Our memories, while they serve us well, can also lie.
Because of the way the brain stores memory information in fragments, parts of the memory get scrambled when reconstructing it, so-called False memories.
For the first time, evidence of false memories has been found in cuttlefish, a species entirely different to humans.
It’s a clue that helps us understand those in power better. Strange Intelligence Not only squid,Sepia officinalis) but also by closely related cephalopods such as octopuses and, to a lesser extent, squids.
“Our results suggest that cuttlefish form visual but not olfactory false memories.” Write a team “These memory errors may be the first indication of the existence of a restructuring process in cephalopod memory,” said the team, led by neuroethologist Lisa Poncet of the University of Caen-Normandy in France.
In past experiments, cuttlefish have shown evidence of remarkable intelligence, including passing cognitive tests designed for human children that assess their ability to postpone cravings. They can also be trained to recognise shapes and associate them with specific rewards.
And in relation to today’s news, they’ve demonstrated the ability to recall incredibly vivid, specific, detailed memories: These strange marine animals can remember what they ate, where they ate it, and when they ate it. Episodic memory.
Ponce and his colleagues wanted to know how those memories are recalled—whether they emerge from the brain in one smooth burst, or whether, like humans, the squid brain has to reconstruct pieces of memories from where they’re encoded and stored.
Because false memories can be created when very similar memories are mixed together, the researchers designed their experiment accordingly: They exposed the squid to successively similar experiences involving containers of snacks.
One of the tubes contained crab meat, which the squid eats, even though it is not their favorite food. The second tube contained shrimp, which the squid loves. The third tube was empty. Each tube was marked with an identifying pattern.
The experiment had three steps.
In step one, the squid was shown the three tubes so that they could see their unique patterns and contents without touching them.
In step two, one of a variety of scenarios was used. In one case, a shrimp tube and an empty tube were presented together – both were empty but turned around to hide that fact from the squid. In another scenario it was the same, but the two tubes were only tagged with the shrimp scent. In the third scenario, the empty shrimp tube stood alone.
In the third phase, the squids were given an empty tube with a crab-shaped one inside, and each tube was turned upside down to hide its contents. The aim was to see whether the squids would remember accurately which tube contained food, or whether a false memory would lead them to choose the empty tube, mistakenly thinking it contained shrimp.
The results weren’t simple, but they suggested that misleading visual information had planted a false memory: When the step-two scenario only featured an empty tube, the squid ducked into the crab’s container about 80 percent of the time.
However, when shown both shrimp and an empty tube in the second part, the squids were only able to find the crab by chance, as if they had mistaken the empty tube for the one containing shrimp.
Curiously, when they added odor to the tank in the second phase, the crabs almost always chose the crab tube again, which seemed to have an effect in blocking the formation of false memories.The researchers speculate that there are several reasons why the smell of the prey might help prevent the formation of false memories.
The team also acknowledged that they could not rule out simpler explanations, such as familiarity with the empty tubes causing the confusion.
The research is still in its very early stages, so all we know for now is that the way cuttlefish recall memories may be very similar to how humans do.
There are several other clues that suggest squid memory may have similarities to human memory. 2012 Study It has been discovered that cuttlefish undergo REM sleep. REM sleep is Memory stabilization.
And actually, that’s pretty fascinating: Cephalopods diverged from vertebrates around 550 million years ago, and their evolution since then has been very different from almost every other life on Earth, meaning that these fascinating creatures have a lot to teach us about the evolution of cognition and intelligence.
And there’s something else that seems to suggest that squid intelligence is deeper than we knew and deserves further investigation.
“What surprised us was that individuals appear to vary in their susceptibility to forming false memories.” Cristel José Alves says of the University of Caen Normandy.
“Some people are unaffected by exposure to misleading events, while others form false memories. This phenomenon is common in our species, and this susceptibility varies both inter- and intra-individual.”
Surely the squid wouldn’t mind if better tasting shrimp were offered.
This study iScience.
