The Screening Visit will occur at the UCI Child Development Center and will allow for the determination of appropriateness of each subject's inclusion into the study. The Principal Investigator or his/her designee must obtain written signed and dated consent for the subject to participate in the study from the subject's parent(s)/legally authorized representative and assent must be given by the subject, prior to any study related procedures being performed. This visit is expected to last 3-4 hours and may take place across more than one day.