FIGURE 1.

Differential distribution of CP and CA neurons in IL. (A) Schematic depicting the injection of fluorescent retrograde tracer into the PAG. Injection locations in the PAG were confirmed in coronal slices (300 μm) visualized using both bright-field (B, top) and epifluorescence (B, bottom) imaging. (C) Schematic depicting the injection of retrograde fluorescent tracer injection into the basolateral amygdala (BLA). (D) Bright-field image (top) of coronal brain slice (300 μm) containing the BLA and the corresponding epifluorescence image (bottom) confirming the location of retrograde tracer injection. (E) At least 2 days following tracer injection, coronal slices (300 μm) containing the mPFC were prepared (left) and oriented so that the pia of the IL cortex was horizontal in the imaging chamber (right). Bright-field and epifluorescence images showing laminar location of retrogradely labeled (F) CP neurons and (G) CA neurons in IL cortex. (H) Normalized fluorescence intensity (mean ± SEM) of soma location as a function of normalized cortical distance [where pia = 0 and white matter (wm) = 1] for CP (n = 10) and CA (n = 7) neurons in IL cortex. Rostral-caudal: R↔C; dorsal-ventral: D↔V; lateral-medial: L↔M.