New York University Skip to Content Skip to Search Skip to Navigation Skip to Sub Navigation

Humans & Monkeys of One Mind When It Comes to Changing It, NYU & Stanford Researchers Find

June 19, 2014
363

Covert changes of mind can be discovered by tracking neural activity when subjects make decisions, researchers from New York University and Stanford University have found. Their results, which appear in the journal Current Biology, offer new insights into how we make decisions and point to innovative ways to study this process in the future.

“The methods used in this study allowed us to see the idiosyncratic nature of decision making that was inaccessible before,” explains Roozbeh Kiani, an assistant professor in NYU’s Center for Neural Science and the study’s lead author.

The study’s other authors included Christopher Cueva and John Reppas of Stanford’s Department of Neurobiology and William Newsome, who holds appointments at the university’s Department of Neurobiology and at the Howard Hughes Medical Institute at Stanford’s School of Medicine.

Previous work on the decision-making process—a plan of action based on evidence, prior knowledge, and payoff—has been methodologically limited. In earlier studies, scientists analyzed one neuron at a time, then averaged these results across neurons to develop an understanding of this activity. However, such a measurement offers only snapshots of neurological behavior and misses the fine-scale dynamics that lead up to a decision.

In the Current Biology study, the researchers examined many neurons at once, giving them a more detailed understanding of decision making.

“Now we can look at the nuances of this dynamic and track changes over a specified period,” explains Kiani. “Looking at one neuron at a time is ‘noisy’: results vary from trial to trial so you cannot get a clear picture of this complex activity. By recording multiple neurons at the same time, you can take out this noise and get a more robust picture of the underlying dynamics.”

The researchers studied macaque monkeys, running them through a series of tasks while monitoring the animals’ neuronal workings.

In the experiment, the monkeys viewed a patch of randomly moving dots on a computer screen. Following the stimulus, monkeys received a “Go” signal to report the motion direction by making an eye movement. The scientists sought to predict the monkeys’ choices purely based on the recorded neural responses before the Go signal. Their model achieved highly accurate predictions.

The same model was then used to study potential dynamics of the monkeys’ decision at different times before the Go signal. The scientists confirmed these predictions by stopping the decision-making process at arbitrary times and comparing the model predictions with the monkeys’ actual choices.

Surprisingly, the monkeys’ decisions were not always stable. Occasionally, they vacillated from one choice to another, indicating covert changes of mind during decision-making. These changes of mind closely matched the properties of human changes of mind, which were uncovered in a 2009 study. They were more frequent in uncertain conditions, more likely to correct an initial mistake, and more likely to happen earlier during a decision.

The research was supported by the Howard Hughes Medical Institute, the Air Force Research Laboratory (FA9550-07-1-0537), a Berry Postdoctoral Fellowship, and a Sloan Research Fellowship.
 

This Press Release is in the following Topics:
NYUToday-feature, Arts and Science, Research, Faculty

Type: Press Release

Press Contact: James Devitt | (212) 998-6808

Humans & Monkeys of One Mind When It Comes to Changing It

Covert changes of mind can be discovered by tracking neural activity when subjects make decisions, researchers from NYU and Stanford University have found. Their results offer new insights into how we make decisions and point to innovative ways to study this process in the future. ©Purestock/Thinkstock


Search News



NYU In the News

Paying It Backward: NYU Alum Funds Scholarships

The Wall Street Journal profiled Trustee Evan Chesler on why he decided to chair the Momentum fund-raising campaign.

A Nobel Prize Party: Cheese, Bubbles, and a Boson

The New Yorker talked to Professor Kyle Cranmer and graduate student Sven Kreiss about NYU’s role in the discovery of the Higgs boson, which resulted in a Nobel prize for the scientists who predicted its existence.

The World as They Knew It

The New York Times reviewed the exhibit at the Institute for the Study of the Ancient World on how ancient Greeks and Romans mapped the known and unknown areas of their world.

Elite Institutions: Far More Diverse Than They Were 20 Years Ago

NYU made stronger gains over the last 20 years in increasing diversity than any other major research university, according to the Chronicle of Higher Education.

Program Seeks to Nurture ‘Data Science Culture’
at Universities

The New York Times reported on the multi-million collaboration among NYU and two other universities to harness the potential of Big Data, including an interview with Professor Yann LeCun, director of NYU’s Center for Data Science.

NYU Footer