Incidentally, while cortical hyperexcitability may indeed relate to intellectual disability in AS, similar levels of intellectual impairment occur without high-amplitude delta activity in duplication 15q11.2-q13.1 syndrome, in which the UBE3A locus is duplicated rather than deleted (Frohlich et al. 2016, 2019b). Here, UBE3A is linked to Cognitive impairment.