Overview of a Stroke of the Medulla Oblongata

The medulla oblongata is a structure in the brain that transfers nerve messages from the brain to the spinal cord. It is also responsible for many involuntary functions, including:

  • Regulating blood pressure
  • Adjusting your heart function
  • Pacing your rate of breathing
  • Coordinating swallowing

A stroke in the medulla is also known as a medullary stroke. It can have devastating consequences, including death.

This article will give an overview of these strokes, including their effects, symptoms, and risk factors.

Sagittal section of the human brain, showing structures of the cerebellum, brainstem, and cerebral ventricles

Encyclopaedia Britannica / Getty Images

Location of the Medulla

The medulla oblongata is also known as the medulla. It is located at the back and the lower region of the brain and is connected to the spinal cord.

The medulla oblongata is part of the brainstem. The brainstem is composed of three sections:

  • The upper part, called the midbrain
  • The middle part, called the pons
  • The lower part, called the medulla

The medulla is located above the spinal cord and below the pons.

Stroke of the Medulla

A stroke of the medulla interferes with vital nerve messages. It can result in a number of serious problems, such as:

  • Paralysis on one or both sides of the body
  • Double vision
  • Coordination problems

A stroke involving the medulla can also interfere with your body's normal breathing and heart function. Some people who have this type of stroke may need a machine to breathe. More severe strokes in the medulla can cause "locked-in syndrome." This is a condition in which people are conscious but cannot move any part of the body except the eyes.

Symptoms of Medullary Stroke

Stroke symptoms can be hard to recognize. A stroke of the brainstem and medulla may at first cause vague symptoms, such as headaches and dizziness. The symptoms can worsen, however, and the stroke may progress rapidly.

Some of the symptoms of a medullary stroke include:

  • Severe headaches that start suddenly and get worse when you change positions, bend, strain, or cough
  • Double vision
  • Numbness in the arm, face or leg on one side
  • Weakness of the face, arm or leg on one side
  • Dizziness
  • Difficulty walking
  • Loss of balance or coordination
  • Persistent hiccups
  • Loss of consciousness

A medullary stroke can cause numbness and sensory problems on one side of the body, and weakness on the opposite side. This is unusual because most other strokes cause sensory problems and weakness on the same side of the body.

There are long nerve pathways that transmit information between the body and the brain. Many of these pathways cross over to the opposite side in the medulla. This causes the unique pattern of symptoms characteristic of medullary stroke.

Risk Factors 

Risk factors for a medullary stroke are the same as the risk factors for strokes in other areas of the brain. They include:

It is also possible for a medullary stroke to happen after a sudden head or neck movement injures an artery. This is rare, however.

Diagnosis 

A stroke in the medulla can be more difficult to diagnose than other strokes. This is because symptoms like dizziness, balance problems, and headaches are vague. Usually, a neurologist can identify a medullary stroke during a physical examination. If the symptoms are mild, however, they might not be very apparent in the early stages. 

A brain CT scan or a brain MRI can also be used to diagnose a medullary stroke. A brain MRI is usually considered a reliable test for identifying strokes in this part of the brain.

If there is concern about blood vessels or blood flow, an ultrasound or angiogram may help healthcare providers observe the blood vessels. An ultrasound uses sound waves to visualize internal structures. An angiogram uses X-rays to track how blood moves through the body.

Recovery 

Recovery from a medullary stroke depends on the size of the stroke and how quickly you were treated. Your rate of healing also plays an important role. 

Strokes of the medulla oblongata do not affect the language or thinking areas of the brain. This can make it easier for you to participate more fully in your rehabilitation.

Summary

A medullary stroke happens in the medulla oblongata, which is located on the brain stem. This part of your brain transfers messages from the brain to the spinal cord and is responsible for many of your body's involuntary functions.

A medullary stroke can cause serious symptoms like paralysis and coordination problems. In severe cases, patients may need a machine to breathe.

Symptoms can be vague at first but may progress to numbness, weakness, and loss of balance. An MRI can help your healthcare provider diagnose this type of stroke.

A Word From Verywell

Medullary strokes and other brainstem strokes are among the most difficult to recognize and diagnose. This can delay your treatment, which may be frustrating for you and your loved ones.

The outcome of a medullary stroke can vary. This is because it is a small region of the brain with many vital functions.

Frequently Asked Questions

  • Does the medulla oblongata affect your behavior?

    The medulla does not play a direct role in your behavior. Many of the functions it does control are involuntary, like breathing and heart rate. It also plays a part in coordination and balance. 

  • Is an injury to the medulla oblongata fatal?

    Not always. Some injuries to this part of the brain cause problems like numbness, poor motor control, and paralysis. Because the medulla controls critical involuntary functions like heartbeat and breathing, however, some medullary strokes can be fatal.

  • What does the medulla oblongata regulate in the body?

    The medulla oblongata sends signals from your brain to your spinal cord. It is also responsible for many of your body's involuntary functions, like heart rate, blood flow, and breathing. The medulla controls many of your reflexes, too, such as sneezing, coughing, and swallowing.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Jose Vega MD, PhD
Jose Vega MD, PhD, is a board-certified neurologist and published researcher specializing in stroke.