--- title: Black Dots: Why You Can't See All At Once description: The visual trick is a photo of intersecting grey lines against a white background, with 12 black dots on the image where the grey lines meet canonical: https://time.com/4487295/optical-illusion-black-dots/ author: Mahita Gajanan article:opinion: false article:content_tier: free article:published_time: 2016-09-12T13:35:51.000Z article:modified_time: 2026-04-13T07:36:24.820Z og:title: Why Your Brain Won't Let You Look at These Black Dots All at Once og:description: How many dots can you see? og:url: https://time.com/4487295/optical-illusion-black-dots/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt888bc8b88f1cc8fa/6988a587656a3f3e2ebcd0b8/twitter-black-dots.jpg?branch=production&width=2400&quality=75&auto=webp&crop=16:9 og:image:width: 1200 og:image:height: 675 og:image:alt: twitter-black-dots og:type: article twitter:card: summary_large_image twitter:title: Why Your Brain Won't Let You Look at These Black Dots All at Once twitter:description: How many dots can you see? twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt888bc8b88f1cc8fa/6988a587656a3f3e2ebcd0b8/twitter-black-dots.jpg?branch=production&width=2400&quality=75&auto=webp&crop=16:9 ---  # Why Your Brain Won't Let You Look at These Black Dots All at Once by [Mahita Gajanan](https://time.com/author/mahita-gajanan/) ## Mahita Gajanan Gajanan is an editor at TIME. Sep 12, 2016 1:35 PM UTC  Twitter by [Mahita Gajanan](https://time.com/author/mahita-gajanan/) ## Mahita Gajanan Gajanan is an editor at TIME. Sep 12, 2016 1:35 PM UTC A new optical illusion is here to [break the internet](http://time.com/3725528/dress-explainer-white-gold-blue-black-science/), or at least our minds. The latest visual trick making the rounds is an image of intersecting grey lines against a white background, with 12 black dots on the nodes where the grey lines meet. All 12 dots are really on the image, but most people are unable to see them all at the same time, making the dots seem like they appear and disappear with every blink. This occurs because the eye’s stimulated light receptors can sometimes influence the ones next to them, creating illusions. > [](https://twitter.com/wkerslake/status/775105333333204992) In this particular image, [tweeted by game developer Will Kerslake](https://twitter.com/wkerslake/status/775105333333204992) on Sunday, the brain can see some black dots but [guesses when it fills in the peripheral vision](http://www.theverge.com/2016/9/12/12885574/optical-illusion-12-black-dots). Because mostly grey lines appear in the periphery, the black dots don’t appear. The image is a variation on the [Hermann grid illusion](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.294.6770&rep=rep1&type=pdf), a diagram of black squares separated by white lines. Dark patches appear where the white lines intersect, but only in a person’s periphery. How many dots can you see at once? ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4487295/optical-illusion-black-dots/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4487295/optical-illusion-black-dots/"},"headline":"Why Your Brain Won't Let You Look at These Black Dots All at Once","datePublished":"2016-09-12T13:35:51.000Z","dateModified":"2026-04-13T07:36:24.820Z","description":"How many dots can you see?","url":"https://time.com/4487295/optical-illusion-black-dots/","keywords":["Newsfeed","viral"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt888bc8b88f1cc8fa/6988a587656a3f3e2ebcd0b8/twitter-black-dots.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Mahita Gajanan","jobTitle":"Gajanan is an editor at TIME.","url":"https://time.com/author/mahita-gajanan/"}],"articleSection":"","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt888bc8b88f1cc8fa/6988a587656a3f3e2ebcd0b8/twitter-black-dots.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"twitter-black-dots","caption":"","creditText":"Twitter","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/tag/time-section-newsfeed/","name":"Newsfeed"}},{"@type":"ListItem","position":2,"item":{"@id":"https://time.com/4487295/optical-illusion-black-dots/","name":"Why Your Brain Won't Let You Look at These Black Dots All at Once"}}]}] ```