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In 1901, David Hänig published a paper

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that forever changed [br]our understanding of taste.

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His research led to what we know [br]today as the taste map:

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an illustration that divides the tongue [br]into four separate areas.

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According to this map,

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receptors at the tip of our tongues[br]capture sweetness,

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bitterness [br]is detected at the tongue’s base,

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and along the sides, receptors capture [br]salty and sour sensations.

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Since its invention, the taste map [br]has been published

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in textbooks and newspapers.

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The only problem with this map, [br]is that it’s wrong.

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In fact, it’s not even [br]an accurate representation

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of what Hänig originally discovered.

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The tongue map is a common misconception—

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something widely believed [br]but largely incorrect.

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So where do misconceptions [br]like this come from,

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and what makes a fake fact [br]so easy to believe?

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It’s true that the tongue map’s [br]journey begins with David Hänig.

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As part of his dissertation [br]at Leipzig University,

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Hänig analyzed taste sensitivities across [br]the tongue for the four basic flavors.

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Using sucrose for sweet, [br]quinine sulfate for bitter,

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hydrochloric acid for sour, [br]and salt for salty,

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Hänig applied these stimuli to compare [br]differences in taste thresholds

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across a subject’s tongue.

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He hoped to better understand [br]the physiological mechanisms

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that affected these four flavors,

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and his data suggested that sensitivity [br]for each taste

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did in fact vary across the tongue.

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The maximum sensation for sweet [br]was located at the tongue’s tip;

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bitter flavors were strongest at the back;[br]salt was strongest in this area,

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and sour at the middle [br]of the tongue’s sides.

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But Hänig was careful [br]to note that every sensation

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could also be tasted across the tongue,

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and that the areas he identified offered [br]very small variations in intensity.

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Like so many misconceptions,

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the tongue map represents a distortion [br]of its original source,

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however the nature of that distortion [br]can vary.

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Some misconceptions [br]are comprised of disinformation—

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false information intentionally designed [br]to mislead people.

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But many misconceptions, [br]including the tongue map,

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center on misinformation—[br]false or misleading information

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that results from unintentional [br]inaccuracy.

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Misinformation is most often shaped [br]by mistakes and human error,

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but the specific mistakes [br]that lead to a misconception

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can be surprisingly varied.

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In the case of the tongue map,

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Hänig’s dissertation was written [br]in German,

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meaning the paper could only be [br]understood by readers fluent in German

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and well versed in Hanig’s [br]small corner of academia.

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This kicked off a game of telephone [br]that re-shaped Häing’s research

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every time it was shared [br]with outside parties.

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Less than a decade after his dissertation,

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newspapers were falsely insisting [br]that experiments

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could prove sweetness was imperceptible [br]on the back of the tongue.

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The second culprit [br]behind the tongue map’s spread

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were the images [br]that Hänig’s work inspired.

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In 1912, a rough version of the map [br]appeared in a newspaper article

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that cautiously described [br]some of the mysteries

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behind taste and smell research.

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Featuring clear labels across the tongue,[br]the article’s illustration

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simplified Hänig’s more-complicated [br]original diagrams.

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Variations of this approachable image [br]became repeatedly cited,

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often without credit or nuanced [br]consideration for Hänig’s work.

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Eventually this image spread [br]to textbooks and classrooms

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as a purported truth [br]of how we experience taste.

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But perhaps the factor that most [br]contributed to this misconception

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was its narrative simplicity.

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In many ways,

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the map complements our desire for clear [br]stories about the world around us—

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a quality not always present [br]in the sometimes-messy fields of science.

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For example,

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even the number of tastes we have is more [br]complicated than Hänig’s work suggests.

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Umami— also known as savory— [br]is now considered the fifth basic taste,

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and many still debate [br]the existence of tastes

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like fatty, alkaline, metallic, [br]and water-like.

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Once we hear a good story,

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it can be difficult to change [br]how we see that information,

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even in the face of new evidence.

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So, next time you see a convenient chart [br]or read a surprising anecdote,

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try to maintain a healthy skepticism—

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because misconceptions [br]can leave a bitter taste

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on every part of your tongue.