Washington (AFP) - When politicians talk in a friendly way that focuses on helping others, US public approval ratings rise, according to a study out Monday.
But when elected leaders in the US House of Representatives stop stressing cooperation, public approval declines, according to research that spanned nearly two decades and 124 million words spoken during debates in the halls of Congress.
"The individual words whose use most strongly predicted public approval were as follows: gentle, involve, educate, contribute, concerned, give, tolerate, trust and cooperate," said the study by Canadian and German researchers in the Proceedings of the National Academy of Sciences, a peer-reviewed US journal.
Researchers used software to analyze 123,927,807 words spoken in the US House of Representatives between 1996 and 2014.
The computer checked for linguistic markers of what is known as "prosocial language," meaning words that indicate a concern with the collective good.
Then, the researchers compared levels of prosocial language within each month of Congress with its approval ratings by the American public.
They discovered "a striking match," said the study.
"Public approval peaked in the aftermath of the (2001) September 11 attacks, declined over the next seven years, rose slightly in the wake of the 2008 financial crisis, and then declined again," it added.
"Prosocial language followed a nearly identical trajectory."
- Huge drop in approval -
In 2002, public approval of Congress reached 84 percent. But in 2013, public approval reached an all-time low of 10 percent, according to background information in the article.
A relatively small drop in cooperative language -- 20 percent from 2002 to 2014 -- was associated with a much larger, nearly 75 percent decrease in public approval.
Researchers said the effects of language remained apparent even when they controlled for the impact of major world and national events.
"Warm, prosocial language still predicted public approval when removing the effects of societal and global factors (e.g. the September 11 attacks) and Congressional efficacy (e.g. passing bills), suggesting that prosocial language has an independent, direct effect on public approval," according to the study.
Researchers said language caused the approval rating to change because they could observe a time lag between changes in the types of words used and the varying approval ratings -- typically about six to seven months later.
In other words, "what Congress says today best predicts their approval ratings 29 weeks into the future," the study said.
Researchers also looked at the impact of friendly words on the media and found that the more politicians talked nice, the more positive coverage they earned from news editorials.
"Our results suggested that prosocial language in Congress predicted positive media coverage. And positive media coverage predicted public approval," the researchers said.
Researchers at the University of Winnipeg, University of Vancouver, University of Waterloo, University of British Columbia and University of Manitoba authored the study, along with colleagues from the Mannheim Centre for European Social Research at the University of Mannheim in Germany.