A new report by the Nielsen Co. confirms a trend among viewers that has been gaining momentum for some time: the use of a second screen while watching TV.

And the second screen of choice, increasingly, is Twitter, the social network that’s just six years old and limits messages to 140 characters.

“Twitter has become the second screen experience for television," said Nielsen social media Vice President Deirdre Bannon.

The report “illustrates the explosive growth in people who watch TV while connected to social media on smartphones and tablets,” reports David Bauder of the Associated Press.

Nielsen found that one in three people using Twitter in June sent messages at some point about TV shows, the story notes. "And that was before the Olympics, which was probably the first big event to illustrate the extent of second screen usage," Bauder writes.

The study also found almost one-third of people between 18 and 24 used social networking sites while in the bathroom.

At least once per day, about 41% of tablet owners and 38% of smartphone owners used their devices while watching TV, the report notes.

"There are big and interesting implications," Bannon said. "I think both television networks and advertisers are onto it."

The piece notes: “The social media can provide networks with real-time feedback on what they are doing. The performance of moderators at presidential debates this fall was watched more closely than perhaps ever before, because people were instantly taking [to] Twitter to provide their own critiques.”

But the story also notes a contrast in current trends: “The increase in people watching television and commenting about it online would seem to run counter to another big trend this fall: more people recording programs and watching them at a later hour. Those contrary trends both increase the value of live event programming like awards shows or sporting events.”