Israeli researchers Itay Baruchi and Eshel Ben-Jacob of Tel-Aviv University have demonstrated through experiment that it’s possible to store multiple rudimentary memories in an artificial culture of live neurons. This is a critical step towards cyborg-like integration of living material into memory chips.

To create a new memory in the neurons, the researchers introduced minute amounts of a chemical stimulant into the culture at a selected location. The stimulant induced a second firing pattern, starting at that location. The new firing pattern in the culture along coexisted with the original pattern. Twenty-four hours later, they injected another round of stimulants at a new location, and a third firing pattern emerged. The three memory patterns persisted, without interfering with each other, for over forty hours.

Their findings are published in this month’s Physical Review E journal, the abstract for which reads, “We show that using local chemical stimulations it is possible to imprint persisting (days) multiple memories (collective modes of neuron firing) in the activity of cultured neural networks. Micro-droplets of inhibitory antagonist are injected at a location selected based on real-time analysis of the recorded activity. The neurons at the stimulated locations turn into a focus for initiating synchronized bursting events (the collective modes) each with its own specific spatiotemporal pattern of neuron firing.”

In addition to producing the first chemically operated neuro-memory chip, the researchers propose that their work implies that chemical stimulation may be crucial to learning and memory formation in living organisms.