COOK: Does your work have any application in lie detection?
PENNEBAKER: It does. Several labs, including ours, have now conducted studies to evaluate the prospect of building a linguistic lie detector. The preliminary findings are promising. In controlled studies, we can catch lying about 67% of the time where 50% is chance. Humans, reading the same transcripts, only catch lying 53% of the time. This is actually quite impressive unless you are a person in the judicial system. If you are waiting for a language-based system to catch real world lying at rates of 90 or 95 percent of the time, it won’t happen in your lifetime. It’s simply too complicated.
COOK: What are you looking into now? Where do you see the field going in the future?
PENNEBAKER: One of the most fascinating effects I’ve seen in quite awhile is that we can predict people’s college performance reasonably well by simply analyzing their college admissions essays. Across four years, we analyzed the admissions essays of 25,000 students and then tracked their grade point averages (GPAs). Higher GPAs were associated with admission essays that used high rates of nouns and low rates of verbs and pronouns. The effects were surprisingly strong and lasted across all years of college, no matter what the students’ major.
To me, the use of nouns -- especially concrete nouns -- reflects people’s attempts to categorize and name objects, events, and ideas in their worlds. The use of verbs and pronouns typically occur when people tell stories. Universities clearly reward categorizers rather than story tellers. If true, can we train young students to categorize more? Alternatively, are we relying too much on categorization strategies in American education?
I think one advantage I have had in my career is that I’ve got a short attention span. If something new and exciting bubbles up in our data, I will likely drop what I’m doing and try to understand it. It’s a wonderful time to be alive.
Are you a scientist who specializes in neuroscience, cognitive science, or psychology? And have you read a recent peer-reviewed paper that you would like to write about? Please send suggestions to Mind Matters editor Gareth Cook, a Pulitzer prize-winning journalist at the Boston Globe. He can be reached at garethideas AT gmail.com or Twitter @garethideas.