Attentional shift

There are two types of attentional shifts that are helpful in obtaining visual information. These two shifts are covert and overt. Each is used for different amounts of visual information obtained in the environment observed.

Covert attentional shifts are those in which visual stimuli are processed without fovea shifts or eye movement. Per second approximately 20 to 30 objects can be visually processed through covert shifts. This type of shift helps to obtain basic spatial layout and knowledge of how various stimuli relate to each other.

Overt attentional shifts are when the direction of the fovea is moved with the change of attention. Three to four objects can be processed within a second when overt shifts are utilized. Although slower that cover attentional shifts, overt helps obtain more detail of select stimuli. In essence it helps with focusing attention on specific stimuli.