For this lab we will be exploring the Posner Task and what it tells us about visual attention. To begin click here and read the instructions on the page. Once you have read the instructions click on the link that says "Click here to run a demo of the Posner task." Once you've completed the demo, return to this page.
Now that you've completed the Posner Task demo ask yourself:
When is it harder to respond, after a valid (the x is followed by the go) or an invalid (the x is NOT followed by the go) cue?
When you have to shift attention from an invalid cue to where the target is, what steps are you taking?
Most participants find it harder to respond after an invalid cue than after a valid cue. This is because the "x" cue draws our attention to an invalid location and we must shift our visual attention to respond to the "go" in the correct location.
From researching tasks like these, Posner developed his theory of visual attention. According to Posner's theory there are three steps involved in shifting attention:
1. Disengage: Stop attending to what is currently being attended