Diseases, Conditions, Syndromes

Neuropeptide reduces epileptic seizures in human brain tissue

One challenge facing researchers who study brain diseases is that for understandable reasons it is difficult to obtain human brain tissue for experiments. For that reason, experimental models are used, such as rodent studies, ...

Neuroscience

A molecular map of the brain's decision-making area

Researchers at Karolinska Institutet have come one step closer toward understanding how the part of our brain that is central for decision-making and the development of addiction is organized on a molecular level. In mouse ...

Oncology & Cancer

New software tool uses AI to help doctors identify cancer cells

UT Southwestern researchers have developed a software tool that uses artificial intelligence to recognize cancer cells from digital pathology images—giving clinicians a powerful way of predicting patient outcomes.

Neuroscience

Imaging reveals pathways behind depression

MRI illuminates abnormalities in the brains of people with depression, potentially opening the door to new and improved treatments for the disorder, according to two studies presented this week at the annual meeting of the ...

Oncology & Cancer

New strategy for treating the most aggressive type of brain cancer

Researchers from the University of São Paulo (USP) in Brazil have developed a strategy for treating the most aggressive type of brain cancer in adults that combines a photoactive molecule and a chemotherapeutic agent—both ...

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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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