Limbic encephalitis refers to inflammatory disease confined to the limbic system of the brain. The cingulate cortex is usually considered part of the limbic lobe. Antidepressant treatment appears to reverse mood congruent biases in limbic, prefrontal, and fusiform areas. The hypothalamus is located below the thalamus and is part of the limbic system. Another is the Papez circuit linking the hypothalamus to the limbic lobe. The ventral striatum is believed to play a role in reward and other limbic functions. These responses are heavily modulated by dopaminergic projections from the limbic system. Learning and affective processing are the primary functions of limbic and paralimbic brain. Cortico-basal ganglia (CBG) circuits may also be impaired, contributing to "sensory, limbic and executive" features. These structures were known together as the limbic lobe. These are often memories associated with emotions derived from input from the brain's limbic system. This is the upper part of the "limbic lobe". The TrkB regulation of granule cells is important in preventing memory deficits and limbic epilepsy. There are connecting fibres that run between frontal and limbic structures. The fornix is part of the limbic system.