BACE1 and attention deficit-hyperactivity disorder: Neuregulin 1 (nrg1), a substrate of BACE1, is a pre‐synaptic protein thought to be implicated in a number of neurodegenerative diseases and psychiatric/neurodevelopmental disorders such as AD, attention deficit hyperactive disorder (ADHD) and schizophrenia (Shi & Bergson, 2020).