Norepinephrine depletion alters single-unit figure rates across cortico-striatal circuits. a, We found neurons in v. striatum, d. striatum, OFC, thalamus, and VTA that increased their firing rates after norepinephrine depletion (Type 1 neurons) and neurons in each of these areas that decreased their firing rates after norepinephrine depletion (Type 2 neurons). b, Treatment with αMT reduced the population firing rate observed in WT mice (n = 163; *p < 0.001). c, Treatment with αMT significantly increased the population firing rate observed in NET-KO mice (n = 275; *p < 0.001). d, WT mice displayed more Type 2 neurons than Type 1 neurons within each brain area investigated. e, NET-KO mice displayed a significantly decreased proportion of Type 2 neurons within v. striatum, orbital frontal cortex, and VTA compared with WT mice (*p < 0.001 for comparisons between genotype; see squares with pink highlights).