Photomicrographs of nissl-stained sections through the amygdala, superior colliculus (SC), and pulvinar. Panel (A) shows the location of panels (B–F) within the brain. Amygdala nuclei (B) are outlined and labeled according to Amaral et al. (). AB, accessory basal; B, basal; L, lateral; M, medial; PL, paralaminar. SC nuclei (C) are outlined and labeled according to May (). SZ/SGS, stratum zonale/stratum griseum superficiale; SO, stratum opticum; SGI/SAI, stratum griseum intermedium/stratum album intermedium; SGP, stratum griseum profundum; SAP, stratum album profundum. Thalamic nuclei (D–F) are outlined and labeled according to the delineations of the Olszewski (). CM, centromedial nucleus; H, habenula; L, nucleus limitans; LGN, lateral geniculate nucleus; LP, lateral posterior nucleus; MD, mediodorsal nucleus; MG, medial geniculate nucleus; PI, inferior pulvinar; PL, lateral pulvinar; PM, medial pulvinar; PO, oral pulvinar; SG, suprageniculate nucleus; VPL, ventroposteriolateral nucleus.

Tracer injections localized in SC and amygdala. Injection sites for cases Y1 (A), Y2 (B), S1 (C), and S2 (D). Each injection site is shown (in gray) on drawings of coronal sections through a standardized rhesus macaque atlas at the level of the amygdala (1st column) and the SC (2nd column). Images on the right show photomicrographs of the fluorescent tracer injections in amygdala (choleratoxin B (CTB); 3rd column; scale bar = 5 mm) and SC (fluoroemerald (FE); 4th column; scale bar = 1 mm).

Pattern of overlapping label in Case Y1. Each panel (A–D) presents a plot of labeled cell bodies or fibers from different rostro-caudal levels through the pulvinar. Anterograde label (putative axons) after injection of FE in the SC are shown in cyan. Retrograde label (cell bodies) after injection of CTB in the amygdala are shown in red. Abbreviations for thalamic nuclei are as in Figure .

Pattern of overlapping label in Case Y2. Each panel (A–D) presents a plot of labeled cell bodies or fibers from different rostro-caudal levels through the pulvinar. Anterograde label (putative axons) after injection of FE in the SC are shown in cyan. Retrograde label (cell bodies) after injection of CTB in the amygdala are shown in red. Abbreviations for thalamic nuclei are as in Figure .

Pattern of overlapping label in Case S1. Each panel (A,B) presents a plot of labeled cell bodies or fibers from different rostro-caudal levels through the pulvinar. Anterograde label (putative axons) after injection of FE in the SC are shown in cyan. Retrograde label (cell bodies) after injection of CTB in the amygdala are shown in red. Abbreviations for thalamic nuclei are as in Figure . Br, brachium of the superior colliculus.

Pattern of overlapping label in Case S2. Each panel (A–C) presents a plot of labeled cell bodies or fibers from different rostro-caudal levels through the pulvinar. Anterograde label (putative axons) after injection of FE in the SC are shown in cyan. Retrograde label (cell bodies) after injection of CTB in the amygdala are shown in red. Abbreviations for thalamic nuclei are as in Figure .

Colocalization of retrograde and anterograde labeling in the pulvinar. FE-labeled fibers resulting from injection into the SC are shown in cyan. CTB-immunoreactive cell bodies resulting from injection into the amygdala are shown in red. Atlas pictures are included to illustrate where each photo was taken. The case from which the images are derived is shown in the upper right corner. (A) Images of cells within PM, case Y1. Atlas image is shown in (A1). Low power confocal image (20× magnification, (A2)) showing a band of labeled cell bodies (red) within the field of labeled axons running along the medial boundary of the PM, parallel to the brachium of the SC. Atlas image is shown in (B1). Chevrons indicate cell bodies. Panels (A3,A4) are higher power (60×) magnifications of the areas indicated by boxes in (A2). (B) Images of cells within PI, case Y2. Atlas image is shown in (B1). Low power (20×, (B2)) confocal image showing colocalization of labeled cell bodies and axons in PI. Chevrons indicate cell bodies. Panels (B3, B4) show high power (60×) magnification. As in (A), chevrons in B3 and B4 indicate areas of overlap in labeled cell bodies and axons. (C) Cells within PO, case Y1. Atlas image shown in (C1). High power (63×) confocal image showing individual cell bodies and finer axonal processes in close proximity in (C2). (D) Cells within PO, case S2. Atlas image shown in (D1). High power (63×) confocal image in (D2). Arrows indicate close associations between labeled terminal boutons and labeled cells. Scale bars are as indicated in each panel.