News tagged with human brain

Related topics: brain , genes , brain cells , neurons , neuroscientists

Where will big neuroscience take us?

We're entering the era of big neuroscience. In a little over a year, the United States, Europe, Japan and Israel have launched brain research projects with big budgets and bold ambitions. Several other countries ...

Nov 17, 2014
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Fruit fly lights up brain wiring

(Medical Xpress)—Fluorescent fruit flies have helped University of Queensland researchers take a critical step toward understanding the human brain's neuronal "wiring" and how it can go awry.

Oct 30, 2014
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New knowledge about the human brain's plasticity

The brain's plasticity and its adaptability to new situations do not function the way researchers previously thought, according to a new study published in the journal Cell. Earlier theories are based on lab ...

Nov 06, 2014
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ASU engineer examines brain's inner workings

Deeper understanding of the workings of the human brain will almost certainly open doors to significant medical advances. Gaining that knowledge hinges to a large degree on finding new ways to peer closer ...

Nov 07, 2014
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Researchers observe brain development in utero

New investigation methods using functional magnetic resonance tomography (fMRT) offer insights into fetal brain development. These "in vivo" observations will uncover different stages of the brain's development. ...

Oct 27, 2014
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Human brain

The human brain is the center of the human nervous system and is a highly complex organ. Enclosed in the cranium, it has the same general structure as the brains of other mammals, but is over three times as large as the brain of a mammal with an equivalent body size. Most of the expansion comes from the cerebral cortex, a convoluted layer of neural tissue that covers the surface of the forebrain. Especially expanded are the frontal lobes, which are involved in executive functions such as self-control, planning, reasoning, and abstract thought. The portion of the brain devoted to vision is also greatly enlarged in humans.

Brain evolution, from the earliest shrewlike mammals through primates to hominids, is marked by a steady increase in encephalization, or the ratio of brain to body size. The human brain has been estimated to contain 50–100 billion (1011) neurons[citation needed], of which about 10 billion (1010) are cortical pyramidal cells.[citation needed] These cells pass signals to each other via approximately 100 trillion (1014)[citation needed] synaptic connections.

In spite of the fact that it is protected by the thick bones of the skull, suspended in cerebrospinal fluid, and isolated from the bloodstream by the blood-brain barrier, the delicate nature of the human brain makes it susceptible to many types of damage and disease. The most common forms of physical damage are closed head injuries such as a blow to the head, a stroke, or poisoning by a wide variety of chemicals that can act as neurotoxins. Infection of the brain is rare because of the barriers that protect it, but is very serious when it occurs. More common are genetically based diseases[citation needed], such as Parkinson's disease, multiple sclerosis, and many others. A number of psychiatric conditions, such as schizophrenia and depression, are widely thought to be caused at least partially by brain dysfunctions, although the nature of such brain anomalies is not well understood.

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