Neuron and synapse-mimetic spintronics devices developed

A research group from Tohoku University has developed spintronics devices which are promising for future energy-efficient and adoptive computing systems, as they behave like neurons and synapses in the human brain.

New method to create ultrafast 3-D images of nanostructures

Lensless microscopy with X-rays, or coherent diffractive imaging, is a promising approach. It allows researchers to analyse complex three-dimensional structures, which frequently exist in nature, from a dynamic perspective. ...

New microscopy technique peers deep into the brain

In order to understand the brain, scientists must be able to see the brain—cell by cell, and moment by moment. However, because brains comprise billions of microscopic moving parts, faithfully recording their activity comes ...

New quantum material could warn of neurological disease

What if the brain could detect its own disease? Researchers have been trying to create a material that "thinks" like the brain does, which would be more sensitive to early signs of neurological diseases such as Parkinson's.

The cost of computation

For decades, physicists have wrestled with understanding the thermodynamic cost of manipulating information, what we would now call computing. How much energy does it take, for example, to erase a single bit from a computer? ...

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Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as jellyfish and starfish have a decentralized nervous system without a brain, while sponges lack any nervous system at all. In vertebrates, the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, balance, taste, and smell.

Brains can be extremely complex. The cerebral cortex of the human brain contains roughly 15-33 billion neurons depending on gender and age, linked with up to 10,000 synaptic connections each. Each cubic millimeter of cerebral cortex contains roughly one billion synapses. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body and target them to specific recipient cells.

The most important biological function of the brain is to generate behaviors that promote the welfare of an animal. Brains control behavior either by activating muscles, or by causing secretion of chemicals such as hormones. Even single-celled organisms may be capable of extracting information from the environment and acting in response to it. Sponges, which lack a central nervous system, are capable of coordinated body contractions and even locomotion. In vertebrates, the spinal cord by itself contains neural circuitry capable of generating reflex responses as well as simple motor patterns such as swimming or walking. However, sophisticated control of behavior on the basis of complex sensory input requires the information-integrating capabilities of a centralized brain.

Despite rapid scientific progress, much about how brains work remains a mystery. The operations of individual neurons and synapses are now understood in considerable detail, but the way they cooperate in ensembles of thousands or millions has been very difficult to decipher. Methods of observation such as EEG recording and functional brain imaging tell us that brain operations are highly organized, but these methods do not have the resolution to reveal the activity of individual neurons.

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