Not since The Dress has the internet ripped itself in half over a sensory puzzle like this.
In case you haven’t been online in the last 24 hours, that puzzle is a two-syllable sound clip that appeared on Reddit and has since gone viral.
When you hit the Play button, a computer-generated voice says the word, looping it over and over. The word is “Laurel.”
Or maybe “Yanny” (pronounced “yeah-knee”).
Some people hear “Laurel” and will go to their graves insisting that there’s no other possibility. Others hear “Yanny” and nothing will budge their opinions. In-office polls put the perceptions right around 50-50.
I heard “Laurel” on my laptop. My wife, at her office on her phone, texted that she heard “Yanny.” We were each dumbfounded.
When she got home, though, listening on a different device in a different room, we both heard “Yanny.” But when I played a pitch-shifted (higher or lower) version, it was indisputably “Laurel” for both of us.
In desperation, I sought an expert opinion. Dr. Bradford May, an auditory scientist at Johns Hopkins University, puts it like this:
“Computer synthesis programs can produce unnatural sounds that fall on the boundaries between the two sounds. The listener will place these chimeric sounds into one category or the other depending on the best match. Because humans have differences in their auditory function and category boundaries, some will hear ‘Yanny,’ while others will hear ‘Laurel.’ This relates to the difficulty some Japanese speakers have with R vs. L sounds, which are not distinguished in the Japanese language.
“Humans learn language by learning to attend to meaningful sound patterns, and by learning to ignore specific acoustic features of those sounds that are not important. So, a child, an adult female, and an adult male will produce very different acoustic patterns when they say ‘Yanny,’ but you will hear ‘Yanny’ because you are attending to the underlying meaningful pattern, not the talker-specific acoustic features. This is called categorical perception.
“You will never confuse ‘Yanny’ and ‘Laurel’ when spoken by actual talkers, because they can only produce natural sounds that fall within the distinct parameter spaces of the two sounds.”
In other words, if the Yanny/Laurel puzzle weren’t computer-generated, it couldn’t exist. The sound we’re hearing is a combo that merges the two words; we hear different things because our hearing is different, and because our brains categorize differently.
(If you can hear only one word or another, this will help to open your mind: The Times made a slider that lets you adjust the frequencies so that one word or the other jumps out.)
Bottom line: As with The Dress, someone has stumbled upon an absolutely incredible razor’s-edge bit of hybrid sensory input. It doesn’t matter if you hear “Yanny” or “Laurel”; the good news is that you’re right.
David Pogue, tech columnist for Yahoo Finance, welcomes non-toxic comments in the Comments below. On the web, he’s davidpogue.com. On Twitter, he’s @pogue. On email, he’s firstname.lastname@example.org. You can sign up to get his stuff by email, here.
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