Encoding (storing) most forms of new memory requires the hippocampus, an area of cortex on the medial temporal lobe, and probably other brain structures. Only one functioning hippocampal area appears to be necessary for mostly normal function. The location of memory storage is unclear, but likely involves widely distributed cerebral cortical networks, probably mostly in association cortices. Memory recall appears to involve reactivation of sensory cortices in a similar pattern to what occurred during the original perception of the event. Memory loss is called amnesia. Amnesia is called anterograde if it involves the formation of new memories after a point in time, retrograde if it involves the recall of memories prior to a point in time, or mixed if it involves both. Bilateral lesions of the hippocampal areas may cause anterograde amnesia. The cerebellum and basal ganglia probably play roles in forming and storing memory of learned movements.