Division
Cerebellar vermis
Also called Cerebellar vermis
The worm-shaped middle strip of the cerebellum, keeping your body balanced and upright.
The vermis is the narrow, ridged strip running down the middle of the cerebellum, between its two big halves. It looks a bit like a curled-up worm, which gave it its name. It controls the middle of your body: posture, balance and the rhythm of walking. It also helps aim your quick eye movements.
Where it is
Right down the middle of the cerebellum, where its left and right halves meet, at the back of the head.
What it does
Posture and balance
It keeps your trunk upright and steady whether you are standing, sitting or bending.
Walking
It helps blend the swing of your legs and the sway of your body into a smooth walk.
Aiming the eyes
Part of it makes sure your quick eye jumps land exactly on target.
Links to feelings
Through the fastigial nucleus, it connects with emotion circuits, a role scientists are still exploring.
Think of it as the spine of a book: the thin middle part that joins the two halves and keeps the whole thing standing straight.
Works with
- Fastigial nucleusThe vermis sends its signals out through this deep nucleus to the brainstem.
- Spinal cordIt gets constant updates from the spinal cord about the position of your trunk and legs.
- Medulla oblongataIts output reaches balance and posture centers in the lower brainstem, which then steer your muscles.
- Flocculonodular lobeIts lowest tip, the nodulus, belongs to this balance-focused lobe.
- Anterior lobe of the cerebellumIts upper part runs through the anterior lobe and shares its job of keeping your walk steady.
When it goes wrong
Wobbly trunk
Damage here makes it hard to sit or stand still without swaying, and walking becomes wide-legged and staggering. Surprisingly, the hands may still work well.
Alcohol damage
Long-term heavy drinking often damages the upper front part of the cerebellum, including this strip, which is why a wide, unsteady walk is a common sign.
A childhood brain tumor
Medulloblastoma, the most common cancerous brain tumor in children, often starts in or near the vermis. Many children with it can now be treated successfully.
For learning only, not medical advice. If you have a health concern, talk to a doctor.
Surprising facts
- Walking heel-to-toe in a straight line is a quick bedside test of how well the vermis is working.
Where the name comes from
Latin for "worm". Its many small ridges make it look like a segmented worm lying between the two halves of the cerebellum.
Learn it in a lesson
- The cerebellumSmooth, balanced, well-timed movement. A short guided lesson in 3D.
Quick quiz
3 questions. Your answers are saved and come back in your daily review.
Which of these is a job of the vermis?
Show the answer
Posture and balance. It keeps your trunk upright and steady whether you are standing, sitting or bending.
Posture and balance. It keeps your trunk upright and steady whether you are standing, sitting or bending.
The vermis is part of which larger structure?
Show the answer
Cerebellum. It belongs to the cerebellum.
Cerebellum. It belongs to the cerebellum.
Which part fits this description? "Like the spine of a book: the thin middle part that joins the two halves and keeps the whole thing standing straight."
Show the answer
Vermis. It is the vermis. The worm-shaped middle strip of the cerebellum, keeping your body balanced and upright.
Vermis. It is the vermis. The worm-shaped middle strip of the cerebellum, keeping your body balanced and upright.
These parts now come back in your daily review, just before you would forget them.
Practice it and its neighbors in 3DSources
- Vermis, Radiopaedia
- Neuroanatomy, Cerebellar Dysfunction, StatPearls, NCBI Bookshelf
- Medulloblastoma, StatPearls, NCBI Bookshelf
Spotted a mistake? Tell us.
Explore the cerebellar vermis in 3D
Turn it around, zoom inside and see how it connects to the rest of the brain, then test yourself with quick quizzes.
Open it in 3D