Freaky ‘’Rubber Hand’ Illusion’ Works on Octopuses, Too

The bizarre “hand hand” illusion also works on the octopus

By Gennaro Tommanding Edited by Sarah Lewin Frasier

In the classic illusion of the “hand of the rubber”, the illusion, a participant is deceived to experience a false arm on the table in front of them like theirs: their brain “feels” the tickling of a feather or other stimuli which they see applied to the false arms. (The real arm is behind a score.) So far, only some mammals, such as humans and mice, were known to be sensitive to this illusion. But a recent study in Current biology shows that octopus brains can be deceived in the same way, adding another ride to what we know about the inner life of these creatures.

Scientists first placed a octopus in a water tank where it could relax on a soft substrate similar to the seabed. Then they inserted a score that covered one of the arms of the octopus and left a visible false instead. “It was important to make the rubber arm look like the real arm of the octopus because in human experience, the illusion does not occur if the false hand is shaped differently from the real human hand,” explains the main author of the Sumire Kawashima study, biologist at the University of Ryukyus in Japan.

On the support of scientific journalism

If you appreciate this article, plan to support our award -winning journalism by subscription. By buying a subscription, you help to ensure the future of striking stories about discoveries and ideas that shape our world today.

Then the researchers simultaneously caressed the real and the false arms with tweezers. After about eight seconds, they continued to stimulate only the false arms. The six octopuses that respected the researchers’ test conditions reacted to stimulating the false arms with defensive responses such as escape maneuvers or body color changes. But when the experimenters have tried different approaches such as caressing only the false arms or caressing their arms asynchronously, the octopus “were not surprised at all,” said the co-author of the Yuzuru Ikeda study, also a biologist at the University of Ryukyus.

The results suggest that the octopuses fall into the same illusion as humans – and can therefore have a feeling of bodily property like us, according to the researchers. But the sensitivity of the octopuses at illusion is an interesting result in itself because such a perception has been considered one of the “very advanced capacities” of humanity, says Ikeda.

“I had never seen anything like this before,” said Kristin Andrews, a philosopher at York University in Toronto, who studies animal spirits. She says that the study seems to provide evidence that octopus is “aware” or aware of their body, although “we cannot assume that octopus have the same intuitive belief in a separation between a central self and the body that humans seem to have. [They] could see the world in a very different way. »»

It’s time to defend science

If you enjoyed this article, I would like to ask for your support. American scientist has been a defender of science and industry for 180 years, and at the moment can be the most critical moment of this two -centuries story.

I was a American scientist The subscriber since the age of 12, and that helped shape my way of looking at the world. Sciam Educates me and always delights me, and inspires a feeling of fear for our vast and magnificent universe. I hope that does this for you too.

If you subscribe to American scientistYou help make sure that our cover is focused on significant research and discoveries; that we have the resources necessary to report the decisions that threaten laboratories in the United States; And that we support the budding scientists who work at a time when the value of science itself does not become often again.

In return, you get essential news, Captivating podcasts, brilliant infographics, Maybe not miss newsletters, videos to watch, Difficult games and the best writings and reports in the scientific world. You can even Give someone a subscription.

There has never been more time for us to get up and show why science counts. I hope you will support us in this mission.