Stroop Effect
There are many things in life that we do automatically because of repeated practice after the initial learning of an association. For example, experienced drivers automatically respond to red lights by braking. By the time you make it to college, most reading has become automatic. Developing automaticity for familiar stimuli frees up valuable attentional resources that can be used for processing new and unexpected stimuli. Automaticity can, however, sometimes be an inconvenience, as you will see in the lab activity demonstrating the Stroop task.
Congruent vs. Incongruent Naming
There are only three experimental trials in this activity. Each contains a list with stimuli that you will have to name. For the first list, you will be shown a list of colored words. Press the begin trial button and your task is to read each word of the list aloud. When you reach the end of the list, press the “stop” button to stop the timer. In this list, you will notice each word matches the color it is written in (e.g., RED is printed in the color red). The word and the color are congruent in this first list. In the second part, you will also be presented with a list of words. Read each word aloud but ignore the color it is written in (e.g., if BLUE is colored green ignore the color and just read the word blue). In this list, the word and color are incongruent but read the word aloud. For the third and final part, you will also be shown an incongruent list of colored words (e.g., the word RED may be colored blue). For this list, name the color that the word is printed in. For example, if the word GREEN is printed in the color blue, say blue.
Reading Words vs. Naming Colors
Reading words is automatic. After years of reading in school and elsewhere, when words are presented to you, the first thing that you do is read them. The Stroop task demonstrates that the naming of incongruent colors (e.g., naming BLUE as “green”) takes longer than the naming of congruent colors (e.g., naming GREEN as “green”). Naming colors is not as automatic as reading because naming colors is something few people (e.g., artists and interior decorators) need to do as part of their everyday life. In doing the Stroop activity, you must suppress your automatic reading of the word and name the color it is presented in, which is difficult and slows you down. Reading is relatively automatic and requires less attention than naming the colors, when there is incongruency between the word and the color it is printed in.
Suppressing Automaticity
The Stroop effect has been demonstrated using a variety of stimuli and it can be shown that in any condition where an automatic process must be suppressed to make the response, naming will be slower than when no automatic process needs to be suppressed. Automaticity happens over time and reading happens later in development. If you asked a three-year-old who had not yet learned how to read to name the color a word is presented in on the congruent and incongruent lists, the child’s response times would be the same for both conditions because someone who has not yet learned how to read does not have to suppress the automatic process of reading.