When a momentous television event takes place like, say, (spoiler alert) Cousin Matthew’s tragic end on Downton Abbey or Seth MacFarlane’s boob song at the Oscars, you can be sure the Twittersphere lights up with reaction.

And apparently, now there is evidence of a direct correlation between Twitter chatter and TV ratings, according to a recent study by Nielsen and SocialGuide.

The study found that premiere TV episodes which saw an 8.5 percent increase in related Twitter activity also saw a 1 percent increase in TV program ratings among 18 to 34 year olds.

Among 35 to 49 year olds, a 14 percent increase in Twitter volume was needed to boost ratings 1 percent--an indication that there's a stronger relationship between Twitter and television ratings for younger audiences.

The study also found that later in a TV program's season, the relationship between Twitter and its ratings strengthened for both groups. In the middle of the season, a Twitter volume increase of 4.2 percent among 18 to 34 year olds and 8.4 percent among 35 to 49 year olds corresponded with a 1 percent increase in ratings for both groups.

Twitter also drove more of the variance in ratings than did advertising spending, according to the study. 

A previous internal Nielsen study on the 2011 TV season suggested that the relationship between Twitter and television ratings reached its peak during a show’s finale.