Table of ContentsView AllTable of ContentsAnatomyFunctionAssociated ConditionsDiagnosis
Table of ContentsView All
View All
Table of Contents
Anatomy
Function
Associated Conditions
Diagnosis
The brainstem is a stalk-like structure in thebrainthat connects a part of the brain called thecerebellumto thespinal cord.
Although small, the brainstem performs many critical functions, including controlling the heart and breathing rate, providing motor and sensory functions to the face and neck, regulating thesleep cycle, and conveying nerve signals back and forth from the brain to the rest of the body.
The article explains the anatomy and function of the brainstem and its various parts. It also describes conditions that can affect the brainstem and how they are diagnosed.
Hank Grebe / Getty Images
Anatomy and Parts of the Brainstem
The brainstem is the lowest part of the brain located towards the back of the neck. It is a stem-shaped structure roughly 3 inches in length extending from the middle of the brain to the spinal cord.
The brainstem receives blood supply from several arteries, including the vertebral arteries, basilar artery, and pontine arteries.
Parts of the Brainstem
The brainstem is composed of three main parts, each of which has specific functions.Each section serves as a nerve gateway, relaying motor and/or sensory information to and from different parts of the body.
The sections of the brainstem include the following:
What Does the Brainstem Do?
Locomotion and Coordination
All information relayed to and from the cerebellum must pass through the brainstem. The cerebellum, also known as the “little brain,” is responsible for coordinating movement, balance, andproprioception(the awareness of your body in space).
Motor and Sensory Function of the Head and Neck
The brainstem is where 10 of the 12 pairs ofcranial nervesoriginate. These nerves relay signals to and from the head and neck, enabling smell, vision, taste, swallowing, facial sensations, and the movement of the head, face, shoulder, eye, and tongue
The cranial nerves in the brainstem are distributed as follows:
Consciousness
Autonomic Functions
Reticular Activating System and Your Sleep
What Conditions Can Affect the Brainstem?
Several conditions can directly or indirectly affect the brainstem. Because the brainstem is responsible for many key functions, the list of possible symptoms is extensive, ranging from uncontrollable eye movements andvertigo(spinning sensations) to one-sided facial paralysis and loss of muscle control.
These are some of the conditions known to affect the brainstem:
Causes of Vertigo and How It Is Treated
Diagnosing Brainstem Problems
If you have symptoms of a brainstem problem, seek prompt medical attention. Your healthcare provider will take a careful medical history and perform a physical exam, including an in-office evaluation known as aneurological exam.
Eye movements are a key focus of the exam as brainstem diseases can often causediplopia(double vision),nystagmus(jumpy eye movements), ormyokymia(eyelid twitching).
Based on your history and physical, your medical provider may order tests to further evaluate your condition, including:
Summary
The brainstem is a roughly 3-inch structure in the brain that connects the cerebellum to the spinal cord. It is composed of three sections called the midbrain, pons, and medulla oblongata that regulate numerous functions in the body, including movement, coordination, balance, taste, smell, facial expression, reflexes, heart rate, breathing rate, blood pressure, and the sleep-wake cycle.
Conditions adversely affecting the brainstem include stroke, aneurysm, multiple sclerosis, brain tumors, Parkinson’s disease, Huntington’s disease, and increased intracranial pressure.
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