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In a surprising study, scientists found that these famously alien-like creatures respond just like humans and other mammals when exposed to this sensory illusion. <\/p>\n
Their brains, which are vastly different from ours, still make the same mistake. That suggests a deeper commonality in how ownership of bodies<\/a> is understood by living minds, regardless of how those minds are built.<\/p>\n What the rubber hand trick shows<\/p>\n The rubber hand illusion<\/a> was first demonstrated in the 1990s. It involves hiding a person\u2019s real hand behind a screen while a fake rubber hand is placed in full view.<\/p>\n When both hands, real and fake, are stroked simultaneously, the brain starts to link the sensations to the fake hand. <\/p>\n Eventually, the person begins to feel ownership of the rubber hand. Pinch the fake one, and the person flinches. Later studies showed that mice were also fooled by the same trick. <\/p>\n The illusion appeared to tap into a widespread brain function that integrates vision, touch, and body awareness into a unified sense of self. But these animals are mammals<\/a>, like us.<\/p>\n Their brains share much of our architecture. So scientists naturally asked: What about creatures with entirely different neural setups?<\/p>\n How the octopus brain sees its arms<\/p>\n Octopuses are unlike any other creature<\/a> on Earth. They have nine brains \u2013 one main brain and eight smaller ones, one in each arm. Their nervous systems are highly distributed.<\/p>\n An arm can even move independently after being severed. This structure makes their cognition incredibly difficult to compare to ours. Still, they\u2019re known for cleverness, problem-solving, and even mischief.<\/p>\n So when researchers at the University of the Ryukyus<\/a> in Okinawa, Japan, set out to test whether octopuses would fall for the rubber hand illusion, the scientific community took notice. <\/p>\n If octopuses could be fooled too, it would mean their brains also create a kind of body image, despite the alien wiring.<\/p>\n That would change how we understand intelligence and body awareness across the animal kingdom.<\/p>\n How the fake arm test fooled octopuses<\/p>\n Sumire Kawashima and Yuzuru Ikeda led the study. They worked with six captive, plain-body octopuses (Callistoctopus aspilosomatis<\/a>). <\/p>\n Each was placed in a tank with an opaque barrier that blocked its view of one arm. Above this hidden arm, a fake octopus arm made of soft gel was placed. The fake arm looked natural and matched the posture of the real one.<\/p>\n A researcher then stroked both arms, the real hidden one and the fake, visible one, at the same time using plastic calipers. <\/p>\n This synchronized stimulation mimicked the human rubber hand illusion<\/a>. After eight seconds, they pinched the fake arm with tweezers and observed how the octopus responded.<\/p>\n Octopus reaction to fake arm<\/p>\n The reactions were clear and strong. All six octopuses showed defense responses when the fake arm was pinched. <\/p>\n Some changed color, some pulled back their arms, and others tried to escape. These are all natural behaviors that octopuses use when they sense danger.<\/p>\n But when researchers removed the synchronized stroking, or when the fake arm did not match the posture of the real one, the illusion failed. No defense responses occurred. The octopus no longer saw the fake arm as part of it\u2019s own body.<\/p>\n This result was striking. The illusion worked only when the visual and tactile cues matched perfectly. <\/p>\n That means the octopus brain was combining multiple types of information to build a sense of its own body. In that moment, the fake arm became real.<\/p>\n What the scientists learned<\/p>\n For co-author Yuzuru Ikeda, the study offers a glimpse into both the power and limits of brain function. <\/p>\n \u201cThe illusion would suggest the ability of octopuses<\/a> to anticipate and predict, which is advantageous for survival,\u201d he said. <\/p>\n \u201cOn the other hand, this ability arises as a side effect of a mistake or conflict of processing in the brain and is also a flaw.\u201d<\/p>\n In other words, this illusion is a double-edged sword. The same brain function that helps predict and react to the world can also misfire. And yet, this mistake reveals how sophisticated the octopus\u2019s sense of self may be.<\/p>\n Sumire Kawashima believes the findings push octopuses into an even more important role in neuroscience. <\/p>\n \u201cOur findings suggest the octopus may be an important model for studying the evolution of the sense of body ownership,\u201d she said. <\/p>\n This places octopuses alongside mammals as useful subjects for understanding consciousness and cognition.<\/p>\n More insights on animal consciousness<\/p>\n Peter Godfrey-Smith, a philosopher of science at the University of Sydney<\/a>, has long studied octopus minds. He was surprised by the results.<\/p>\n \u201cIt suggests that octopuses have quite a rich body image,\u201d he said. \u201cI am struck by the fact that the \u2018posture incongruence\u2019 condition worked as it did: the octopuses did not see the rubber arm as their own in that case, despite the stroking.\u201d<\/p>\n His reaction highlights just how unexpected this discovery is. Even subtle mismatches between the real and fake octopus arm broke the illusion. <\/p>\n That level of precision points to a complex internal model of the body, something many did not expect to find in a species so different from ours.<\/p>\n This experiment offers more than just an odd glimpse into animal behavior. It challenges deep assumptions about how minds work. <\/p>\n If both humans and octopuses can be tricked into adopting a fake limb, then perhaps the roots of self-awareness are older and more widespread than we believed.<\/p>\n<\/p>\n The study is published in the journal Current\u00a0Biology<\/a>.<\/p>\n \u2014\u2013<\/p>\n Like what you read? Subscribe to our newsletter<\/a> for engaging articles, exclusive content, and the latest updates.\u00a0<\/p>\n Check us out on EarthSnap<\/a>, a free app brought to you by Eric Ralls<\/a> and Earth.com.<\/p>\n \u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"Imagine reaching for a cup and feeling as though your hand is moving, only to discover it\u2019s not…\n","protected":false},"author":2,"featured_media":20330,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[49,48,66,323],"class_list":{"0":"post-20329","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-wildlife","8":"tag-ca","9":"tag-canada","10":"tag-science","11":"tag-wildlife"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/20329","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=20329"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/20329\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/20330"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=20329"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=20329"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=20329"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}