Featured Research

from universities, journals, and other organizations

Will it fall? Scientists show how the brain's estimate of Newton's laws affects perceived object stability

Date:
April 29, 2011
Source:
Max Planck Institute for Biological Cybernetics
Summary:
Newton's laws of motion predict that an object will fall when its centre-of-mass lies beyond its base of support. But how does your brain know whether the tower will fall or not? Scientists in Germany recently reported that although the physical laws governing object stability are reasonably well represented by the brain, you are a better judge of how objects fall when you are upright than when you lay on your side.

A vase set at its critical angle where it is equally likely to right itself or fall off of the table.
Credit: © Martin Breidt, Roland Fleming, Manish Singh; MPI for Biological Cybernetics, Tuëbingen

Newton's laws of motion predict that an object will fall when its centre-of-mass lies beyond its base of support. But how does your brain know whether the tower will fall or not?

Scientists from the Max Planck Institute for Biological Cybernetics in Tübingen, Germany recently reported in the journal PLoS ONE that although the physical laws governing object stability are reasonably well represented by the brain, you are a better judge of how objects fall when you are upright than when you lay on your side.

"The force of gravity is not sensed directly," says Michael Barnett-Cowan, a Canadian postdoctoral neuroscientist and Project Leader for motion perception at the Max Planck Institute. "It is the indirect effects of gravity that are detected."

In the mid 19th century, Hermann Aubert tilted to one side and observed a vertical line as being tilted towards him. "Since Aubert we now know that the brain combines visual and vestibular information to determine gravity's direction relative to an internal representation of our body's orientation," Barnett-Cowan explains. "We wondered whether objects are perceived as stable relative to this biased perceived direction of gravity rather than gravity's true direction."

Equipping observers with laptops, testing them upright and on their sides, and comparing the participants' judgment of object stability and vertical line estimates, Barnett-Cowan and colleagues found evidence that our perception of the likelihood that an object will fall is relative to this biased perceived direction of gravity rather than gravity's true direction.

"We might expect the brain to depend primarily on visual heuristics and assumptions about an object when assessing whether it will fall or not," says Roland Fleming, now an assistant professor of psychology at the University of Giessen. "Surprisingly, however, we find that observers' judgments of object stability are biased towards the tilt of the body."

These findings have important implications for existing theories of how humans perceive the physical stability of objects. "Since the work of Jean Piaget it has been known that children and adults have difficulty in solving problems involving the physical laws which govern equilibrium, but in everyday life we seem to be quite good at estimating object stability," says Manish Singh, associate professor of psychology at Rutgers University. "Our results suggest that solving such problems may depend on integrating multisensory information."

"This is another fine example suggesting that in order for the brain to accurately represent objects in the world, it combines information from multiple sensory organs that individually do not provide an accurate representation of the physical world," adds Heinrich Bülthoff, Director of the Max Planck Institute for Biological Cybernetics.

We spend most of our time engaging in the world with an upright posture. "Here visual, vestibular and body sense cues are aligned and the brain can make use of this redundant information to maintain optimal perception and action, particularly when information from one sense is poor or lost," says Barnett-Cowan, who plans to assess perceived object stability in microgravity environments and in patients such as those with Parkinson's disease and muscular dystrophy.

So how should one look at the leaning tower of Pisa differently to make it appear more stable? "Pisa's tower may appear more stable than it is if you lay in the same direction of its lean," points out Barnett-Cowan. "Lay in the opposite direction, and it may appear even more likely to fall."


Story Source:

The above story is based on materials provided by Max Planck Institute for Biological Cybernetics. Note: Materials may be edited for content and length.


Journal Reference:

  1. Michael Barnett-Cowan, Roland W. Fleming, Manish Singh, Heinrich H. Bülthoff. Perceived Object Stability Depends on Multisensory Estimates of Gravity. PLoS ONE, 2011; 6 (4): e19289 DOI: 10.1371/journal.pone.0019289

Cite This Page:

Max Planck Institute for Biological Cybernetics. "Will it fall? Scientists show how the brain's estimate of Newton's laws affects perceived object stability." ScienceDaily. ScienceDaily, 29 April 2011. <www.sciencedaily.com/releases/2011/04/110428070237.htm>.
Max Planck Institute for Biological Cybernetics. (2011, April 29). Will it fall? Scientists show how the brain's estimate of Newton's laws affects perceived object stability. ScienceDaily. Retrieved April 19, 2014 from www.sciencedaily.com/releases/2011/04/110428070237.htm
Max Planck Institute for Biological Cybernetics. "Will it fall? Scientists show how the brain's estimate of Newton's laws affects perceived object stability." ScienceDaily. www.sciencedaily.com/releases/2011/04/110428070237.htm (accessed April 19, 2014).

Share This



More Mind & Brain News

Saturday, April 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Study On Artists' Brain Shows They're 'Structurally Unique'

Study On Artists' Brain Shows They're 'Structurally Unique'

Newsy (Apr. 17, 2014) — The brains of artists aren't really left-brain or right-brain, but rather have extra neural matter in visual and motor control areas. Video provided by Newsy
Powered by NewsLook.com
Is Apathy A Sign Of A Shrinking Brain?

Is Apathy A Sign Of A Shrinking Brain?

Newsy (Apr. 17, 2014) — A recent study links apathetic feelings to a smaller brain. Researchers say the results indicate a need for apathy screening for at-risk seniors. Video provided by Newsy
Powered by NewsLook.com
Are School Dress Codes Too Strict?

Are School Dress Codes Too Strict?

AP (Apr. 16, 2014) — Pushing the limits on style and self-expression is a rite of passage for teens and even younger kids. How far should schools go with their dress codes? The courts have sided with schools in an era when school safety is paramount. (April 16) Video provided by AP
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) — A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins