Nav: Home

NYU study explains why mistakes slow us down, but not necessarily for the better

January 21, 2016

Taking more time to make decisions after a mistake arises from a mixture of adaptive neural mechanisms that improve the accuracy and maladaptive mechanisms that reduce it, neuroscientists at New York University have found. Their study, which addresses a long-standing debate on the value of deliberation after errors in decision-making, also potentially offer insights into afflictions that impair judgments, such as Alzheimer's Disease and Attention Deficit Hyperactivity Disorder (ADHD).

"Our research reveals that a combination of changes in the brain slow us down after mistakes," explains Braden Purcell, an NYU post-doctoral fellow and a co-author of the study, which appears in the journal Neuron. "One gathers more information for the decision to prevent repeating the same mistake again. A second change reduces the quality of evidence we obtain, which decreases the likelihood we will make an accurate choice."

"In the end, these two processes cancel each other out, meaning that the deliberative approach we take to avoid repeating a mistake neither enhances nor diminishes the likelihood we'll repeat it," adds Roozbeh Kiani, an assistant professor in NYU's Center for Neural Science and the study's other co-author.

It's been long established that humans often slow down after mistakes, a phenomenon called post-error slowing--or PES. Less clear, however, are the neurological processes that occur under PES.

The NYU researchers sought to address this question through a series of experiments involving monkeys and humans. Both watched a field of noisy moving dots on a computer screen and reported their decision about the net direction of motion with their gaze. The experimenters controlled the difficulty of each decision with the proportion of dots that moved together in a single direction--for instance, a large proportion of dots moving to the right provided very strong evidence for a rightward choice, but a small proportion provided only weak evidence.

Humans and monkeys showed strikingly similar behavior. After errors, both slowed down the decision-making process, but the pattern of slowing depended on the difficulty of the decision. Slowing was maximum for more difficult decisions, suggesting longer accumulation of information. However, the overall accuracy of their choices did not change, indicating the quality of accumulated sensory information was lower.

Brain activity observed from the monkeys while they performed the task shed light on what was happening in the brain. Specifically, the researchers analyzed neural responses from a region of parietal cortex involved in accumulating information in their task. During decision making, these neurons represent evidence accumulation by increasing their activity over time at a rate that depends on the quality of evidence. Specifically, stronger motion leads to faster ramping and weaker motion leads to slower ramping.

After mistakes, the exact same motion stimulus produced neural activity that ramped more slowly--consistent with impaired quality of sensory evidence. Critically, however, the neurons showed significant increase in how much evidence was accumulated before a decision, preventing a reduction in the overall accuracy.

"Patients with ADHD or schizophrenia often do not slow down after errors and this has been interpreted as an impaired ability to monitor one's own behavior," explains Purcell. "Our results suggest that this absence of slowing may reflect much more fundamental changes in the underlying decision making brain networks. By better understanding the neural mechanisms at work after we make a mistake, we can begin to see how these afflictions impair this process."
-end-
The research was supported by a Sloan Research Fellowship, a NARSAD Young Investigator Grant, a Whitehall Research Grant, a National Institutes of Heath training grant (T32EY007136), and a post-doctoral fellowship from the Simons Collaboration on the Global Brain.

New York University

Related Brain Articles:

Transplanting human nerve cells into a mouse brain reveals how they wire into brain circuits
A team of researchers led by Pierre Vanderhaeghen and Vincent Bonin (VIB-KU Leuven, Université libre de Bruxelles and NERF) showed how human nerve cells can develop at their own pace, and form highly precise connections with the surrounding mouse brain cells.
Brain scans reveal how the human brain compensates when one hemisphere is removed
Researchers studying six adults who had one of their brain hemispheres removed during childhood to reduce epileptic seizures found that the remaining half of the brain formed unusually strong connections between different functional brain networks, which potentially help the body to function as if the brain were intact.
Alcohol byproduct contributes to brain chemistry changes in specific brain regions
Study of mouse models provides clear implications for new targets to treat alcohol use disorder and fetal alcohol syndrome.
Scientists predict the areas of the brain to stimulate transitions between different brain states
Using a computer model of the brain, Gustavo Deco, director of the Center for Brain and Cognition, and Josephine Cruzat, a member of his team, together with a group of international collaborators, have developed an innovative method published in Proceedings of the National Academy of Sciences on Sept.
BRAIN Initiative tool may transform how scientists study brain structure and function
Researchers have developed a high-tech support system that can keep a large mammalian brain from rapidly decomposing in the hours after death, enabling study of certain molecular and cellular functions.
Wiring diagram of the brain provides a clearer picture of brain scan data
In a study published today in the journal BRAIN, neuroscientists led by Michael D.
Blue Brain Project releases first-ever digital 3D brain cell atlas
The Blue Brain Cell Atlas is like ''going from hand-drawn maps to Google Earth'' -- providing previously unavailable information on major cell types, numbers and positions in all 737 brain regions.
Landmark study reveals no benefit to costly and risky brain cooling after brain injury
A landmark study, led by Monash University researchers, has definitively found that the practice of cooling the body and brain in patients who have recently received a severe traumatic brain injury, has no impact on the patient's long-term outcome.
Brain cells called astrocytes have unexpected role in brain 'plasticity'
Researchers from the Salk Institute have shown that astrocytes -- long-overlooked supportive cells in the brain -- help to enable the brain's plasticity, a new role for astrocytes that was not previously known.
Largest brain study of 62,454 scans identifies drivers of brain aging
In the largest known brain imaging study, scientists from Amen Clinics (Costa Mesa, CA), Google, John's Hopkins University, University of California, Los Angeles and the University of California, San Francisco evaluated 62,454 brain SPECT (single photon emission computed tomography) scans of more than 30,000 individuals from 9 months old to 105 years of age to investigate factors that accelerate brain aging.
More Brain News and Brain Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Clint Smith
The killing of George Floyd by a police officer has sparked massive protests nationwide. This hour, writer and scholar Clint Smith reflects on this moment, through conversation, letters, and poetry.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.