Alzheimer's disease & dementia

Risk and progression of Alzheimer's disease differ by sex

The abnormal accumulation of proteins in the brain is a biological marker for Alzheimer's disease, but the ways in which these proteins spread may help explain why the prevalence of Alzheimer's is higher in women than in ...

Alzheimer's disease & dementia

Healthy blood vessels may be the answer to Alzheimer's prevention

If you're worried about Alzheimer's disease, your best shot at prevention could be maintaining cardiovascular health through exercise and diet and staying on top of conditions such as diabetes and high blood pressure.

Alzheimer's disease & dementia

Dementia gene linked to connections in brain

Insights into how a gene that increases the risk of Alzheimer's disease disrupts brain cells have been revealed by scientists.

Psychology & Psychiatry

Physical evidence in the brain for types of schizophrenia

In a study using brain tissue from deceased human donors, Johns Hopkins Medicine researchers say they found new evidence that schizophrenia can be marked by the buildup of abnormal proteins similar to those found in the brains ...

Medical research

Advancing epilepsy treatment

Researchers at Case Western Reserve University have successfully prevented epileptic seizures in animal models by preemptively directing a low-frequency stimulus to the nerve fibers in the brain.

Neuroscience

What's the right amount of 'zapping' in epilepsy laser surgery?

There is an estimated 2.4 million people diagnosed with epilepsy each year, according to the World Health Organization. Some types of epileptic seizure can be essentially cured by open surgery for patients who don't respond ...

Oncology & Cancer

Mutations synergize in pediatric brain cancer

A new Northwestern Medicine study finds that a combination of two mutations cause a form of pediatric brain tumors to become more deadly, according to findings published in Nature Communications.

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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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