Neuroscience

Movement information offers critical visual cues

Most research studies use pictures to explore how the brain constructs what we 'see,' but, we do not live in a static world. Motion cues offer a rich source of untapped information that can be beneficial in understanding ...

Neuroscience

Portable cap can measure cognition with pulsed laser light

Measuring activity in the human brain remains one of the greatest challenges in science and medicine. Despite recent technological advances in areas such as imaging and nanoscience, researchers still struggle to accurately ...

Psychology & Psychiatry

Abnormal 12-hour cyclic gene activity found in schizophrenic brains

Researchers at the University of Pittsburgh School of Medicine, U.S. present the first evidence of 12-hour cycles of gene activity in the human brain. Published in the open access journal PLOS Biology on January 24, the study ...

Neuroscience

Pop-up electrode device could help with 3D mapping of the brain

Understanding the neural interface within the brain is critical to understanding aging, learning, disease progression and more. Existing methods for studying neurons in animal brains to better understand human brains, however, ...

page 1 from 40

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.

This text uses material from Wikipedia, licensed under CC BY-SA