What is the rule of 4 simplified?

Asked by: Mrs. Else Stehr II  |  Last update: June 28, 2025
Score: 4.5/5 (60 votes)

The “rule of four” is the Supreme Court's practice of granting a petition for review only if there are at least four votes to do so. The rule is an unwritten internal one; it is not dictated by any law or the Constitution.

What is the rule of 4's?

In the rule of 4 there are 4 rules:

There are 4 structures in the 'midline' beginning with M. There are 4 structures to the side beginning with S. There are 4 cranial nerves in the medulla, 4 in the pons and 4 above the pons (2 in the midbrain).

What is the 4th cranial nerve in the brainstem?

Excerpt. The trochlear nerve is the fourth cranial nerve (CN IV) and one of the ocular motor nerves that controls eye movement. The trochlear nerve, while the smallest of the cranial nerves, has the longest intracranial course as it is the only nerve to have a dorsal exit from the brainstem.

What are four things the brain stem controls?

Your brainstem connects your brain to your spinal cord. It sits near the bottom of your brain. It helps regulate vital body functions that you don't have to think about, like breathing and your heart rate. Your brainstem also helps with your balance, coordination and reflexes.

What are the symptoms of a lesion in the brainstem?

Symptoms
  • Coordination and movement challenges, or ataxia.
  • Speech and swallowing difficulties.
  • Facial paralysis (usually on one side)
  • Vision and auditory problems.
  • Hiccups as a result of diaphragmatic spasms.
  • Breathing difficulties that can contribute to sleep issues, including sleep apnea.

The Brainstem Clinical Anatomy - Rule of 4's, midbrain, medulla, pons

21 related questions found

How serious is a lesion on the brain stem?

Your brainstem is a stalk-like structure that connects your brain to your spinal cord. Lesions on your brainstem can cause problems with your heart rhythm, breathing, blood pressure, eye alignment and more.

How do you know if something is wrong with your brain stem?

A brain stem stroke can also cause double vision, slurred speech and decreased consciousness. Only a half-inch in diameter, the brain stem controls all basic activities of the central nervous system: consciousness, blood pressure and breathing. All motor control for the body flows through it.

Can brain stem damage be repaired?

Unlike other tissues in the body, neural tissue, or the tissue that makes up the brain stem, has a limited ability to heal. While some degree of regeneration or repair can occur, it may not fully restore function, especially in cases of severe injury.

What behaviors does the brain stem control?

The brainstem is the most evolutionarily conserved structure within brain. As such, it is the control center for the autonomic nervous system, which regulates basic life-sustaining activities such as heart rate, blood pressure, and respiration.

What part of the brain controls swallowing and coughing?

The medulla is essential to survival. Functions of the medulla regulate many bodily activities, including heart rhythm, breathing, blood flow, and oxygen and carbon dioxide levels. The medulla produces reflexive activities such as sneezing, vomiting, coughing and swallowing.

What happens if cranial nerve 4 is damaged?

Effects of a Cranial Nerve 4 Palsy

Inability to move the eye down and in toward the nose. Double vision (because the two eyes are not pointed in the same direction). This double vision is vertical and torsional (tilted) Tilting of the head to compensate for the double vision.

What is the blood supply to the brainstem?

Main arterial trunks supplying the brainstem include the vertebral artery, anterior spinal artery, posterior inferior cerebellar artery, basilar artery, anterior inferior cerebellar artery, superior cerebellar artery, posterior cerebral artery, posterior communicating artery, and anterior choroidal artery.

Why is it called a pathetic nerve?

It is called so because the paralysis of this nerve causes deviation of eye making the patient do a head tilt to fuse two images (formed by the normal eye and the abnormally deviated eye) and thus giving the patient a “dejected” or “pathetic” look ! Thankfully ,this nomenclature has now been abandoned !

What is the rule of 4 in simple terms?

The “rule of four” is the Supreme Court's practice of granting a petition for review only if there are at least four votes to do so.

What is the rule of four simple terms?

On the face of it, the Supreme Court's “Rule of Four” is straightforward. Where the justices have discretion as to whether to hear an appeal, at least four of the Court's members must vote to grant a writ of certiorari, which facilitates a full review on the merits.

Why is the rule of 4 important?

The rule of four is a US Supreme Court practice that permits four of the nine justices to grant a writ of certiorari. It has the specific purpose to prevent a majority of the Court's members from controlling their docket.

What can override brainstem control?

In infants, the brainstem is not fully developed, and as such, various factors can override brainstem control of breathing. This includes factors such as hypoxemia (low oxygen levels), hypercapnia (high carbon dioxide levels), pain, fear, and anxiety.

What are 4 things the brain stem controls?

The brainstem controls numerous vital body functions (breathing, swallowing, and vasomotor control over BP). Additionally, except for vision (CN2) and smell (CN1), all of the cranial nerves originate from the brainstem.

Which part of the brain controls blood pressure?

Your medulla oblongata is the bottom-most part of your brain. Its location means it's where your brain and spinal cord connect, making it a key conduit for nerve signals to and from your body. It also helps control vital processes like your heartbeat, breathing and blood pressure.

Has anyone ever recovered from brain stem?

However, that person won't ever regain consciousness or start breathing again. Once the brain stem has permanently stopped functioning, there's no way of reversing it and the heart will eventually stop beating, even if a ventilator continues to be used.

Can the brain heal itself after lack of oxygen?

If there has only been mild or short-lived anoxia, there may well be recovery back to a normal or near normal level of functioning. However, if the anoxic injury has been more marked the outcome is less certain and there are likely to be long-term effects.

What is a vegetative state after a stroke?

They may open their eyes and sleep and breathe normally, but show no signs of awareness. This is sometimes called a vegetative state. If someone has more signs of conscious awareness, like being able to respond to a command or communicate at times, this can be called a minimally conscious state.

What does a brain stem stroke feel like?

Common Symptoms of Brainstem Stroke

Symptoms can vary depending on where the stroke occurs, but they might include problems with balance, dizziness, trouble swallowing or speaking, and weakness on one side of the body.

How to get someone out of vegetative state?

There's no treatment to make a vegetative state get better. People sometimes recover a bit on their own depending on what their original problem was and how severe it was. People don't come back to normal, but a few relearn how to talk and understand people.

What disease attacks the brain stem?

Brainstem encephalitis (BE) is a relatively rare, severe, and rapidly progressive inflammation of the brainstem. 1 This challenging entity is largely associated with infectious and autoimmune causes.