Facebook, Twitter are designed to act like 'behavioural cocaine'
Silicon Valley insiders tell the BBC about social media's deliberate addictive qualities.

Silicon Valley insiders told the BBC that social media sites are designed to be addictive.
Social media companies work hard to get us addicted to their services, Silicon Valley insiders have reportedly revealed.
Features such as infinite scroll and Likes keep people looking at their phones for longer than necessary and feed on their insecurities, they told the BBC's Panorama for a documentary set to air Tuesday.
Aza Raskin, formerly of Mozilla and Jawbone, created infinite scroll in 2006, making it possible to swipe down through content endlessly without having to click.
"If you don't give your brain time to catch up with your impulses, you just keep scrolling," he said.
Raskin says he didn't intend to get people addicted, but feels guilty about the impact of his innovation, he told the BBC. However, now it's just one of several features social media platforms use to get users hooked.
"It's as if they're taking behavioural cocaine and just sprinkling it all over your interface and that's the thing that keeps you like coming back and back and back", he said.
Social media apps are designed to get inside our heads.
"Behind every screen on your phone, there are generally like literally a thousand engineers that have worked on this thing to try to make it maximally addicting."
Leah Pearlman, who co-created Facebook's Like button with Justin Rosenstein, admitted to the BBC that even she got addicted to the social media service as she sought Likes on her posts.
"When I need validation -- I go to check Facebook," she said.
"I'm feeling lonely, 'Let me check my phone.' I'm feeling insecure, 'Let me check my phone.'"
Last year, Rosenstein noted that the Like button had led to a rise in clickbait.
"I think it's also caused the distribution of things that, even if people Like them, aren't necessarily time well spent," he said.
Facebook has also made it easy for websites to add its Like button to their pages.
The company denied that its service is deliberately designed to be addictive.
"The allegations that have arisen during BBC Panorama's production process are inaccurate. Facebook and Instagram were designed to bring people closer to their friends, family, and the things that they care about," a spokesperson for Facebook and Instagram said.
"This could be connecting with loved ones that live far away, or joining a community of people that share your interests or support the causes that matter most to you. This purpose sits at the centre of every design decision we make and at no stage does wanting something to be addictive factor into that process."
Earlier this year, Facebook CEO Mark Zuckerberg made changes to its News Feed to increase "time well spent" on its site, but the person in charge of that feature later admitted that the company is still "trying to figure out" exactly what that means.
In June, it was rumored that the tech giant was testing a tool called "Your Time on Facebook" designed to help users manage time spent on the site.
Twitter declined to add comment, while Snapchat didn't immediately respond to a request for comment.
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