Exploring the neurological impact of air pollution

Air pollution has become a fact of modern life, with a majority of the global population facing chronic exposure. Although the impact of inhaling polluted air on the lungs is well known, scientists are just now beginning ...

Similar to humans, chimpanzees develop slowly

Few species develop as slowly as humans, both in terms of developing adult skills and brain development. Human infants are born so underdeveloped that they cannot survive without adult care and feeding for some years after ...

New double-contrast technique picks up small tumors on MRI

Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick ...

Determining the quantity and location of lipids in the brain

Researchers at the Beckman Institute at the University of Illinois at Urbana-Champaign have developed a new technique that can determine the specific molecular form, location, and the amount of lipids in samples of rat brain ...

Technology makes tissues elastic and lasting for easier imaging

When there's a vexing problem to be solved, people sometimes offer metaphorical advice such as "stretching the mind" or engaging in "flexible" thinking, but in confronting a problem facing many biomedical research labs, a ...

Transistor sets a new standard for energy efficiency

Smartphones, laptops and smartwatches consume vast quantities of energy, yet only around half of this energy is actually used to power important functions. And with billions of these devices in use worldwide, a significant ...

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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