If your partner seems to be ignoring you after a flash of nudity on the television screen, it might not be his or her fault. New research indicates that people shown erotic or gory images frequently fail to process what they see immediately afterwards.
Portions of the research exploring this effect by Vanderbilt University psychologist David Zald and Yale University researchers Steven Most, Marvin Chun and David Widders will be published in the August issue of Psychonomic Bulletin and Review.
"We observed that people fail to detect visual images that appeared one-fifth of a second after emotional images, whereas they can detect those images with little problem after neutral images," Zald, assistant professor of psychology and member of the Vanderbilt Kennedy Center for Research on Human Development, said.
Anyone who has ever slowed down to look at an accident as they are driving by--or has been stuck behind someone who has--is familiar with the "rubbernecking" effect. Even though we know we need to keep our eyes on the road, our emotions of concern, fear and curiosity cause us to stare out the window at the accident and slow to a crawl as we drive by.
Zald and his colleagues set out to determine if the rubbernecking effect carries over into more minute lapses of attention through two separate experiments.
In the first experiment, research subjects were shown hundreds of pictures that included a mix of disturbing images along with landscape or architectural photos. They were told to search the images for a particular target image. An irrelevant, emotionally negative or neutral picture preceded the target by two to eight items. The closer the negative pictures were to the target image, the more frequently the subject failed to spot the target. In a subsequent study, which has not yet been published, the researchers substituted erotic for negative images and found the same basic effect.
"We think that there is essentially a bottleneck for information processing and if a certain type of stimulus captures attention, it can basically jam up that bottleneck so subsequent information can't get through," Zald said. "It appears to happen involuntarily."
Previous studies have demonstrated that there are limits to how much information we can hold in our visual short-term memory and that we often miss visual images that pass right before our eyes if we are paying attention to something else. The new research indicates that we can also miss what we are searching for if we are shown an unexpected image that impacts us emotionally, a situation the researchers call "emotion-induced blindness."
This effect can explain some common human behaviors. "If you are simply driving down the road and you see something that is sexually explicit on a billboard, the odds are that it is going to capture your attention and for a fraction of a second afterwards, you are going to be less able to pay attention to the other information in your environment," Zald said. "So you might not see that car coming at you or the person crossing the street because your bottleneck has been jammed."