- increased perinatal risk factors, such as preterm birth, hypoxic ischemic encephalopathy (asphyxia), and morphological brain abnormalities. These "at-risk" children are included in the regular clinical follow-up program at St. Olavs University Hospital comprising a standard examination at 3 months of age (for preterm born children: 3 months post term, so-called corrected age). At this examination, infants who exhibit two or more of the following additional risk factors will be eligible for study participation: