The stimulus duration was 700 msec, and each stimulus was replaced on the screen instantaneously with the next one.
Cues were presented for 500 msec and the stimulus was presented for 500 msec.
ERPs recorded from babies of nonsmokers began to distinguish consonant and vowel sounds within 150 msec after stimulus onset and discriminated among a larger number of different speech syllables.
The ERPs were baseline corrected for 100 msec before stimulus presentation and visually inspected.
The "stimulus-locked" components, which are measured in relation to when the stimulus first appeared on the screen, were segmented 100 msec before and 1,000 msec after stimulus onset; the "response-locked" components, which are measured in relation to when the child pressed the button, were segmented 300 msec before and 500 msec after button press.
The interstimulus interval was 1750 msec, and the duration of each stimulus (target and non-target) was 450 msec.
These are further separated into an unconscious attention component (head part of SCIT curve) at stimulus presentation times of 16 64 msec and a conscious attention component (tail part of SCIT curve) with stimulus presentation times of 80 176 msec.
This ERP response started at 50 msec, peaked around 100 msec, and was absent when the same stimuli were not behaviorally relevant.
Visual inspection of the tactile ERPs identified positive peaks at ∼50, 100, and 200 msec after tactile stimulus onset near the contralateral somatosensory cortices (at electrodes C3 and C4, according to the international 10 20 system), corresponding to the canonical P50, P100, and P200.
Rivalry stimuli were briefly presented for a duration varied from 10 msec to 500 msec, and subjects reported which of the two stimuli (the +45° grating or the −45° grating) was dominant (Figure 1B).
