Auditory Slow Wave Enhancement After Concussion

Inclusion Criteria: * Informed Consent as documented by signature * Age between 6 and 18 years * Good knowledge of German of the patient and at least one legal representative * Patients: Presentation to the Emergency of the University Children's Hospital Zurich because of a concussion (diagnosed by medical doctor) Exclusion Criteria: * Preterm birth (\< 37 gestational weeks) * Diagnosed hearing disorder * Psychiatric, syndromal, or neurological pre-existing condition (except for previous concussion) * Skin disorder/skin problem in the face/ear area that requires Treatment * Usage of neuroactive substances * Patients: Concomitant injury that requires intense pain medication or a prolonged hospital stay, or that causes limited use of the dominant Hand * Patients: Previous moderate-severe TBI * Controls: Injury of the dominant hand, on head, arm, or leg * Controls: Previous TBI (of any severity) Additional inclusion criteria for the optional MRI measurement for both groups: * Age at least 8 years * Fulfilment of all MRI safety criteria * The participant and the legal representative would want to know about incidental findings. * Girls: No pregnancy or breast feeding.