FAYETTEVILLE, Ark. — Presidential candidates usually pay close attention to image and to managing the public’s perception of who they are. Surprisingly, though, in televised debates seen by millions, they can often seem oblivious to the impression they make on viewers at home, sometimes grimacing or rolling their eyes in response to an opponent.

In a study of the third presidential debate between John Kerry and George Bush, communication professor Rob Wicks and graduate students from four disciplines at the University of Arkansas found that viewers perceived candidates differently based on which network they watched. The study will be published in the late summer/fall issue of American Behavioral Scientist.

The researchers found that differences in production techniques influenced the impression that candidates made on audience members. C-SPAN maintained a split-screen format in which both candidates were shown throughout the entire debate. PBS, by contrast, focused most heavily on the candidate speaking. The other networks studied - ABC, Fox News and CNN - opted for split screens, reaction shots, close-ups and other editing techniques.

In the past, networks shared a common feed with identical images. But in 2004, they were free to vary their presentation styles by selecting from many camera angles and shots. Wicks and his research team wondered what influence, if any, these production differences would have on audience members. The team conducted an experiment in which University of Arkansas students were assigned to groups and asked to evaluate the candidates on a number of attributes before and after the debate.

The results suggested that each group of young viewers perceived Kerry as warmer following the debate. However, the greatest increase was for the group viewing the C-SPAN split-screen format, while the smallest increase was for those who viewed it on PBS, which tended to focus primarily on the speaker.

The results also suggest that each group of viewers perceived President Bush as weaker following the debate. However, PBS viewers perceived Bush as strong prior to the debate but much weaker afterward. C-SPAN viewers, who considered Bush to be strong before the debate, rated him as only slightly weaker afterward. The C-SPAN presentation style also minimized the difference in height between the two candidates. Thus, the PBS group in which 68 percent of the participants identified themselves as Republicans reported the greatest decline in perceptions of strength for Bush.

“Production values definitely influence how people interpret events,” said Wicks, an associate professor of communication in the J. William Fulbright College of Arts and Sciences. “Quick editing as was used by ABC, CNN and Fox News drew cognitive attention away from what the candidates were saying, while the static focus on one candidate at a time enabled viewers to better hear and judge what the candidates were saying. The C-SPAN approach seemed to have the greatest potential for changing perceptions as viewers were able to watch facial and nonverbal reactions of each debater as he spoke.”

Wicks also studied the Gore and Bush Web sites in 2000, noting that the Bush site had images of him in suits that conveyed stature and capability, while the Gore site showed him in much more informal clothes, chatting with groups of people. The pattern continued in 2004, with Bush images generally presenting the president as a statesman.

“Reagan, Clinton and Kennedy broke through the screen and conveyed a sense of warmth. That ability to communicate through the camera is absolutely vital to winning. More people watch debates than conventions, and if a candidate can pick up just a few points after a debate, those could easily change the outcomes, as likely was the case during the debates between Richard Nixon and John Kennedy in 1960 or Al Gore and George W. Bush in 2000,” said Wicks.

Wicks suspects that in the future, candidates will be coached to avoid strong reactions, facial expressions or body language. He plans to conduct similar studies, with larger and more diverse cross-sections of voters. Wicks works with a consortium of more than 40 universities in the country in which researchers are studying presidential elections and ways to get more young voters involved in politics.