Definition: The limbic system is a group of structures in the brain associated with emotions and drives. It is made up of four main structures: the amygdala, the hippocampus, regions of the limbic cortex and the septal area. These structures form connections between the limbic system and the hypothalamus, thalamus and cerebral cortex. The hippocampus is important in memory and learning, while the limbic system itself is central in the control of emotional responses.
The limbic system is associated with a number of functions including the sense of smell, behavior, learning, long-term memory, emotions and drives. The word limbic comes from the Latin word limbus, which roughly means "belt" or "border." This system is shaped somewhat like a doughnut and forms an inner border to the cortex. Learn more about the limbic system.