Imaging studies have identified alterations in both morphology [44-46] and activation patterns [47,48] in the striatum of FXS patients, but the function of dopaminergic projections from the midbrain substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) to their forebrain targets in the dorsal striatum and nucleus accumbens (NAc) have been less extensively investigated than cortical circuits in Fmr1-null mice. The gene discussed is FMR1; the disease is fragile X syndrome.