News tagged with brain

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

Medtronic spends $350M on another European deal

U.S. medical device maker Medtronic is building stronger ties to Europe, a couple months after announcing a $42.9 billion acquisition that involves moving its main executive offices across the Atlantic, where it can get a ...

7 hours ago
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Steer clear of dietary supplements for concussions: FDA

(HealthDay)— As the fall sports season starts and young players face the risk of concussions, the U.S. Food and Drug Administration warns that dietary supplements that claim to prevent, treat or cure concussions ...

11 hours ago
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Team discovers fever's origin

Fever is a response to inflammation, and is triggered by an onset of the signaling substance prostaglandin. Researchers at Linköping University in Sweden can now see precisely where these substances are produced – a discovery ...

Aug 26, 2014
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Mind over matter for people with disabilities

People with serious physical disabilities are unable to do the everyday things that most of us take for granted despite having the will – and the brainpower – to do so. This is changing thanks to European ...

Aug 26, 2014
popularity 5 / 5 (1) | comments 0

Finding keys to glioblastoma therapeutic resistance

Researchers at the University of California, San Diego School of Medicine have found one of the keys to why certain glioblastomas – the primary form of a deadly brain cancer – are resistant to drug therapy. The answer ...

Aug 26, 2014
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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