Considering the high prevalence of sleep problems (and in particular of insomnia) in the individuals with ASD as well as the known role of hypocretin in the wake-sleep circadian rhythm, Messina et al. hypothesized that patients with ASD may have a hypocretinergic system dysfunction consisting of an increased activity (24), probably caused by an amygdala dysfunction, the latter suggested by functional magnetic resonance imaging studies in adults and children with ASD (25–27). Here, HCRT is linked to insomnia.