Researchers from the Autonomous University of Barcelona have developed a new material that can mimic human brain synapses. These findings may allow us to better understand the unconscious learning processes that take place as we sleep.

This breakthrough is one of the latest developments in the field of neuromorphic computing, a computation paradigm in which electrical circuits are made to imitate neurological functions. This new material is a magneto-ionic material, in which neural activities are emulated by displacing ions to change the magnetic properties of the material. An ongoing challenge in neuromorphic computing has been controlling the ion displacement and resulting magnetic changes after stopping the electrical stimulation. This makes it difficult to mimic certain brain functions, such as the unconscious learning that takes place when we are asleep, and our brains aren’t being externally stimulated.

In this case, the new material mimics neuronal plasticity, which is the brain’s ability to store or dispose of information and is linked to learning and memory. Neuronal plasticity is based on the repetition and duration of electrical impulses. This new material, made of cobalt mononitride, emulates plasticity with those same mechanisms. By submerging the material in a liquid electrolyte and then electrifying it, nitrogen ions accumulate at the barrier between the material and the electrolyte. The ions can then be controlled by changing the material’s thickness and the frequency of electrical pulses—and the ionic displacement persists even when no voltage is applied.

This advancement opens new doors for emulating a range of neural functions that we were previously unable to fully mimic. “We have developed an artificial synapse that in the future may be the basis of a new computing paradigm, alternative to the one used by current computers,” said the study authors.