Brain

Encephalon

The largest part of the central nervous system, weighing approximately 1.4 kg in adults. It consists of the cerebrum (two hemispheres with frontal, parietal, temporal, and occipital lobes), the cerebellum, and the brainstem (midbrain, pons, medulla oblongata). Protected by the meninges and cerebrospinal fluid.

Type Organ
Body System Nervous
Body Region Brain
Latin Name Encephalon
FMA ID 50801

Function

The command center of the nervous system, responsible for processing sensory information, controlling motor functions, regulating homeostasis, and generating consciousness, thought, memory, emotion, and language.

Clinical Significance

Stroke (cerebrovascular accident) is a leading cause of disability. Traumatic brain injury ranges from concussion to severe diffuse axonal injury. Neurodegenerative diseases include Alzheimer's, Parkinson's, and ALS.

Sub-structures

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Frequently Asked Questions

What are the main parts of the brain?
The brain is divided into three main regions: the cerebrum (the largest part, responsible for higher functions such as thought, language, and voluntary movement), the cerebellum (coordinating movement and balance), and the brainstem (regulating vital autonomic functions including breathing, heart rate, and consciousness). The cerebrum is further divided into four lobes: frontal, parietal, temporal, and occipital.
How much does the brain weigh?
The adult human brain weighs approximately 1,300–1,400 grams (about 3 pounds), representing roughly 2% of body weight. Despite its small mass, it consumes approximately 20% of the body's total energy and oxygen supply. Brain volume is approximately 1,200–1,500 cubic centimeters, with considerable variation among individuals.
What is the brain protected by?
The brain is protected by the skull (cranium), three layers of membranes called meninges (dura mater, arachnoid mater, and pia mater), and cerebrospinal fluid (CSF) that cushions the brain within the subarachnoid space. The blood-brain barrier, formed by specialized endothelial cells in cerebral blood vessels, further regulates which substances can enter brain tissue.

Related Structures

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Educational Disclaimer

This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for medical decisions.

Data sources: Terminologia Anatomica, Foundational Model of Anatomy, Wikidata.