These findings provide the first evidence, to our knowledge, that HDAC5 in DS contributes to impulsive and inflexible decision-making, behavioral deficits previously observed after chronic drug use (Stalnaker et al., 2006, 2009; Roesch et al., 2007; Takahashi et al., 2007; Burton et al., 2015, 2017, 2018; Brockett et al., 2018; Vázquez et al., 2019; Pribut et al., 2021). The gene discussed is HDAC5; the disease is Dravet syndrome.