Background noise is often discussed in terms of mental costs. In this study the effect of background noise on brain activity as reflected by the direct coupled (DC) potential was investigated by a within design in ten participants. During two successive blocks of 7 min each, participants performed 156 trials of a visual display terminal (VDT)-based visual-spatial attention task without noise an...

Transformational apparent motion (TAM) arises when a shape that is abruptly flashed on and off next to a static shape of similar color or texture appears as a protrusion that extends and retracts smoothly from the static object. Here we report that the strength of the TAM percept can be predicted from the waveform of visual evoked potentials (VEPs) measured while observers rated their percepts....

The visual evoked potential is commonly used to estimate visual acuity in infants. The stimulus used is temporally modulated in order to drive the cortical response. Here it is proposed that distortion products generated by a front-end nonlinearity may contaminate the acuity estimate. Specifically, the nonlinearity might convert temporal modulation of a high spatial frequency grating into appar...

Introduction Studies comparing visual evoked potentials (VEPs) and BOLD signals have found a positive correlation between the VEP amplitude and the magnitude and extent of the BOLD signal [1, 2], but some VEP components are better related to the BOLD signal than others. The strongest spatial correlation have been found between the source location of the N1 peak* and the location of the BOLD sig...

We compared visual evoked potentials and psychophysical reaction times to the onset of first- and second-order motion. The stimuli consisted of luminance-modulated (first-order) and contrast-modulated (second-order) 1 cpd vertical sine-wave gratings drifting rightward for 140 ms at a velocity of 6 degrees /s. For each condition, we analysed the latencies and peak-to-baseline amplitudes of the P...

Visual motion processing is strongly susceptible to adaptation. A variety of patterns have been used as stimuli in previous studies. Three of these, namely random dots, barcode-like gratings, and sinusoidal gratings, were compared in the present study using motion-onset visual evoked potentials (VEPs). We assessed the effects of the adaptation pattern and the test pattern to which the VEP is re...

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 ...

The natural visual acuities of 15 adult persons were predicted on the basis of changes in visual evoked potentials (VEP's) to flashed patterns of various sized dots. An objective method was used to quantify the VEP's, based on the minimum-sized stimulus that would elicit a pattern VEP- the VEP pattern threshold. This measure was highly correlated with recognition and resolution measures of perc...

Objective: Steady-state visual evoked potentials (VEPs) were recorded to study the mechanisms that underlie visual attention. Methods: VEPs were recorded from 1 cycle/degree sinusoidal grating contrast reversed at various temporal frequencies (6–10 Hz). This was displayed in one hemifield. A letter search display was flashed at a random rate in the other hemifield. The subject performed a deman...

Type 1 diabetic mothers' infants show a delay of visual evoked potential (VEP) significantly related to some parameters of poor metabolic control during pregnancy. In the present paper we analyzed the characteristics of VEPs and somatosensory evoked potentials (SEPs) recorded in 16 three-year-old type 1 diabetic mothers' children (DMC). Compared with controls (23 nondiabetic mothers' healthy ma...