You’ve heard of the Iowa Test of Basic Skills. Now meet its strung-out cousin, the Iowa Gambling Task.
IGT, also called the Iowa Gambling Task Experiment, is considered the gold standard for measuring cognitive decision-making. Thirty years after its debut, scientists (along with pop-science writers, podcasters and YouTubers) still continue to discuss it. In fact, researchers from two universities in China just published a follow-up study exploring the role of forgetting in decision-making on June 4 in the Decision Neuroscience section of Frontiers in Psychology, an open-access academic journal known for its rigorous peer-review process. On March 18, a team from the University of South Florida resynthesized the original study and offered improvements, including considering the impact of emotion-processing on decision-making.
But what is the Iowa Gambling Task exactly? I’ll do my best to interpret the landmark psychological tool and its impact for my fellow lay-Iowans.
It all goes back to a 1994 study titled “Insensitivity to future consequences following damage to human prefrontal cortex.” (If that already sounds sorta confusing, you’re not alone.) Antoine Bechara and four fellow researchers, known collectively as “Bechara et al,” devised a mechanism to explain the “defect in real-life decision-making” exhibited by people with a particular type of brain damage. They wanted to simulate scenarios that, as in real life, have uncertain outcomes, rewards and punishments.
That’s where the “task” comes in. Simulating a casino game, participants repeatedly choose cards from four decks labeled A, B, C and D, each with different schedules of monetary “rewards” and “punishments.” The goal is to accumulate as much “money” as possible after 100 trials. What they’re not told upfront is that C and D are “risky” decks with larger immediate rewards but harsher penalties, resulting in a lower — or even negative — overall payout. The other two are “safe” decks, with smaller individual reward amounts but less significant penalty cards, yielding a higher payout over time.
It’s in their decisions about which cards to choose that the magic of the task lies. Through trial and error at different rates, patients develop their own strategies for accumulating wealth — or debt. Common variations include giving out real money, using a digital touch screen and even conducting the task on rats.
The outcome? Subjects with prefrontal cortex damage seemed to be “oblivious to the future consequences of their actions.” This was significant, as it offered the first possibility of detecting, measuring and investigating the causes of this “elusive impairment.” Since its inception, IGT has been used to study the impact of a wide variety of conditions on the brain’s decision-making strategies, including alcoholism, pathological gambling, schizophrenia, ADHD, mood disorders like depression, cocaine dependence and Parkinson’s Disease.
However, with the IGT, the journey is more important than the destination. It’s the special design of the experiment itself — the “task” — that endures in psychological research and practice, as well as Iowa history.
This article is from Little Village’s December 2025 Peak Iowa issue, a collection of stories drawn from Hawkeye State history, culture and legend. Browse dozens of Peak Iowa tales here.
