According to American researchers, systematic changes in brain activity help the eyes find objects, even when an individual does not know where they have been kept.
The researchers from the University of California have discovered that more neurons are called into action to enable the eyes to find a particular object than has previously been documented.
In the course of study, the non-invasive technique of functional magnetic resonance imaging (fMRI) was used to see systematic changes in the brain activity as the participants observed a certain object in motion, no matter where it appeared in their visual field.
"This increased activity in the brain is what helps you find objects you are looking for, even when you don't know exactly where the objects are," said John Serences, UC Irvine cognitive scientist.
During the study, the researchers presented participants with a computer display of objects moving in different directions. All the participants were directed to pay attention to objects moving in a particular direction—for example, the object moving to the left.
Upon using fMRI to indirectly measure neural activity, the researchers found that the patterns of brain activity change when people pay attention to objects moving in different directions.
It was also noted that paying attention to one direction of motion made the brain more responsive to other objects moving in that direction, no matter where the other objects appear in their visual field—a phenomenon that has not previously been documented.
The findings, published in the journal Neuron, may enhance scientists' understanding of problems like Attention Deficit Hyperactivity Disorder, and explain how healthy people's brains create awareness of their surroundings.
"By gaining a more thorough understanding of how a healthy human brain functions, we will be better equipped in the future to recognize, diagnose and treat abnormalities within the brain," Serences says.