Brainstorm or Green Needle? How the latest audio riddle tricks your brain

A new ear-teaser to rival the ‘Yanny v Laurel’ debate which divided work colleagues, friends and family around the globe has been viewed by millions online.

Many viewers have reported hearing either the words ‘Green Needle’ or ‘Brainstorm’ depending on which of the two words they are thinking of as they watch the clip.

A clip of the light-up toy with a robotic voice racked up more than four million views on Twitter in less than 24 hours and has been widely shared across various social media channels.

Brainstorm or Green Needle
Brainstorm or Green Needle? A new audio riddle similar to Yanny v Laurel has been watched by millions  Credit: YouTube / DosmRider

“You can hear the words Green Needle or Brainstorm based on which one you think about,” tweeted Mitchell Moffit.

The clip was taken from a 2014 video by YouTube vlogger DosmRider, a reviewer of collectable toys, who confirmed to the Press Association what the toy is actually programmed to say.

“The toy is supposed to say Brainstorm,” he explained. “It’s the character’s name in the show Ben 10 Alien Force and the name is used in all the merchandise and the show.

“I was pretty surprised given that I usually don’t see any toy reviews or anything like that getting this kind of attention - (it) just seems hilariously random to me.”

The clip was later shared by Reddit user squidjeep, who explained: “These videos do well on the internet because it’s really cool to see how people’s brains work.

“People can be given similar inputs yet interpret them in such different ways.”

How it works: ‘Your brain's best guess at reality’

Valerie Hazan, professor of speech sciences at University College London, told The Telegraph the riddle is not dissimilar from the Yanny-Laurel case, explaining “the signal is more ambiguous here, which may favour the more easy switching from one to the other”.

“The effect seems to work as follows: when you ‘think’ Green Needle you hear that word, but when you ‘think’ Brainstorm, you hear the other.

“Basically, you are priming your brain to expect acoustic patterns that match expected patterns for a particular word. When faced with an acoustic signal which is somewhat ambiguous because it is low-quality or noisy, your brain attempts a ‘best fit’ between what is heard and the expected word.

“If it expected patterns for Green Needle, then it will track the patterns in the signal which have more energy in higher frequencies as these are more consistent with some patterns in the sounds in Green Needle. If it expects Brainstorm, it will track the lower-frequency patterns which are more consistent with those you would find in a clearer production of Brainstorm.”  

Suzy J Styles, a psycholinguist who specialises in brain, language and intersensory perception at Nanyang Technological University, Singapore, believes the “brain is filling in the gaps to make sense of the signal”, just like in the Yanny v Laurel case.

“The brain has lots of experience with a voice saying one thing at a time,” she says. “When there are two possibilities, the brain has to pick which seems more likely.

“In this case, if you are thinking Green Needle, it makes the acoustic cues that match those sounds stronger, so that's what you hear. If you are thinking Brainstorm, then those cues are stronger, so you hear that instead.

“This is a great reminder that everything we think we experience via the senses is just our brain's best guess at reality!”

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