Fig. 5: CeA ChR2 shock-rod attraction recruits mesocorticolimbic incentive circuitry.

Brain map shows elevated Fos expression in recruited mesocorticolimbic structures in CeA ChR2 rats (N = 9, blue outline; colors denote % Fos ChR2 elevation immediately after a final exposure to shock rod compared to eYFP control rats (N = 6) and to homecage control baseline rats (N = 4). Cortical regions included medial orbitofrontal cortex (mOFC; one-way ANOVA between baseline homecage, eYFP, and ChR2 Fos: F_2,33 = 4.28, p = 0.02, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.025), far-posterior insula (one-way ANOVA: F_2,33 = 4.28, p = 0.02, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.03), and infralimbic cortex (one-way ANOVA: F_2,33 = 4.38, p = 0.02, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.012). Subcortical structures included nucleus accumbens subregions: rostromedial quadrant of medial shell shown (F_2,33 = 4.96, p = 0.01, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.018), caudal half of medial shell (F_2,33 = 0.58, p = 0.57), core (NAc core (all subregions combined); F_2,33 = 0.2, p = 0.82), ventral pallidum (F_2,33 = 0.57, p = 0.57), perifornical area in lateral hypothalamus (F_2,33 = 3.13, p = 0.049, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.014), basolateral amygdala (F_2,33 = 2.63, p = 0.04, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.012), caudal ventral tegmental area (F_2,33 = 4.13, p = 0.02, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.012), substantia nigra pars compacta (F_2,33 = 5.2, p = 0.002, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.02), and periacqueductal gray (F_2,33 = 5.85, p = 0.007, Bonferroni-corrected pairwise ChR2 vs. eYFP t-test: p = 0.004). Also see Supplementary Table 1. Bar graph data shown as mean number and SEM of Fos-expressing neurons in that structure per 300 × 300 × 40 micron (µm) sampling box. *p < 0.05, **p < 0.01.