The primary goal of this study is to systematically describe early neurodevelopment using a complementary set of observational and neurophysiological measures that may predict cognitive and motor delays earlier than currently possible for infants with Complex Congenital Heart Disease (CCHD).

The investigators' long-term goals are to develop a method of identifying infants likely to have adverse neurodevelopmental outcomes following neonatal treatment for CCHD and to develop and test interventions that can be applied early in infancy. The necessary first step is to systematically describe early neurodevelopment using a complementary set of observational and neurophysiological measures that may predict cognitive and motor delays earlier than currently possible for infants with CCHD. Each measure provides unique information about development and will include (1) neuroimaging for brain maturity and brain injury, (2) hair and fingernails for cortisol and saliva for immune system function, (3) heart rate variability (HRV) for autonomic nervous system function (ANS), (4) Bayley Scales of Infant Development (BSID-III) for cognitive and motor function, (5) a naturalistic play session incorporating kicking, general movement analysis, or the Test of Infant Motor Performance (TIMP) for motor development, and (6) the mobile paradigm for learning, memory, and task-specific coordination. The investigators will look at types of relationships among these measures within each time point for description of development and across each time point for prediction of development. The investigators' core hypotheses are that infants with CCHD will have measurable deficits in cognitive and motor development birth to ~ 6 months of age when compared with a healthy control group and that a typology developed from neurodevelopmental measures will reliably predict cognitive and motor delay in the first six months of life in infants with CCHD.

Inclusion Criteria:

• at least 36 weeks gestational age
• diagnosed with a Complex Congenital Heart Defect
• have at least one English-speaking adult family member

Exclusion Criteria:

• presence of co-existing, non-cardiac congenital anomalies
• ongoing post-operative cardiac pacing

Participants are infants born with a complex congenital heart defect.Cardiac defects include, but are not be limited to: atrioventricular canal defect, double outlet right ventricle, hypoplastic left heart syndrome, interrupted aortic arch, pulmonary atresia, tetralogy of Fallot, and transposition of the great arteries.All participants are recruited from Nationwide Children's Hospital in Columbus, OH. Healthy infants will also be enrolled as a comparison group.