Which brain structure is referred to as the "little brain"?

The cerebellum is referred to as the "little brain" due to its distinct structure and size compared to the larger cerebrum. This part of the brain is located underneath the cerebrum and is involved primarily in coordinating voluntary movements, balance, and motor control. It is essential for fine-tuning motor activities and helps in maintaining posture and equilibrium. Additionally, the cerebellum plays a role in certain cognitive functions and emotional processing.

In contrast, other structures like the cerebrum are much larger and responsible for higher-level functions such as thought, memory, and decision-making. The brain stem is crucial for regulating basic life functions such as heartbeat and breathing, while the medulla oblongata is a specific part of the brain stem that governs autonomic functions. Each of these structures has its specific roles, but it is the cerebellum that is notably recognized for its smaller size and essential functions related to movement and balance, thereby earning the nickname "little brain."