Aviation securityBehavioral observation as a security method questioned

Published 7 October 2011

Agencies in charge of airport security believed they had a good idea: why not add behavioral observation of passengers as an added layer of security on top of the various screening and scanning machines already placed at airports around the United States; experts question the method’s efficacy

Behavioral observation officer with airline passengers // Source: 680news.com

Agencies in charge of airport security believed they had a good idea: why not add behavioral observation of passengers as an added layer of security on top of the various screening and scanning machines already placed at airports around the United States.

The assumption behind behavioral observation is that individuals intent on doing harm inadvertently reveal their intentions in their facial expressions.

Some experts question that assumption, and say that millions of dollars may be being misspent on threat-detection methods that rely on facial expression recognition.

The National Post reports that in the October issue of the journal Current Directions in Psychological Science, Lisa Feldman Barrett rebuts the notion of there being six to ten biologically basic emotions that are encoded — and easily interpreted — on people’s faces.

Barrett, a distinguished professor at Northeastern University in Boston, instead presents evidence that context “dramatically” shapes people’s ability to read emotion in a face, and that deciphering facial expressions on their own is at once misguided and a risk to public safety.

“When we’re trying to read the intentions of other people — which is the basis of deception detection — the face is not necessarily the key,” says Barrett. “The idea that people can read emotional expressions, or microexpressions, in the absence of context doesn’t seem to be borne out by the literature.”

For example, when participants were asked to match like facial expressions (say, a scowl with a scowl) with no other cues, accuracy was just 42 percent; but when people were asked to match faces to specific emotion words (such as anger or sadness), their accuracy rose to 83.4 percent.

“What to a researcher can seem like an inert part of an experiment — giving people emotion words to match to a face — turns out to be the active ingredient,” says Barrett. “If you strip away context from experimental procedures, you see accuracy in emotion perception drop precipitously.”