Saturday, January 27, 2007
Psychophysiology and Media: Intro to my mad science
In my last post I mentioned a hope that research myself and other colleagues do might improve media content. One specific area I research concerns the design of effective health communication campaign messages. I thought a brief review of an experiment conducted in this area would make for a useful review of psychophysiology, one of the primary methods I use to study how the human brain processes media messages. The fundamental assumption of psychophysisology as a research method is that how physiological systems in the human body (i.e. Heart) respond while a person is engaged in processing information in their environment can be used to indicate psychological processes (i.e. attention).
The experiment I am going to tell you about is an experiement where we were interested in finding out how fear appeal and the presence of disgust evoking scenes in anti-tobacco use messages affect intensity of negative emotional response and attention allocated to encoding the message in memory. Fear appeal is a message strategy that focuses on trying to persuade targeted individuals by presenting a threat to their well being. Many anti-tobacco messages have also adopted a strategy of including disgusting scenes such as images of diseased body organs (i.e. a smoker's lung) in an attempt to intensify negative emotional responses to tobacco use.
Our experimental design was a 2 (Fear appeal: high vs. low) X 2 (Disgust image: present or not present). High fear appeal ads in our study focused on "death" as the threat component of the message. Participants in the experiment were undergraduate college students. Our physiological indicator of intensity of negative emotional response was corrugator muscle activity. The corrugator muscle is located along your eyebrow and it has been shown to be involved in expressing a negative emotional response. Our physiological indicator of attention was heart rate. Heart rate has been shown to decelerate as a person pays more attention to encoding media content like television into memory.
As you can see in the included charts, corrugator muscle activity across viewing our anti-tobacco ads was strongest for low fear appeal ads that included disgusting images. These ads also resulted in the strongest and most consistent pattern of cardiac deceleration (slowest heart rate). This pattern of results suggests that low fear, high disgust eliciting anti-tobacco television ads are probably the most effective at evoking negative emotion towards tobacco use and capturing attention. This suggests that the most effective message strategy for anti-tobacco ads targeting young adults is to position tobacco use as a dirty, disgusting behavior and present the visual images in the ad to back that claim up!
This is just a little example of the media research done in the PRIME Lab. I'll present other studies as they come in. I hope this has been interesting to read. I'd enjoy engaging in any discussion about health messages you might like to raise. On a side note, since I am an advertising Professor it is fun for me to enjoy the "Superbowl"...of advertising. I'll comment after the big game about whose ad I think was worth the 2.5 million dollars advertisers are paying to be on the superbowl this year!