Dopaminergic modulation of synaptic transmission also appears disrupted in the prefrontal cortex in fmr1-KO mice.54 Indeed, evidence has been mounting for dysregulated dopamine signaling in FXS.55, 56 Most recently, the accumbens has been found to be an area of disrupted long-term potentiation and disrupted synaptic functioning in a mouse model of FXS57 and in the same study that observed hyperactivity and a lack of social discrimination, an increase in striatal dopamine was also observed in fmr1-KO mice.30 This evidence concerns the gene FMR1 and fragile X syndrome.