Ventricles
The ventricles are four interconnected cavities distributed throughout the brain that produce and contain cerebrospinal fluid (CSF).
1) Start with this video:
2) Then, read this article: Know Your Brain - Ventricles
3) Watch this video to learn about hydrocephalus, a condition characterized by enlargement of the ventricles:
4) Finally, answer these questions to test your understanding:
1. The ventricles of the brain primarily function in the production and circulation of:
- A. dopamine
- B. cerebral blood
- C. melatonin
- D. cerebrospinal fluid
Show Answer
Correct answer: D
The ventricles are a network of cavities distributed throughout the brain. Their primary role is in the production and circulation of cerebrospinal fluid.
2. Which specialized structure(s) in the brain’s ventricles is responsible for producing cerebrospinal fluid (CSF)?
- A. arachnoid villi
- B. blood-brain barrier
- C. choroid plexus
- D. interthalamic adhesion
Show Answer
Correct answer: C
The choroid plexus is a network of specialized cells inside the brain’s ventricles. It is made up of ependymal cells and a rich network of blood capillaries, which work together to filter blood plasma and secrete CSF.
3. A tumor causes the cerebral aqueduct to become blocked, allowing very little cerebrospinal fluid to flow through it. What ventricle or ventricles will likely become enlarged, potentially resulting in hydrocephalus?
- A. only the lateral ventricles
- B. only the third ventricle
- C. the third ventricle and both lateral ventricles
- D. all four ventricles (both lateral, third, and fourth)
Show Answer
Correct answer: C
The cerebral aqueduct connects the third ventricle with the fourth ventricle. Cerebrospinal fluid (CSF) is produced in all of the ventricles and flows out through the fourth ventricle into the subarachnoid space. If the cerebral aqueduct is blocked, CSF would continue to be produced in the lateral and third ventricles, but it would have no way of reaching the fourth ventricle to exit the ventricular system. Thus, it would accumulate in the third ventricle and both lateral ventricles.
4. A child is born with a congenital defect that blocks the right interventricular foramen. Which ventricle or ventricles would enlarge due to cerebrospinal fluid buildup?
- A. the right lateral ventricle
- B. both lateral ventricles
- C. the third ventricle
- D. the fourth ventricle
Show Answer
Correct answer: A
Obstruction of the right interventricular foramen prevents cerebrospinal fluid from flowing from the right lateral ventricle into the third ventricle. As a result, cerebrospinal fluid accumulates proximal to the blockage, causing enlargement of the right lateral ventricle only, while the other ventricles remain normal in size.
5. How is hydrocephalus typically treated?
- A. With drugs that increase the production of cerebrospinal fluid (CSF)
- B. With a device called a shunt that drains CSF from the ventricles
- C. By reducing fluid intake to reduce the amount of CSF produced
- D. There is no accepted treatment for hydrocephalus
Show Answer
Correct answer: B
A cerebral shunt is the most common treatment for hydrocephalus. A shunt system consists of a plastic tube connected to a valve and a catheter. One end of the catheter is placed in a ventricle where CSF is accumulating, and the other is typically placed in the abdominal cavity. The shunt diverts CSF to the abdominal cavity, where it can safely drain and be absorbed into the bloodstream.
