VISUAL ATTENTION EXPERIMENT

    A                             B                      C                           D

In this experiment, you will make responses to items on a computer screen.

What you will see on the screen.

Look at the figure above. Each picture (A, B, etc.) represents an event displayed on the computer screen.

A.You will see a small dash in the center of the screen.Your job is to direct your eyes to the dash.There is a small video camera, to ensure that you do not move your eyes around the screen.If you move your eyes, you will be reminded not to.Of course, it's OK to blink or rest between trials.

B.You will see a flash of light (a cue) to either the right, left, top, or bottom.That is your signal that a target will appear at that location very soon.Your job is to move your attention (not your eyes) to that location.Remember, if you move your eyes you will be reminded not to do so.

C.The screen will be blank for a very brief fraction of a second.

D.On most trials (90%), a target will appear (very briefly) at the cued location. On 10% of trials, the target will appear somewhere else. The target will have an odd leg pointing either up, down, left, or right.Try to identify the direction that the leg is pointing.It will not be easy to see the target.A plus sign ("+") will appear at the other location.

Your response. Your job is to push the arrow on the keyboard that matches the direction of the leg on the target. If the leg of the target was pointing up, you will push the arrow on the keyboard, etc.The important thing is to be as fast as possible, without making too many errors.It’s not important to be 100% accurate.

To make it easier to respond without looking at the keyboard, most people rest three fingers and a thumb on the arrow keys.The experimenter will show you how to do this.

You will get to practice this until it is easy! Then you will do 8 blocks of 90 trials, which takes about 40 minutes.