The hippocampus processes, stores, and sorts memories, connecting similar ones and giving them meaning. Memories are stored throughout the brain in neuron networks. Working memory in the frontal lobe examines new information to determine if it should be saved or discarded. Short term memories last a short time unless rehearsed, at which point they may become long term memories through the process of consolidation over several hours as the brain strengthens connections between neurons. Consolidating memories is easier during sleep when the brain has fewer competing stimuli.