See First and Grab Later

By: Yovan P. Putra

Maybe you are one out of many people who use alarm clock to wake you up in the morning. When the alarm clock ringing, the sound of the alarm wake you up, your blurry vision recognize the clock followed by your hand reaching it and shut it down afterward.

This simple mechanism seems out of question for many of us. But actually this process involves two separate systems, recognition and guidance. Neuroscientists have been long aware about this, but they had not been able to observe both in action.

Recent study conducted by Lior Shmuelof and Ehud Zohary of Hebrew University in Jerusalem tried to seek deeper concerning this phenomenon. They have used functional Magnetic Resonance Imaging (fMRI) to see duality in action in human volunteers.

In their study, the subjects watched videos of hands entering the screen from one side
and grasping objects on the opposite side. "Most previous studies of the two visual systems, were of people who had had brain damage", said Shumuelof. Those suffering from amnesia could not recognize objects, whereas those with ataxia could identify objects but could not guide their hands to grab them. "Our study confirmed that there are two systems," Shmuelof says, "But it also found that this model is too simple. Some parietal brain regions, associated with planning to grasp objects, are also involved in observing actions taken by others (the hand on the screen) to grasp objects."

In the future, they both want to study to what function this dual activity serves

Science
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 
 • 

» More on Science