Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study Shows How the Brain Forms Habits

26.10.2010
Most people have habits that guide them through daily life — for example, their path to work in the morning, or their bedtime routine.

The brain patterns that drive this behavior are not well-understood, but a new study from MIT’s McGovern Institute for Brain Research shows that habit formation appears to be an innate ability that is fine-tuned by experience — specifically, the costs and rewards of certain choices.

Neuroscientists led by Institute Professor Ann Graybiel found that untrained monkeys performing a simple visual scanning task gradually developed efficient patterns that allowed them to minimize the time it took to receive their reward.

The task was designed to mimic natural scenarios — a nearly infinite number of choices for the monkeys to make and an unpredictable reward structure. “We wanted to create an environment that would be similar to the world we walk around in every day — an environment where there are lots of choices the animal can make,” says Theresa Desrochers, an MIT graduate student and lead author of a paper describing the work in the Proceedings of the National Academy of Sciences the week of Oct. 25.

The findings not only help reveal how the brain forms habits, but also could shed light on neurological disorders where amplified habit-formation results in highly repetitive behavior, such as Tourette’s syndrome, obsessive-compulsive disorder and schizophrenia, says Graybiel.

Graybiel and Desrochers took an unusual approach to their study. In most behavioral studies of monkeys, the researchers first train the animals to perform a task, then begin experiments. In this case, Graybiel and Desrochers wanted to see if the monkeys could learn a simple visual free-scanning task with no training at all.

The researchers measured the monkeys’ eye movements and brain activity as they looked at a grid of either four or nine dots. In each trial, after a period of time when the monkey just looked around, a different dot was randomly chosen to be “baited,” meaning that the monkey succeeded in the trial when its gaze landed on that dot. After a successful trial ended, the monkey received a food reward.

While the task itself is simple, it is capable of generating a rich variety of behavior, due to the number of choices available to the animals. The monkeys performed such trials about 1,000 times a day, and over several months, they developed ways to look at all of the different dots in sequences that were more and more cost-effective — meaning that they reached the target dot faster.

The changes were gradual: The animals would use one pattern for five to 10 days, then shift to a slightly different pattern. When looking at the entire mass of data, the researchers couldn’t tell what was driving these changes. However, a trial-by-trial analysis revealed that very small variations in the scanning patterns could reduce the overall time to receive the reward, which would then reinforce that behavior and lead the monkey to adopt the new pattern.

“The upshot was that tiny little changes in cost — how far they moved the eyes — seemed to be driving these shifts until they did it as optimally as they could, despite the fact that they had never been instructed,” says Graybiel.

This suggests that primates have an “inborn tendency to maximize reward and minimize cost,” says Graybiel. She and Desrochers believe the same kind of phenomenon, known as reinforcement learning, may also guide human habit formation.

“When you drive to work, it’s never going to take exactly the same amount of time. You might try one different street to avoid a stoplight, or some other subtle variation. At some point, you may completely shift,” says Desrochers.

Desrochers and Graybiel plan to design studies that will test whether humans show the same kind of habit-forming behavior in an eye-scanning task similar to the one the monkeys learned. They also hope to discover which parts of the brain control habit formation. They believe that the basal ganglia, which play a role in learning, and the prefrontal cortex, which is involved in planning, are likely candidates.

Funding: National Eye Institute Grant, the Office of Naval Research Grant, National Defense Science and Engineering Graduate Fellowship, Friends of the McGovern Fellowship and a Sloan Research Fellowship

Source: “Optimal habits can develop spontaneously through sensitivity to local cost” by, Theresa M. Desrochers, Dezhe Z. Jin, Noah D. Goodman, and Ann M. Graybiel. Proceedings of the National Academy of Sciences, 25 October, 2010.

Julie Pryor | Newswise Science News
Further information:
http://www.mit.edu

More articles from Studies and Analyses:

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

nachricht A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists spin artificial silk from whey protein

X-ray study throws light on key process for production

A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Breaking the optical bandwidth record of stable pulsed lasers

24.01.2017 | Physics and Astronomy

Choreographing the microRNA-target dance

24.01.2017 | Life Sciences

Spanish scientists create a 3-D bioprinter to print human skin

24.01.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>