Attentional blink is an interesting phenomenon that uses Rapid Serial Visual Presentation (RSVP). In RSVP a series of stimuli are presented quickly in squence all in the same place. In this experiment, you will be asked to locate two targets. They can be presented in either order and sometimes there is only one. What happens, usually, in this experiment is that if you detect the first target, sometimes you miss the second if it is close in time to the first. This is called the Attentional Blink. It seems that detecting and registering the first target makes it harder to detect the second target for a brief period of time.
In this experiment, you can mainipulate some of the parameters of the RSVP task and see how it impacts attentional blink.
You can adjust several parameters to design your own version of the experments. The settings are discuss below.
You can adjust several parameters to design your own version of the experments. The settings are discussed below.
Presentation Rate (ms): the at which the letters are presented in the RSVP.
Non-target color: set the non-targets to be either black or selected at random from a small set of colors. Red is one of the random colors.
Color of First Target is: choose if the first target is black or colored like the rest of the letters (Same) or Red.
Color of Second Target is: the same as the first target or the same as the rest of the letters in the list (black or colored).
Font Size: choose the font size of the letters.
Background Gray Level : the brightness of the background, in basic display units. This variable alters the contrast between the letters and the background.
Duration of Fixation (ms): how long the fixation mark is on (ms).
Reset Stimulus At the top of the settings is a Reset Stimulus button. Pressing this button restores the method settings to their default values.
Number of Levels of Separation (must be less than half total
number of items in list): this is the principle independent variable during the
experiment. How many separation levels. The separation levels start with 1 (or the two targets are
adjacent in the list) and counting up.
Percentage of Trials with Second Target: the percentage of trials where the second target is presented (there is always a first target).
Number of Trials/Separation: how many trials at each level of separation between the two targets.
Reset Method At the top of the settings page is a Reset Method button. Pressing this button restores the stimulus settings to their default values.
Change the settings below to alter the stimulus parameters in this experiment.
Change the settings below to alter the parameters of the experimental method.
Below, press the spacebar or the Open Experiment Window button on the screen to open the window where the experiment will run. When this screen opens, press the spacebar or click the "Start" button to begin the experiment. There are instructions above the "Start" button. Read them to know how to perform the experiment. Keep your eyes fixated on the red plus sign in the middle of the screen.
Your data will be presented on the results tab. The x-axis will have the separation. The y-axis will show the percent correct for each target. To download your trial-by-trial, press the Show Data link. To download the summary data press the Show Summary link. This data will be stored in a csv format readable by most spreadsheet and statistical programs.