adhd and the cerebellum

Although the specific cause of ADHD is unknown, what is known is that there is a link between ADHD and the cerebellum because brain scans reveal that many children who have ADHD have cerebellums that are under-developed. The human cerebellum constitutes about 10 percent of the brain’s size, but because it has so many densely packed neurons, the cerebellum actually has more neurons than the rest of the brain. It is about the size of a plum, yet has two hemispheres and ten lobes. The complexity of the structure is reflected in the meaning of the word “cerebellum,” which means “little brain.”

The cerebellum has a number of responsibilities. It is primarily responsible for coordinating motor activities such as posture, balance, coordination and eye movement. More specifically, it calibrates motor activity, including motor movements controlled by other areas of the brain. In that regard, it works closely with the inner ear and the vestibular system to fine-tune incoming sensorimotor information. People who have damaged or under-developed cerebellums have less calibrating ability, and as such, can show slow or erratic movements. The cerebellum is also believed to play a role in language, mental imagery, attention and learned sequences of movements. Functional brain scans reveal that the cerebellum shows activity during these tasks.

The relationship between ADHD and the cerebellum has to do with an inadequate relay of information. Because the ability adhd and the cerebellumof the cerebellum to relay sensorimotor information to other parts of the brain and process incoming sensory information to the brain is diminished or distorted, children with ADHD experience the typical ADHD symptoms of poor motor control, inattention, hyperactivity due to sensory overload and a host of other issues. Because of this reduced cerebellar functioning, the frontal cortex – the area most widely associated with ADHD symptoms – has to try to compensate for the poor or non-existent signals coming from the cerebellum, with obviously inadequate results.

Activity-based treatments that focus on the interaction between the vestibular system, the cerebellum and the rest of the brain have been shown to be highly successful in the treatment of ADHD and a host of other learning disabilities, including dyslexia. Such treatments seek to improve the transmission of neurons between these brain structures by tapping in to the brain’s natural ability to grow, change and become more efficient, thus overcoming the link between ADHD and the cerebellum. Additional information about activity-based treatments is available at