The human brain rapidly detects faces in the visual environment. We recently presented a sweep visual evoked potential approach to objectively define face detection thresholds as well as suprathreshold response functions (Ales, Farzin, Rossion, & Norcia, 2012). Here we determined these parameters are affected by orientation (upright vs. inverted) and contrast polarity (positive vs. negative), t...

Cortical visual evoked potentials (VEPs) in response to gratings temporally modulated in counterphase were recorded in normal and dark-reared pigmented rats. Temporal modulation was either sinusoidal (0.25-15 Hz, steady state condition) or abrupt (0.5 Hz, transient condition). In normals, the amplitude spectrum of contrast VEPs has two peaks (at about 0.5 and 4 Hz) and a high temporal frequency...

Sparse representation is a powerful tool in signal denoising, and visual evoked potentials (VEPs) have been proven to have strong sparsity over an appropriate dictionary. Inspired by this idea, we present in this paper a novel sparse representation-based approach to solving the VEP extraction problem. The extraction process is performed in three stages. First, instead of using the mixed signals...

We consider the problem of detecting visual evoked potentials (VEP's). A matched subspace lter is applied to the detection of the VEP and is demonstrated to perform better than a number of other evoked potential (EP) detectors. Unlike single-harmonic detectors, the MSF detector is suitable for detecting multi-harmonic VEP's. Moreover, the MSF is optimal in the uniformly most powerful (UMP) sens...

22 Evoked potentials (EPs) are observed in motor cortical local field potentials (LFPs) during 23 movement execution (Movement Related Potentials, MRPs) and in response to relevant 24 visual cues (Visual Evoked Potentials, VEPs). Motor cortical EPs may be directionally 25 selective, but little is known concerning their relation to other aspects of motor behavior, such 26 as task timing and perf...

This study investigated the effect of anodal tDCS on motor control and corticomotor excitability in healthy controls, with the long-term goal of investigating the use of anodal tDCS to improve motor function in covertly aware vegetative state patients. Experiment I investigated the effects of anodal tDCS on a motor reaction time task, and found no effect of tDCS on performance, whether or not p...