Amygdala interconnections with the cingulate motor cortex in the rhesus monkey.

Amygdala interconnections with the cingulate motor cortices were investigated in the rhesus monkey. Using multiple tracing approaches, we found a robust projection from the lateral basal nucleus of the amygdala to Layers II, IIIa, and V of the rostral cingulate motor cortex (M3). A smaller source of amygdala input arose from the accessory basal, cortical, and lateral nuclei, which targeted only the rostral region of M3.

Neurotrophic factors in the central nucleus of amygdala may be organized to provide substrates for associative learning.

The central nucleus of amygdala was examined to identify the ultrastructural distribution of neurotrophins responsible for the complex of neuronal signaling processes which regulate synaptic transmission and neuronal plasticity, and possibly underlie memory formation. We investigated at the electron microscopic level the cellular organization of brain-derived neurotrophic factor (BDNF) and its receptor, tyrosine kinase receptor B (TrkB), in the extended amygdala (CE). We also investigated the interaction between cortical inputs to CE and BDNF and TrkB.

Cytoarchitecture and cortical connections of the posterior cingulate and adjacent somatosensory fields in the rhesus monkey.

The cytoarchitecture and connections of the caudal cingulate and medial somatosensory areas were investigated in the rhesus monkey. There is a stepwise laminar differentiation starting from retrosplenial area 30 towards the isocortical regions of the medial parietal cortex. This includes a gradational emphasis on supragranular laminar organization and general reduction of the infragranular neurons as one proceeds from area 30 toward the medial parietal regions, including areas 3, 1, 2, 5, 31, and the supplementary sensory area (SSA).