BRAINY goo can play a video game and learn from its own behavior, in a breakthrough poised to change the world of artificial intelligence.
Hydrogels are polymers that become flexible when hydrated, similar to the bouncy substance featured in the 1971 Robin Williams flick “Flubber.”
They are found in everyday products like hair gel and contact lenses- and they are more similar to brain cells than you’d imagine.
A study published today in the journal Cell Reports Physical Science shows how the gel can get smarter over time
Scientists at the University of Reading in the UK tasked the goo with playing Pong, one of the earliest video games consisting of a rudimentary ping-pong match.
The researchers hooked hydrogels to a virtual game environment and applied a feedback loop between the hydrogel’s paddle and the ball’s position.
They opted to use an electro-active polymer that could respond to electrical stimulation.
When the hydrogel is shocked, charged particles move inside it, dragging water molecules with them. This causes the gel to change shape.
“The rate at which the hydrogel de-swells takes much longer than the time it takes for it to swell in the first place, meaning that the ions’ next motion is influenced by its previous motion, which is sort of like memory occurring,” first author Vincent Strong explained.
“The continued rearrangement of ions within the hydrogel is based off of previous rearrangements within the hydrogel, continuing back to when it was first made and had a homogeneous distribution of ions.”
The researchers used electric signals to inform the hydrogel of the ball’s position.
They then measured the movement of charged particles, called ions, within the hydrogel to determine the position of its paddle.
The hydrogel’s accuracy improved by up to 10% after repeated trials, resulting in longer matches.
“We showed that hydrogels are not only able to play Pong; they can actually get better at it over time,” Strong said.
The scientists were inspired by an earlier study that used plated brain cells rather than brainy goo.
In that study, researchers aimed to measure if the cells could learn to play Pong if they were electrically stimulated in a way that provided feedback on their performance.
Despite having similar designs, study results differed.
While the brain cells reached their maximum potential after roughly 10 minutes, the hydrogel took closer to 20 minutes.
“Over time, as the ball moves, the gel gathers a memory of all motion. And then the paddle moves to accommodate that ball within the simulated environment,” Strong explained.
“The ions move in a way that maps a memory of all motion over time, and this “memory” results in improved performance.”
It is easy to liken the gel to artificial intelligence systems, which can also “learn” over time despite being unconscious.
The researchers believe hydrogels represent a different kind of “intelligence” that could educate the development of simpler algorithms online.
The team plans to test the hydrogel’s “memory” by assigning different tasks.
“In our follow-up projects, we are thinking about how to extract the algorithm from the hydrogels that allows memory acquisition,” co-author William Holderbaum said.
Scientists are hesitant to say hydrogels can definitively “learn” without further research.
Rather, the study demonstrates the ability of non-living materials to use “memory” to update their understanding of the environment.
Corresponding author Yoshikatsu Hayashi even compared the gel’s behavior to neural patterns within the human body.
“Our paper addresses the question of whether simple artificial systems can compute closed loops similar to the feedback loops that allow our brains to control our bodies,” Hayashi said.
Hydrogel is a network of hydrophilic polymer chains, meaning they have a strong affinity for water.
The goo can absorb and retain large amounts of water or biological fluids without dissolving.
It’s typically soft, flexible, and able to mimic the properties of natural tissue.
Hydrogels can be found in everyday products like hair gels and contact lenses.
However, they’re also used in medicine, namely wound dressings and drug delivery systems.
The multi-use goo can promote in healing or be used as scaffolding in tissue engineering.
Their ability to swell and retain moisture makes the gel particularly useful when hydration is critical.
