News tagged with brain

Related topics: neurons , brain activity , brain regions , brain cells , nerve cells

How do anorexics control their appetite?

Many adults, regardless of their weight, resolve to avoid fatty foods and unhealthy desserts. But despite one's best intentions, when the moment for decision comes, that chocolate lava cake is often too enticing and self-control ...

Mar 23, 2015
popularity 19 comments 2

Brain fitness for a long and healthy life

The strategies for living a long and healthy life are well known and relatively simple, if not always easily executed: Maintain an appropriate weight. Eat the right foods. Exercise. Limit stress.

Mar 23, 2015
popularity 44 comments 0

Brain activity during cardiac arrest

All over the world, researchers are trying to solve an age-old mystery: What happens in the brain when the heart stops? With the support of the Austrian Science Fund FWF, medical experts from Vienna are participating ...

Mar 23, 2015
popularity 35 comments 0

Milk could be good for your brain

New research conducted at the University of Kansas Medical Center has found a correlation between milk consumption and the levels of a naturally-occurring antioxidant called glutathione in the brain in older, ...

Mar 24, 2015
popularity 50 comments 0

Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as jellyfish and starfish have a decentralized nervous system without a brain, while sponges lack any nervous system at all. In vertebrates, the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, balance, taste, and smell.

Brains can be extremely complex. The cerebral cortex of the human brain contains roughly 15-33 billion neurons depending on gender and age, linked with up to 10,000 synaptic connections each. Each cubic millimeter of cerebral cortex contains roughly one billion synapses. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body and target them to specific recipient cells.

The most important biological function of the brain is to generate behaviors that promote the welfare of an animal. Brains control behavior either by activating muscles, or by causing secretion of chemicals such as hormones. Even single-celled organisms may be capable of extracting information from the environment and acting in response to it. Sponges, which lack a central nervous system, are capable of coordinated body contractions and even locomotion. In vertebrates, the spinal cord by itself contains neural circuitry capable of generating reflex responses as well as simple motor patterns such as swimming or walking. However, sophisticated control of behavior on the basis of complex sensory input requires the information-integrating capabilities of a centralized brain.

Despite rapid scientific progress, much about how brains work remains a mystery. The operations of individual neurons and synapses are now understood in considerable detail, but the way they cooperate in ensembles of thousands or millions has been very difficult to decipher. Methods of observation such as EEG recording and functional brain imaging tell us that brain operations are highly organized, but these methods do not have the resolution to reveal the activity of individual neurons.

This text uses material from Wikipedia licensed under CC BY-SA