Skip to main content

New model more accurately predicts choices in classic decision-making task

A new mathematical model that predicts which choices people will make in the Iowa Gambling Task, a task used for the past 25 years to study decision-making, outperforms previously developed models. Romain Ligneul of the Champalimaud Center for the Unknown in Portugal presents this research in PLOS Computational Biology.
The Iowa Gambling Task presents a subject with four virtual card decks, each containing a different mix of cards that can win or lose fake money. Without being told which decks are more valuable, the subject then picks cards from the decks as they please. Most healthy people gradually learn which decks are more valuable and choose to pick cards only from those decks.
Earlier studies have used Iowa Gambling Task data to build mathematical models that can predict people's card-picking choices. However, building such models is computationally challenging, and previously developed models do not account for the exploratory strategies people use in the task.
In reviewing previously collected data from 500 subjects, Ligneul found that healthy people tend to cycle through the four decks and pick one card from each, especially at the beginning of the task. He then incorporated this behavior, termed sequential exploration, into a new mathematical model that also accounts for the well-known reward-maximizing behaviors people exhibit in the task.
Ligneul found that his new model outperforms earlier models in predicting people's card-picking choices. He also found that sequential exploration behaviors seem to decline as subjects get older, perhaps because of neurological changes typically associated with aging.
"This study provides a mathematical method to disentangle our drive to explore the environment and our drive to exploit it," Ligneul says. "It appears that the balance of these two drives evolves with aging."
The new model and findings could help refine insights gleaned from the Iowa Gambling Task. It could also improve understanding of learning and decision-making disruptions that are associated with aging and various neuropsychiatric conditions, such as addiction, impulsive disorders, brain injury, and more.
Story Source:
Materials provided by PLOS. 
Note: Content may be edited.

Comments

Post a Comment

Popular posts from this blog

Major surgery associated with small, long term decline in brain functioning

Major surgery is associated with a small long-term decline in cognitive functioning -- equivalent, on average, to less than five months of natural brain ageing, finds a study in  The BMJ  today. But the odds of substantial cognitive decline also increase after surgery -- approximately doubling -- although the likelihood of this is much lower than after admission to hospital for a medical condition, the findings show. Cognitive decline is the gradual loss of brain functioning that occurs with ageing. It often starts decades before the conventional definition of old age and accelerates with ageing and the presence of an increasing number of underlying health conditions. Certain health issues, such as stroke, can lead to a large "step change" in cognitive decline, and there have been concerns that surgery might also do this, with some patients refusing beneficial surgical procedures as a result, say the researchers. Few previous studies have looked at the potential im...
Post a Comment
Read more

Dark matter may be older than the Big Bang

Dark matter, which researchers believe make up about 80% of the universe's mass, is one of the most elusive mysteries in modern physics. What exactly it is and how it came to be is a mystery, but a new Johns Hopkins University study now suggests that dark matter may have existed before the Big Bang. The study, published August 7 in  Physical Review Letters , presents a new idea of how dark matter was born and how to identify it with astronomical observations. "The study revealed a new connection between particle physics and astronomy. If dark matter consists of new particles that were born before the Big Bang, they affect the way galaxies are distributed in the sky in a unique way. This connection may be used to reveal their identity and make conclusions about the times before the Big Bang too," says Tommi Tenkanen, a postdoctoral fellow in Physics and Astronomy at the Johns Hopkins University and the study's author. While not much is known about its origins,...
Post a Comment
Read more

Scientists challenge notion of binary sexuality with naming of new plant species

A collaborative team of scientists from the US and Australia has named a new plant species from the remote Outback. Bucknell University biology postdoctoral fellow Angela McDonnell and professor Chris Martine led the description of the plant that had confounded field biologists for decades because of the unusual fluidity of its flower form. The discovery, published in the open access journal  PhytoKeys , offers a powerful example of the diversity of sexual forms found among plants. The new species of bush tomato discovered in remote Australia provides a compelling example of the fact that sexuality among Earth's living creatures is far more diverse -- and interesting -- than many people likely realize. Bucknell University postdoctoral fellow Angela McDonnell and biology professor Chris Martine led the study following an expedition last year to relocate populations of the new plant, which were first noted by Australian botanists during the 1970s. Herbarium specimens from th...
Post a Comment
Read more