Thaindian News

Washington, April 28 (ANI): You can best determine the actual position of the Leaning Tower of Pisa when you are upright, according to a new study.

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 Tubingen, Germany, have found 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. It is the indirect effects of gravity that are detected,” said Michael Barnett-Cowan, a Canadian postdoctoral neuroscientist and project leader for motion perception at the Max Planck Institute.

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,” said Barnett-Cowan.

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’ team 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.

“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,” said Heinrich Bulthoff, Director of the Max Planck Institute for Biological Cybernetics.

“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,” he said.

These findings have important implications for existing theories of how humans perceive the physical stability of objects.

The study was published in the journal PLoS ONE.