Hanover College
Psychology  .
Department
 
.

 
 

Instructions for the Stroop Experiment

 

This experiment will allow you two generate your own Stroop experiment with anywhere from 1 to 4 conditions.  When you click on the link below, you will be presented with the experiment setup screen where you can set up the conditions for your experiment.  If you do not change any conditions, your experiment will have the two classic conditions of the Stroop experiment: Congruent words, where the color word and the color of the word match, and incongruent words, where color word and the color of the word are different.  In both conditions, your task is to respond to the color of the word.

The table below describes all of the variables that you can set and what the default settings are for the standard experiment.  The default setting is in bold and parentheses at the end of the list of settings.

Variable Settings (Default)
Number of Conditions to Test 1,2,3, or 4. (2)
Conditions Below is a list of conditions that you can use in the experiment.
  • Congruent Words (color and word same)
  • Incongruent Words (color and word different)
  • XXXX Colored (string of X's colored)
  • Word White
  • Congruent Reversed (color and word same but word backward)
  • Incongruent Reversed (color and word different but word backward)
  • Beginning Congruent (first two letters of the color word then x's in congruent color)
  • Beginning Incongruent (first two letters of the color word then x's in an incongruent color)
  • End Congruent (two x's then last letters of word in congruent color)
  • End Incongruent (two x's then last letters of word in incongruent color)
  • Middle Random Congruent (first and last letter in correct position, the middle in random order in congruent color)
  • Middle Random Incongruent (same as above but in an incongruent color)
  • End Random Congruent (first letter in correct position, rest of letters in random position, in congruent color)
  • End Random Incongruent (same as above but in an incongruent color)
  • Beginning Random Congruent (last letter incorrect position, the rest in random position, in congruent color)
  • Beginning Random Incongruent (same as above but in an incongruent color)

(Congruent Words and Incongruent Words) (Some conditions are incompatible with other conditions because of limitation on responding to different conditions.  If you pick a condition that has a response conflict, you will be informed of this situation, and your choice will not be allowed.)

Colors to Use Click on the check boxes to have the colors and the corresponding words used in your experiment.

Red, Green, Blue, Yellow, Orange, and Purple
(Red, Green, Blue, Yellow)

Respond to What? Whether the participant is to respond to the color or the word.  (Set automatically and not available in conditions XXXColored, for partial words, and when the words are not colored).

Respond to Color, Respond to Word
(Respond to Color)

Number of Words in Condition The number of words that will be displayed, from 20 to 200.
(25)
Location of the word Center, Left, or Right.  If the words are not centered, there is a fixation mark shown and the words are oriented vertically.
(Center)
Distance from Center If the words are not centered, this is the distance of the word from the center measured as a proportion of the distance from the center to the edge of the screen. (0nly visible when location is other than center).
(0)

After you have finished making your settings, press the Done button at the bottom of the screen. 

The Stroop experiment screen will then be presented.  In the middle the screen, brief instructions will be presented.  You will be told what condition you will be running next and whether to respond to the color or the word.  Note that the order of the conditions will be randomly determined by the experiment.

Press the button at the top of the page or the space bar to begin the experiment.  First a fixation mark in the middle of the screen will be presented.  It will be removed if the words are presented in the center.  When the word or string of X'x is presented, respond as indicated in the instructions.  You can do this three ways:

  1. press the relevant button at the bottom of the screen.
  2. press the following keys: r for red, g for green, b for blue, y for yellow, o for orange, or p for purple.
  3. press the following keys: a for red, f for green, j for blue, ; for yellow, x for orange, or m for purple.

The stimuli are randomly selected but words are never repeated twice in a row.

At the end of the experiment, your results will be presented, both average reaction time and your accuracy.  You can also get your trial by trial results.  To submit your data to Online Psychology Laboratory, press the "Submit Data" button at the bottom of the screen.  Closing your results window(s) will take you back to the setup window so you can run another experiment.

Click here to start the experiment.