New! Sign up for our free email newsletter.
Reference Terms
from Wikipedia, the free encyclopedia

Human brain

The human brain is the most complex organ in the body and the control center of the nervous system. Weighing about three pounds and composed of approximately 86 billion neurons, it governs every aspect of thought, emotion, behavior, and bodily function. Protected by the skull and suspended in cerebrospinal fluid, the brain processes sensory information, coordinates movement, regulates internal systems, and enables learning, memory, language, and consciousness.

The brain is divided into several major regions, each with specialized roles. The cerebrum, the largest part, is responsible for higher cognitive functions like reasoning, problem-solving, and voluntary movement. It is divided into left and right hemispheres and further into lobes that handle vision, touch, hearing, and decision-making. The cerebellum, located beneath the cerebrum, helps coordinate balance and precise motor control. The brainstem connects the brain to the spinal cord and regulates vital functions such as breathing, heart rate, and sleep.

The brain communicates through a vast network of neurons, which transmit electrical and chemical signals via synapses. Supporting these neurons are glial cells, which provide structural support, nutrition, and protection. This intricate system allows the brain to integrate information from the environment, make decisions, and generate responses in real time.

The human brain is also remarkably adaptable. Through a process called neuroplasticity, it can reorganize itself by forming new neural connections in response to learning, injury, or experience. This adaptability is key to development, recovery, and cognitive flexibility throughout life.

Understanding the brain remains one of science’s greatest challenges. Advances in neuroscience and neuroimaging continue to uncover how the brain functions in health and disease, offering insights into conditions such as Alzheimer’s, Parkinson’s, stroke, epilepsy, and mental illness. As research progresses, the human brain remains both a marvel of biology and a frontier of scientific discovery.

Related Stories
 


Health & Medicine News

March 14, 2026

Researchers have identified two gut bacteria that can produce serotonin, a key chemical that regulates bowel movements. In experiments with mice lacking serotonin, the microbes boosted serotonin levels, increased nerve cells in the colon, and ...
Tiny plastic particles may be quietly threatening brain health. New research suggests microplastics—now widely found in food, water, and even household dust—could trigger inflammation and damage ...
Researchers studying over 8,400 colonoscopies discovered that having both adenomas and serrated polyps in the bowel can raise the risk of serious precancerous changes by up to five times. These two polyp types may represent separate cancer pathways ...
A severe case of COVID-19 or influenza could increase the risk of lung cancer later on, according to new research. Scientists discovered that serious viral infections can alter immune cells in the lungs, leaving behind chronic inflammation that may ...
In medieval Denmark, people could pay for more prestigious graves closer to the church — a sign of wealth and status. But when researchers examined hundreds of skeletons, they discovered something unexpected: even people with stigmatized diseases ...
Scientists have discovered that a rare “mirror-image” version of the amino acid cysteine can dramatically slow the growth of certain cancers while leaving healthy cells largely untouched. Unlike ...
Researchers have discovered a surprising change in how cells produce energy in people with depression. Brain and blood cells in young adults with major depressive disorder produced more energy molecules at rest but had trouble increasing energy ...
A new study suggests Alzheimer’s disease may be detectable through subtle shape changes in proteins found in the blood. Researchers discovered that structural differences in three blood proteins closely track the progression of the disease. By ...
A newly developed antibiotic called EVG7 could offer a powerful new way to stop Clostridioides difficile, a dangerous gut bacterium that often returns after treatment. In mouse studies, researchers ...
Coenzyme A, a molecule derived from vitamin B5, is vital for metabolism throughout the body. Scientists discovered that most of it resides inside mitochondria, yet how it reached these cellular ...
Scientists have developed a promising new approach to treating Alzheimer’s disease by turning ordinary brain cells into powerful plaque-clearing machines. Instead of requiring frequent antibody infusions like current therapies, the experimental ...
A European clinical trial found that the drug sulthiame significantly reduced breathing interruptions in people with moderate to severe sleep apnea. Patients taking higher doses experienced up to 47% fewer pauses in breathing and improved oxygen ...

Latest Headlines

updated 12:56 pm ET