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

June 30, 2026

A common brain protein may be giving Alzheimer’s disease an unexpected way to spread, carrying toxic Tau proteins from damaged neurons into healthy ones. By blocking these harmful protein packages before they reach new cells, researchers believe ...
Creatine is best known as a muscle-building supplement, but scientists are now investigating whether it could also help treat depression by boosting the brain's energy supply. A new review examined five randomized clinical trials involving 238 ...
A new stem-cell-inspired technique allows scientists to grow vast numbers of immune-cell progenitors that can be engineered to hunt cancer and strengthen immune responses. In animal studies, the ...
Researchers tested experimental PCAI compounds against pancreatic cancer cells and found they had powerful anticancer effects. One leading compound blocked more than 90% of cancer cell migration, ...
Fish oil supplements successfully delivered omega-3s to the brain, but a two-year study found no meaningful benefits for memory, cognition, or Alzheimer’s-related brain changes. The results ...
Scientists have uncovered a surprising clue that may help explain why multiple sclerosis (MS) progresses rapidly in some people but not others. In brain tissue from patients with severe MS, researchers found large numbers of “foamy” immune cells ...
A six-month study of more than 120 adults in their 70s found that high-intensity interval training (HIIT) may offer a key advantage over other forms of exercise: it helped reduce body fat while preserving valuable muscle mass. While moderate and ...
Scientists at UCLA have linked long-term exposure to the pesticide chlorpyrifos with a sharply increased risk of Parkinson’s disease. People exposed to the chemical near their homes were more than ...
Teens who use cannabis may face a substantially greater risk of developing serious mental health conditions, including psychotic and bipolar disorders, according to a study of more than 463,000 ...
Researchers have identified a vitamin B12–based compound that can cross the blood-brain barrier and home in on glioblastoma tumors. In animal studies, the compound accumulated preferentially in tumor tissue and delivered sustained nitric oxide ...
Aging may trigger the appearance of specialized stem cells that supercharge the body's ability to create new belly fat. The discovery reveals a potential biological driver of middle-age weight gain and a promising target for future anti-obesity ...
The battle between butter and margarine comes down to chemistry. Butter’s naturally occurring fats create rich flavors, golden browning, and flaky baked goods, while margarine’s modified plant oils offer consistency and a longer shelf life. ...

Latest Headlines

updated 12:56 pm ET