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Running Head: INVESTIGATING THE IMPACT OF INTERFERENCE ON COLOR
IDENTIFICATION USING THE STROOP EFFECT

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Investigating the Impact of Interference on Color Identification Using the Stroop Effect

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Alexis Fernander
Candidate No. 0144
Seminole High School
February 17, 2015
IB HL Psychology
Mrs. Andrea Zara

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Word Count: 1433

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INVESTIGATING THE IMPACT OF INTERFERENCE

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CONTENTS
Abstract……………………………………………………………………………………………3
Introduction……………………………………………………………………………………..…4
Method…………………………………………………………………………………………….5
Design: 5
Participants: 5
Procedure: 5
Results………………………………………………………………………………………..……6
Discussion……………………………………………………………………………………..…..8
References………………………………………………………………………………………..10
Appendices……………………………………………………………………………………….11
Appendix A: 11
Appendix B: 13
Appendix C: 14
Appendix D: 16
Appendix E: 17

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INVESTIGATING THE IMPACT OF INTERFERENCE

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Abstract
Research on interference and information processing began in the late 1800s and has continued for nearly 200 years. In 1935, J. R. Stroop published an article on attention and interference that has become a pillar of psychological research. Stroop investigated whether ink color being incongruent with the word presented had any effect on a person’s ability to name a color. He tested seventy college undergraduates, (Stroop 1935) having them read four stimulus cards on which the colors purple, brown, red, blue and green each appeared with incongruent colorings, as well as in black ink, with both forms printed in a forward and reverse order. Stroop found that it took participants 2.3 seconds longer on average to read the experimental colored cards, but determined this minimal increase to be inconsequential. This led him to conclude that incongruent colors did not in fact produce interference (MacLeod 1991, p. 164).
The aim of this experiment was to examine the reliability of Stroop’s results. The original research was replicated using the students of a ninth grade english class of eighteen students. The findings of the replication supported Stroop’s conclusions, as there was an average difference of only 1.3 seconds observed between the colored and black forms.

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INVESTIGATING THE IMPACT OF INTERFERENCE

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Introduction
Psychologists have been investigating the discrepancy in time for reading color names and naming colors since the 1880s, and a number of studies have been offered to explain the phenomenon in terms of interference, or the interruption of processing due to inhibiting stimuli.
Perhaps the most famous interference study was conducted in 1935 by J. R. Stroop. He established a set of three experiments in order to determine the effects of color stimuli on word stimuli and vice versa, as well as how practice would affect reaction times in both situations.
In the first of these experiments, Stroop created four 10 x 10 stimulus cards on which the colors purple, brown, red, blue and green appeared in 14 point lowercase franklin font, twice in every row and column. Each word was printed on the first card an equal number of times in the other four colors, and the order was replicated in black ink to produce the second version. These cards were then replicated in reverse order for the third and fourth versions. After a 10-word practice,
70 participants were timed as they read the words printed on the 4 cards aloud as quickly as possible, with instructions to leave no errors uncorrected. Half of the participants were given the four cards in the order control form 1, experimental form 1, control form 2, experimental form 2, with the cards printed in black ink being the controls and those in color being experimental. The other half were given the test in reverse order. Of all the participants, none made more than 4 errors in their naming of the colors, which Stroop concluded was negligible. (Stroop 1935)
The aim of this experiment was to investigate whether or not incongruence between the color a