The pathway by which somatosensory information reaches the limbic structures in the temporal lobe known to be critical for tactile memory has not yet been identified. To trace this pathway, the anatomical connections of identified somatosensory fields lying in or near the lateral sulcus of the macaque monkey have been investigated using both anterograde and retrograde axonal transport techniques. The data show that a series of parallel tactile processing pathways converge on the insular cortex; this region, in turn, projects directly to the amygdala and indirectly to the hippocampus via the rhinal cortex, thus linking the somatosensory cortices with the limbic structures of the temporal lobe. Opiates have been shown to affect learning and memory, though the locus of this action is not yet known. Combined lesion and receptor binding studies suggest that there are opiatergic projections from the amygdala to higher order cortical sensory processing areas, like the anterior insula and orbitofrontal areas. Furthermore, metabolic studies link the level of mu receptors to the rate of protein phosphorylation in the F1 band, suggesting that opiates may help control learning-related protein phosphorylation.