Future work must determine the neurophysiological correlates of this behavioral phenotype, but multiple studies have found evidence of sound-evoked hyperactivity and circuit hyperexcitability in the auditory cortex of FMR1 KO mice (Rotschafer and Razak, 2013; Lovelace et al., 2018; Goswami et al., 2019) and FXS individuals (Van der Molen et al., 2012; Ethridge et al., 2016). Here, FMR1 is linked to fragile X syndrome.