Combinatorial Inputs to the Ventral Striatum from the Temporal Cortex, Frontal Cortex, and Amygdala: Implications for Segmenting the Striatum

Temporal pole, adjacent areas, and medial temporal cortex. Coronal slices of areas and structures within TP+ stained with WFA (A) or NeuN (B). C, D, Sagittal slices of TP+ stained with PV. Slice locations for A–D shown in inset of A. Coronal slices of the anterior MTC (E) and posterior MTC (F) stained with NeuN. G, Orbital view of temporal lobe showing schematic of 11 anterograde injections placed in TP+ (area TG, TEr) and MTC (EC, 36, TH, TL/TF, TF). Lines indicate slice locations for E, F. Short black lines in A–F and dashed lines in G indicate areal boundaries. Am, amygdala; CA, cornu ammonis; Hip, hippocampus; LI, limen insula; PaS, parasubiculum; ProS, prosubiculum; S, subiculum; acf, anterior calcarine fissure; amts, anterior middle temporal sulcus; ots, occipital temporal sulcus; rs, rhinal sulcus; sts, superior temporal sulcus.

Temporal inputs to the striatum: anterograde labeling. Anterograde tracer injections in the TP (A), TEr in the rostral inferior temporal cortex (B), and the anterior (C, D) and posterior (E, G) MTC show three broad patterns (red, green, cyan) of dense terminal projections in the striatum. Note the split in projections from MTC to the dorsal and ventral striatum.

MTC projections to the striatum. 3D model of aggregate striatal projections (cyan) from anterograde injections in the anterior and posterior MTC (EC, areas 36, TH, TL/TF, and TF). Note the split in projections to the dorsal and ventral striatum and their convergence in the rostral pole of the caudate.

Temporal inputs to the striatum: retrograde labeling. Coronal sections of TP+ and MTC from four tracer injections in the VS (A–D) and two injections in the dorsal caudate (E, F). All parts of the VS receive strong projections from the TP and MTC. Rostral inferior temporal cortex (area TEr) sends projections primarily to the VSv and central and lateral VSd.

Overlap of temporal, frontal, and amygdala projections in the striatum. Outlines (black) of dense projections from TP+ and MTC are overlaid on schematic composites of dense projections (filled) from various frontal regions. Temporal injection sites shown above. Ca, caudate; Pu, putamen; NAc, nucleus accumbens.

Frontal and amygdala inputs to the striatum: retrograde labeling. A–D, Four retrograde tracer injections in VS. E, One injection in the rostral dorsal caudate. Coronal sections of the frontal cortex (i, ii) and amygdala (iii). AB, accessory basal nucleus; B, basal nucleus; L, lateral nucleus. Aiii, Ciii, and Diii are reprinted with minor stylistic edits from Fudge et al. (2002) with permission from Elsevier, Inc.