The quantity and quality of sleep can impact behaviour, memory, cognition, executive function, attention, mood, and overall quality of life. Sleep disorders in children and adolescents range from behavioural insomnias, sleep breathing disorders, and sleep-wake transition disorders, through to disorders of excessive somnolence. Excessive daytime vi Publications included in this thesis Ludwig, B., Smith, S.S., & Heussler, H. (2018). Associations between neuropsychological, neurobehavioral and emotional functioning and either narcolepsy or idiopathic hypersomnia in children and adolescents.