I See and I Remember

A Study on How Eyewitness Memory Works

Spotting missing children by recognizing their faces from posters in supermarkets or picking a possible criminal from a line-up can be enormously difficult tasks for most people — as law enforcement and parents know. Researchers are studying what they term “prospective person memory,” which is the ability to remember to do something in the future.
      Their goal: to find approaches that will improve people’s ability to detect and recognize faces.

We are using prospective person memory whenever we see a picture of a missing child or perhaps of a suspected criminal and then later believe we have seen that person and contact authorities for help.
       Fulbright researchers James Lampinen and Jack Arnal, along with Jason Hicks of Louisiana State University, are investigating the factors that influence eyewitness testimony.

To test how this memory works, the research team conducted several experiments.

In one, they stopped a sample of people who were just leaving a grocery store at random times on Thursday, Friday, and Saturday afternoons. The variables of the time of day or the day of the week didn’t affect the outcome: few customers had even looked at the posters of missing children on the walls. In fact, the ability to recognize a person from memory didn’t differ much from chance in this scenario.

When asked, however, nearly 70% of the customers said they did not even look at the posters, but an equal number rated the problem of finding missing children as “extremely” important.

“Customers at grocery stores are typically very busy, eager to get home or to continue on to other errands,” says Lampinen, associate professor of psychology. “But many of them were very concerned and even downright apologetic about the fact they did not stop to look at the posters.”

Store posters on walls have become so commonplace they have lost their novelty, but an alternative can be taken from the lesson of point-of-purchase advertising: place a canister with the picture of the missing person directly on the checkout counter, where people will stop long enough to take notice of a photograph.

Overall, the rate of identification — whether it be missing persons or fugitives — is always higher when people are shown on national television.

Lampinen and fellow researchers also tested how well a relatively recent technique works — age progressed photographs. About one-third of the pictures of children featured in fliers are age-progressed photos, which involves taking an outdated photograph of a child and using computer software to produce an image that estimates the child’s current appearance.

For this test, a forensic artist was given photographs of volunteers taken at age 7 and then asked to create a depiction of the volunteers as they might appear at age 12. Researchers compared the age progressed images with actual pictures of the volunteers at 12.

“Age progression by itself didn’t help, and that’s problematic because many people put faith in this method,” says Lampinen.

People need to keep in mind, though, that both age progressed photographs and outdated photographs are more effective than chance alone and provide some help in finding missing children.

“We’re not saying that age progression doesn’t work. Rather we are trying to determine how to make all of these techniques as effective as possible.”

Recently Lampinen and his students have been working with Let’s Bring Them Home to address the problem of finding missing children. Organizations such as Let’s Bring Them Home (http://www.lbth.org/) as well as the National Center for Missing & Exploited Children (http://www.missingkids.com/) can certainly help, along with gaining local, and if possible, national publicity.

A closely related area of interest is in how well the general public is able to correctly identify wanted fugitives in typical real world situations.

The researchers tested this ability by asking student volunteers from four different introductory psychology classes to watch a mock news broadcast show that simulated a search for two bank robbers. The reporter never came out and said that the two people shown in the report were wanted by authorities, but just told his audience that if they contacted their instructor, they would win a part of a $100 prize.

Two days later, the “wanted” parties in the video held a cookie sale for the psychology club on the second floor of Memorial Hall, where the psychology classrooms and faculty rooms are located. Since classrooms for the general psychology courses are all on the third floor, students had to pass by the sale when their classes were over.

The result: less than 4% of the students present for both the cookie sale and the mock news broadcast made a correct identification.

Then, in one more test to see how focused their attention was, the researchers sent students in half of the classes an e-mail before the cookie sale with a coupon promising two for the price of one. This additional
enticement increased identification again, but only slightly. In none of the studies did the identification rate exceed 7%.

Researchers know that some variables influencing the accuracy of eyewitnesses to crime are not under the control of the legal system: sometimes witnesses are more accurate when identifying members of their own race, or they can be influenced by how much stress they experienced during the event they witnessed, be it a bank robbery or a purse snatching.

Lampinen says what is unique about this approach to studying memory is the way both experimental and field research are being conducted to uncover what principles underlie how people both form and carry out their good intentions.

The work lies at the intersection of a growing interest in prospective memory and the more compelling everyday aspects of memory — which, for most of us, means just doing what we intended to do that day.

 

 

back to main page >>