Instagram chief Adam Mosseri on Friday said that a test of hiding "likes" at the image and photo sharing social network will spread to the US."Heads up! We've been testing making likes private on Instagram in a number of countries this year," Mosseri said in a tweet."We're expanding those tests to include a small portion of people in the US next week."Facebook in September confirmed it is dabbling with no longer making a public display of how many "likes" are racked up by posts.Such a change could ease pressure to win approval with images, videos or comments and, instead, get people to simply focus on what is in the posts.Facebook-owned Instagram earlier this year announced it was testing hiding like counts and video view tallies in more than a half-dozen countries, with account holders still able to see the numbers but masking amounts from others.Twitter has also experimented with hiding numbers of times tweets were "liked" or "retweeted," according to product lead Kayvon Beykpour.Twitter found that people engaged less with tweets when they couldn't see the counts."When you remove engagement indicators, people engage less," Beykpour said while briefing journalists at Twitter headquarters in San Francisco earlier this year.