Neuroscience

Decoding spontaneous thoughts from the brain via machine learning

A team of researchers led by Kim Hong Ji and Woo Choong-Wan at the Center for Neuroscience Imaging Research (CNIR) within the Institute for Basic Science (IBS), in collaboration with Emily FINN at Dartmouth College, has unlocked ...

Genetics

New atlas of mRNA variants captures inner workings of the brain

Investigators at Weill Cornell Medicine have assembled the most comprehensive atlas to date of messenger RNA (mRNA) variants in the mouse and human brain. The atlas is an important new resource in understanding brain development, ...

Psychology & Psychiatry

Researchers map how the brain regulates emotions

Ever want to scream during a particularly bad day, but then manage not to? Thank the human brain and how it regulates emotions, which can be critical for navigating everyday life. As we perceive events unfolding around us, ...

Alzheimer's disease & dementia

Is your blood aging your brain? It might increase your dementia risk

By 2050, the global population of adults 60 and older will approximately double, leading to upward of 153 million dementia cases. That's why University College Cork neuroscience professor Yvonne Nolan and Ph.D. student Sebastian ...

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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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