Electrodes in the brain may make Star Trek-style mind melds a reality!

LOS ANGELES, Kalifornia (PNN) - December 22, 2015 - From the Vulcan mind meld to Professor Dumbledore's Pensieve, there are countless ways in which people share memories in fictional films and TV shows.

But such fantastical ideas could soon become a reality, using electrodes implanted in the brain.

Neuroscientists have already begun trialing implants that boost memory loss, and in the future they believe these implants could be used to replicate memories in the brains of others.

Research teams from the University of Southern Kalifornia and University of Pennsylvania have been testing the technology on epilepsy patients.

These patients already have electrodes implanted in their brains, which means the experts didn't need to insert the prostheses in new patients through risky brain surgery.

The research centered on the hippocampus, a seahorse-shaped part of the brain associated with the formation of memories.

The hippocampus gathers sensory information that is then transformed into short-term memories, between 15 and 30 seconds.

These can then form more lasting memories, but only if they are accessed while the hippocampus is storing them.

People with significant memory deficits typically have a damaged hippocampus.

The USC team, led by brain implants expert Ted Berger, was interested in two particular areas of the hippocampus, called CA3 and CA1.

In particular, the team thought that an electrical signal traveling from CA3 to CA1 was key to memory formation.

Therefore, they tried to recreate a similar signal in order to restore the hippocampus' functionality.

To do this, the researchers monitored the brain of 12 epilepsy patients performing a memory exercise that included memorizing pictures to see how CA3 and CA1 interacted.

Eventually, they developed a mathematical model to predict the pattern of the signal CA3 would fire to CA1. The predictions were correct 80% of the time.

The USC team's idea is that brain implants could provide electrical stimulation resembling that key CA3 signal to improve memory in patients with hippocampus damage.

The work builds on a previous study carried out by Dr. Berger in which his team taught rats to learn a task, pressing one lever rather than another to receive a reward.

Using embedded electrical probes, they recorded changes in the rat's brain activity between the two major internal divisions of the hippocampus.

During the learning process, the hippocampus converts short-term memory into long-term memory.

Dr. Berger said, “No hippocampus, no long-term memory, but still short-term memory.”

Researchers blocked the normal neural interactions between the two areas using pharmacological agents, leaving the rats no longer displaying the long-term learned behavior.

“The rats still showed that they knew when you press left first, then press right next time, and vice-versa,” said Dr. Berger. “They still knew in general to press levers for water, but they could only remember whether they had pressed left or right for five to ten seconds.”

Using a prosthetics model, the researchers then developed an artificial hippocampal system that could duplicate the pattern of interaction between the two internal divisions of the hippocampus.

Long-term memory capability returned to the pharmacologically blocked rats when the team activated the electronic device programmed to duplicate the memory-encoding function.

In addition, the researchers went on to show that if a prosthetic device and its associated electrodes were implanted in animals with a normal, functioning hippocampus, the device could actually strengthen the memory being generated internally in the brain and enhance the memory capability of normal rats.

Researchers from the University of Pennsylvania have also been using brain-embedded electrodes, but in a slightly different way.

Rather than targeting specific hippocampus areas, the researchers instead zap the whole brain section close to the hippocampus, named the medial temporal lobe.

Stimulating this zone can boost memory in patients who struggle with recalling; however, it can actually worsen memories in healthy people.

For this study, the team monitored the brain activity of 28 people with epilepsy while they performed memory tasks.

They then created an algorithm that analyzed brain signals to predict when each of the participants was likely to forget a given bit of information.

The Pennsylvania team said that firing the electrodes during a period when the patient was likely to forget could boost memory by 140%.

They are currently seeking approval to carry out experiments with more specific implants.