The Cerebellum
The cerebellum, is the smaller wrinkled, cauliflower shaped halves to the rear of the brain and often called “the little brain” as closely resembles the cerebrum above it. Like the cerebrum the cerebellum has a cortex. It is the second largest part of the brain accounting for a tenth of the brain’s total weight. The cerebellum controls precise coordinated movements like playing the guitar or climbing a ladder. It learns and fine tunes movements as well. It is linked to the spinal cord, muscles of the body below it, to the diencephalon, and to the cerebrum. To make the body move the cerebrum sends nerve signals from its motor center to the cerebellum. The signal travels from the cerebellum and to the muscles that need to move along nerves. The nerve signals make the muscles act as instructed. Proprioceptors in the muscles detects the shortening and lengthening of the muscles and the bending and straightening of the joints as well as the body’s posture and balance. The proprioceptors send this information or feedback return to the cerebellum using sensory signals along sensory nerves. The cerebellum takes the feedback and compares it the movements that occurred to the original instructions sent to the muscles. The cerebellum makes an assessment of the progress of movement detecting any differences or problems along with any necessary corrections. This assessment information is sent to the cerebrum so that the motor center can adjust the body as it continues to move. Although this process is lengthy in explanation, it happens many times every second to give humans precisely coordinated, well balanced action. (Farley et al., 2014) (Roca & Serrano, 1996) (Olesky, 2001) (Parker, 1997) (Walker & Wood, 2003).