Physicists have created the first synthetic analogue of the synapse of nerve cells

© Illustration RIA Novosti . Alina Planinata the artist imagined the transmission of signals across synapses of nerve cellsPhysicists have created the first synthetic analogue of the synapse of nerve cells© Illustration RIA Novosti . Alina Polyanina

American scientists have developed the first solid-state analogue of the synapse connections between nerve cells that allows scientists to create computing systems that simulate the brain, and to study its mysteries in the «hardware», reads the article published in the journal ACS Nano.

«The main feature of synapses is that they can simultaneously transmit both the excitatory and inhibitory signals to other nerve cells. All attempts to copy them to the device require the use of about 10-20 transistors, the combination of which allows to simulate only one nerve ending. The human brain is, in turn, contains 100 trillion synapses,» says Wang Han (Han Wang) from the University of southern California in San Francisco (USA).

The synapses or nerve endings are special structures on the surface of nerve cells that allow them to transmit information in the form of electrical and chemical signals to nearby neurons, sharing with them special molecules-neurotransmitters. In the brain cells of humans and animals contains many such substances, some of which excite neurons, making them more likely to develop signals, others inhibit their work.

In the synapses there are many «bags» with similar substances which they transmit in connected with them a neuron when receiving corresponding commands in the nerve cell from other cells, associated with her own nerve endings. As recently discovered by scientists, these neurons, unlike transistors and man-made analogues of nerve cells, can simultaneously transmit and inhibitory and excitatory signals and «switch» between different modes, which gives them incredible flexibility.

Wang and his colleagues created the first fully-fledged analogue of the synapse, bringing a kind of sandwich of several pieces of different semiconductors, the so — called black phosphorus selenide and tin, as well as two gold contact pads and the substrate of silicon dioxide.

A key part of this artificial synapse — thin layer of phosphorus oxide, phosphoric separating the semiconductor and the substrate, as they say scientists, it may seem to many researchers is a mistake or defect in production, because such layers are usually formed by poor insulation of the circuits and at their contact with air during manufacture.

In fact, this part of the sandwich Wang and his colleagues allows him to switch between different modes of operation, passing or not passing current when the electric field to one or two gold electrodes. How much current flows, this layer can be flexibly changed using the electrodes, which allows to mimic the operation of synapses and nerve cells in General.

Accordingly, the combination of a large number of such artificial nerve endings can be used not only for the creation of artificial neural networks, without spending a huge amount of transistors, or computing resources, but also to create analogues of the brain and the chain of neurons of living things and exploring how they work. This, as scientists hope, will bring us closer to uncovering the mysteries of human consciousness.

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