانبخشی- بخش الکتروفیزیولوژی علی میرزاجانی a mirzajani rehabilitation research center tehran university of medical sciences, tehran, iranدانشگاه علوم پزشکی تهران- مرکز تحقیقات توانبخشی- بخش الکتروفیزیولوژی محمد آقازاده امیری m amiri school of rehabilitation shahid beheshti university of medical sciences, tehran, iranدانشگاه علوم پزشکی تهران- مرکز تحقیقات توانبخشی- بخش الکتروفیزیولوژی

purpose: to evaluate the effect of vertical prism induced stress on binocular visual evoked potentials. methods: using checkerboard stimulus patterns in two spatial frequencies (sfs) of 0.48 cpd as a low sf and 2.18 cpd as a moderate sf reversing with temporal frequency of 4 hz, the effect of increasing visual stress using vertical prisms of 0, 1, 2 and 3 prism diopters on binocular visual evok...

Journal: :journal of current ophthalmology 0
جواد هرویان javad heravian علی اکبر صابرمقدم ali akbar saber moghaddam مرضیه نجاران marzieh najjaran عباس عظیمی abbas azimi هادی استادی مقدم hadi ostadimoghaddam عباسعلی یکتا abbasali yekta محسن فروغی پور

purpose : to evaluate the efficacy of pattern visual evoked potentials (pvep), standard automated perimetry (sap), short-wavelength automated perimetry (swap), contrast sensitivity (cs), stereoacuity testing in detecting subclinical visual impairment in visually asymptomatic patients with multiple sclerosis (ms) and no history of optic neuritis methods : twenty-seven eyes of 27 patients (7 male...

2002
Daniel Senkowski Christoph S. Herrmann

Objective: The present study examined oscillatory brain activity of the EEG gamma band and event-related potentials (ERPs) with relation to the difficulty of a visual discrimination task. Methods: Three tasks with identical stimulus material were performed by 9 healthy subjects. The tasks comprised a passive control task, and an easy and a hard visual discrimination task, requiring discriminati...

Journal: :Journal of Neurology, Neurosurgery & Psychiatry 1983

2000
R.Quian Quiroga

We present a method for the analysis of electroencephalograms (EEG). In particular, small signals due to stimulation, so-called evoked potentials (EPs), have to be detected in the background EEG. This is achieved by using a denoising implementation based on the wavelet decomposition. One recording of visual evoked potentials, and recordings of auditory evoked potentials from four subjects corre...

Ali  Mirzajani Ebrahim Jafarzadehpur, Enayatollah  Osroosh Mohammad Reza Talebnejad, Saeedeh Hosseinmenni

Background: We compared the wave amplitude of visually evoked potential (VEP) between patients with esotropic and anisometropic amblyopic eyes and a normal group.Methods: The wave amplitude of VEP was documented in 2 groups of persons with amblyopia (15 with esotropia and 28 with anisometropia) and 1 group of individuals with normal visual acuity (n, 15). The amplitude of P100 was recorded mono...

Journal: :Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology 2004
Niko A Busch Stefan Debener Cornelia Kranczioch Andreas K Engel Christoph S Herrmann

OBJECTIVE The effects of stimulus size, duration and eccentricity on the visual gamma-band response (GBR) in human EEG were investigated and compared to visual evoked potentials (VEPs) in order to differentiate in future (and past) experiments whether changes in GBRs are due to stimulus-related (exogenous) or cognitive effects. METHODS EEG was recorded from 23 subjects while they performed a ...

1996
S. Wei

In this paper we introduce a recognition and reconstruction method for late auditory evoked potentials (AEPs) using wavelet analysis. AEPs are part of the Electroencephalo-gram (EEG) in reaction to acoustic stimuli and are used for diagnostic purposes. The decomposition of the EEG measurement data into subbands can yield a parameteriza-tion of the AEP using a small number of signiicant coee-cie...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید