Identifying and removing overlaps from adjacent components is important in investigations of C1 modulation by...

During recent years, perceptual/attentional load paradigms have been frequently used to investigate whether the initial visual cortical processing can be modified by spatial attention. For example, Rauss and colleagues reported significant modulations of the earliest component (i.e. the C1) of the visual evoked potential (VEP) as a function of attentional load. It may be questioned, however, whether these load effects represent modulations of the C1 or overlaps from other components. Here we summarize some methods to identify and remove the overlaps, which is important to clarify the question of whether the initial visual cortical processing could be modulated by attention.