FIG 5. Schematic figure of the limbic system and its connections. The hippocampus projects to the septal nuclei and the mammillary body via the fornix. The mammillary body projects to the anterior nucleus of the thalamus via the MTT. The anterior nucleus of the thalamus projects to the cingulated cortex via the internal capsule. The cingulated cortex projects back to the hippocampus via the cingulum bundle. Both MTT lesions can interrupt the input from the hippocampus, resulting in dysfunction of the neurocircuit in the limbic system.