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

Brain-inspired computing for a post-Moore's Law era

Since the invention of the transistor in 1947, computing development has seen a consistent doubling of the number of transistors that can fit on a chip. But that trend, known as Moore's Law, may reach its limit as components ...

'Census' in the zebrafish's brain

The zebrafish is a master of regeneration: If brain cells are lost due to injury or disease, it can simply reproduce them—contrary to humans, where this only happens in the fetal stage. However, the zebrafish is evolutionarily ...

Lasers learn to accurately spot space junk

Chinese researchers have improved the accuracy in detecting space junk in earth's orbit, providing a more effective way to plot safe routes for spacecraft maneuvers.

Multidimensional study offers new vision for optical tech

A new design of optical chips enables light to experience multiple dimensions, which could underpin versatile platforms for advanced communications and ultra-fast artificial intelligence technologies.

How human brain development diverged from great apes

Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Institute of Molecular and Clinical Ophthalmology Basel, and ETH Zurich, Switzerland, have presented new insights into the development ...

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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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