Our brain thinks our shadow is part of our body
If it looks at though something is about to touch our shadow, our brain activity shows that the brain thinks a part of our body is about to be touched.
Volunteers, distracted with flashing lights, were tested for their reaction speed and accuracy.
Scientists found similarities in brain activity (errors) when a light was flashed on the person hand or the shadow of his/her hand.
Our brains develop an internal map, this helps the brain define exactly where the body is (and this helps it navigate around the world outside).
According to researchers, our own shadows are part of that map. The researchers were from the Royal Holloway College (London) and Unversita degli Studi di Trento (Rovereto, Italy).
Volunteers sat down in front of a white table. Their shadows were cost onto the surface of the white table.
Researchers asked the volunteer to distinguish between toughes on the thumb and forefinger of the hand, and the number of errors (and overall reaction time) were recorded.
The scientists tested volunteers' reaction speed and accuracy while distracting them with flashing lights.
What amazed the scientists was that they found similar errors when lights flashed either next to the volunteer's hand and the shadow of his/her hand.
When a flashing light appears near the volunteer's hand, his/her errors rise and reaction time slows down. When a flashing light appears near his/her hand's shadow, the same level of error and slowness of reaction time takes place.
Scientists tried flashes in the same place but without the shadow. This failed to produce the same effect. Even flashes next to a disguised hand shadow (forming a different shape from the owners shadow) did not produce the same effect.
The study was published in the journal Nature Neuroscience.
Creierul nostru crede umbra noastrã face parte din corpul nostru - Our brain thinks our shadow is part of our body - articole medicale engleza - startsanatate