This study investigates the impact of different levels of anesthesia exposure on children's neurocognitive development and evaluates the concurrent validity of different methods that assess neurodevelopmental outcome.

The US Food and Drug Administration (FDA) recently released an official warning regarding the potentially harmful impact of repeated and prolonged (more than three hours) general anesthesia on the child's brain. The potential impact of anesthesia highlights the importance of remediating the need for repeated and prolonged surgery with accompanying anesthesia exposure in a time of cerebral vulnerability and if possible, delay exposure to avoid potentially preventable harm. Therefore, it is crucial to better understand the impact of (different durations and frequencies of) anesthesia exposure on neurodevelopment.

Inclusion Criteria:

• Age 12 months (± four weeks) with a history of general anesthesia exposure (patient group) or without a history of general anesthesia (healthy controls)

Exclusion Criteria:

• Children with comorbid conditions affecting structure and/or function of the central nervous system (e.g. premature birth) will be excluded from participation in this study.

At the outpatient clinic of the department of pediatric surgery, children (< 12 months old) who are scheduled for or already underwent a single short, long or repetitive general anesthesia will be identified by the (fellow) pediatric surgeon. Parents/caretakers will be asked to participate in this study by the (fellow) surgeon who will ask informed consent. Healthy controls exist of eligible acquaintances and children that will be recruited via child health care centres by a member of the research team