University of Minnesota
William Iacono is well known for his work with the Minnesota Twin Family Study, a benchmark investigation of about 1,900 sibling pairs and their parents that began more than two decades ago.
Photo: Patrick O'Leary
An epic investigator
New Regents Professor William Iacono makes his mark with the help of twins
By Rick Moore
William Iacono is the first to admit that his research doesn’t yield daily “Aha!” discoveries. But that’s to be expected when you examine your research subjects over the course of decades as opposed to days. Still, Iacono’s body of work has made a lasting impression within and beyond the University community; he was named a Regents Professor, the highest faculty rank at the U.
Much of Iacono’s renown comes from his work with the Minnesota Twin Family Study (MTFS), a benchmark longitudinal investigation of about 1,900 sibling pairs and their parents begun in 1987.
The study traces the development of twins from adolescence through adulthood to understand the underpinnings of substance use and mental health problems; specifically, how genes and the environment interact along the way.
Study participants spend significant time in Iacono’s psychophysiology laboratory. All told, the twins are screened across more than 100 different measures of characteristics like personality, family interactions, and religious behavior, and the data collection is repeated over time and updated for age appropriateness.
“If you measure enough things and do a good job of it, the idea is you should be able to see how those things work together to influence the [mental health] outcomes you see,” Iacono says.
Among his findings are that a person who has one “externalizing disorder” or antisocial behavior is likely to have another one, and this co-occurrence of disorders is more heritable than a single disorder. The goal is to find and understand the underlying biological mechanisms.
“Hopefully, all that will come together in a way that will improve the mental health of people in this country,” he says.
Detection of deception
Iacono smiles when asked about his litany of titles—professor of psychology, of psychiatry, of neuroscience, and of law—and how he came to piece together so many disciplines.
“I think it’s kind of atypical, because most people are far more focused and it’s easier to explain how they get from one point to another,” he laughs.
Early in his career, Iacono became involved with a lie detector study as a way of attracting students to his lab. Soon he found himself in demand to help with legal casework involving polygraph testing.
“In the process of doing that I found out there are very few psychologists who are willing to venture into this field,” he says. “It ends up being very important because it has huge implications for the individual lives of the people who take these tests, and also public policy implications in terms of whether or not employees should have to undergo polygraph tests to keep their jobs. It also has implications for national security. “
At home in Minnesota
Iacono spent a few years early in his career at the University of British Columbia in Vancouver, and took part in some groundbreaking research there involving schizophrenia.
But he jumped at the chance to return to the University of Minnesota—a place he considers his intellectual home in a state that he cherishes for its outdoor splendor.
“There probably is no other place where I would fit in better or feel more at home,” he says. “There isn’t really any other clinical psychology program in the country that has a focus like that [on the etiology and biological basis of psychopathology]. And we’re ranked in the top few and have been for decades.”
Perhaps more so than any of his research findings, he’s proud of the more than 40 doctoral and post-doctoral students he’s advised over the years, many of whom are now collaborators who have carved out their own distinguished academic careers.
As for the research, “We don’t have ‘Oh, we found a cure for cancer’ days in psychology,” he grins. “But I think we’ve made great strides toward understanding the development of abnormal behavior.”