Child and adolescent neuropsychiatry

Child neuropsychiatry encompasses childhood and adolescent psychiatric syndromes of neurobiological origins. It is an evolving discipline without consensus on its exact boundary. Given the inconsistencies, we provide a historical perspective through which different conceptualisations of child neuropsychiatry can be understood and reconciled within the coherent whole. Four specific contrasting conditions are selected in this chapter to illustrate some key principles: attention deficit/hyperactivity disorder (ADHD) as ‘a diffuse brain disorder’; childhood cranial tumours as ‘a localised brain disorder’; fetal alcohol spectrum disorders (FASD) as ‘a disorder of a specific cause’ represented by toxin exposure; and epilepsy as ‘a disorder of complex aetiology’. ADHD and cranial tumour represent the extremes of the polar divide between ‘a childhood neuropsychiatric disorder’ and the ‘the neuropsychiatric manifestation of a childhood neurological disorder’. In contrast, FASD and epilepsy illustrate how specific and complex aetiology can both present with a wide spectrum of psychiatric disorders. Atypical presentations of psychiatric symptoms, idiosyncratic treatment response and ‘diagnostic overshadowing’ are also considered. We emphasize that child neuropsychiatric conditions are not fixed entities, despite they conform to diagnostic criteria stipulated by authoritative taxonomic systems. Rather, they are the results of the dynamic interplay between environmental factors, developmental maturity, mitigating factors, aberrant neural networks and innate disease liability. Our goal is to equip our readers with a more critical approach for further reading and research.