The brain’s functioning has always been an aspect of scientific interest, especially when considering the factors at play with respect to how one responds within specified variables. One such phenomenon involves the Stroop Effect; though the effect has been confirmed the specific cause of the effect is still under study. In trying to contribute to other studies seeking to uncover the phenomenon, a study with relevant variables and sound participants was conducted using a method comprising of a systematic design and procedure. The hypothesis for the study is that; when the color associated with the word conflicts with the printed color of the word the response time will be greater than when color association and printed word color match.
An individual is provided with a list of words and asked to systematically scan them to identify the specific printed color each whole word possesses respectively, regardless of the word meaning, which happens to spell a conflicting color word. The struggle to quickly and accurately overcome the inconsistence during color identification is known as the Stroop effect (Brown, Gore, & Carr, 2002). People tend to make mistakes and/or increase their response time during the exercise when word color is inconsistent with word meaning, such as when the word “orange” is printed in blue. There have been several variations of the Stroop experiment performed since the initial study with comparable results. There remains a debate as to the cause of the phenomenon, but it has demonstrated potential in a variety of research fields including clinical psychology, social psychology, neuropsychology, and reading (Brown et al., 2002). The current study seeks to expand on past research on this effect by incorporating new variables involving alternative word meanings and conditioned color association.
A great deal of research involving the Stroop effect has been conducted and replicated for decades (Brown et al., 2002). It is recognized that there are differing opinions as to what actually causes the Stroop effect in humans. To some, the interference stage occurs prior to the response stage in the brain, and the discord happens within the analyzing function of the brain (Goldfarb & Henik, 2006). To the contrary, at least one study has shown that the interference stage may be the same as the response stage, and that the mechanism of response is between brain analyzers. For that study, a color word, in colored print, was placed below a solid color bar and the goal was to match the word meaning and bar color exclusively. The results of that study showed that response time for identifying consistency increased when word color and word meaning matched, but word meaning did not match bar color (Goldfarb & Henik, 2006). The rationale behind this interference was that an irrelevant consistency was noted en route to the real measure, adding an inappropriate cognitive step.
The nature of the effect that words, of nearly any meaning, have on Stroop experiments is highly applicable to the current study. One study, in particular, sought to find out if the point of focus of one’s attention had an impact on the Stroop effect where words would lose their influence if not very near to the color (Brown et al., 2002). Contrary to their hypothesis, the study revealed that when a color patch was expected to be identified and there were only x’s or nonsense words nearby, reaction time was faster than when legitimate words were present, regardless of what the words meant. It was determined through multiple experiments within the same study that the point of focus and intention does not have a significant impact on word recognition. Participants were slowed by the involuntary and automatic reading of the legitimate nearby word (Brown et al., 2002). The study suggested that attention and intention likely play a stronger part in manipulating color naming rather than words. The major premise taken from these findings and applied to the current study was that word reading or recognition is likely to be involuntary and automatic, where the participant is reading the word and making assumptions even without intention.
Words, as the conventional studies show, often have a significant amount of weight when it comes to a Stroop effect, or its accompanying dilution (Brown et al., 2002). Can color exert a significant influence over the recognition of a certain word or obejct? A different study used words and objects with a high color diagnostic (HCD) and low color diagnostic (LCD) to test for the significance of color association and by its effect on word or object response time (Therriault, Yaxley, & Zwaan, 2009). That study used matching, inconsistent, and grayscale colors against the conditioned color association of the object, which yielded fast response time when color matched color association, and slower response time for both grayscale and incongruent colors. This supported their hypothesis and demonstrated that we do have conditioned color associations with HCD words and objects, which can even affect our ability to discern the shape and edges of the object in question, based on those assumptions (Therriault et al, 2009).
The current study was designed to expand past research on the Stroop effect by considering further the relationship between word meaning, word color diagnostic, and printed color. It follows that if the presence of words tends to interfere with information processing with regard to color, the true variable of concern, then the experiment must improve on past ideas through partial replication and the addition of alternative word associations and meanings. Improvements were made to the administration of the color blind test in relation to the experimental design. The studies discussed here were mainly within subject designs, and that was an effective model for this experiment. The variables manipulated in this study included word meaning and word color with regard to color association. The dependent variable measured was reaction time as recorded by an online HTML program to two decimal places.
Color blindness was a top concern as a confounding variable. Color blind individuals have conventionally been evaluated based on the errors they make when asked to identify particular colors, but studies show reaction time could be a more subtle but telling indicator as well because color blind individuals can learn to detect subtle hue variances that lead them to give the correct response even though they are legitimately color blind (Reed, 1949). This was important for us to consider in our study when administering the test, both in how we evaluate them and also how we interpret our results. Color blindness could have been a confounding variable even for the color blindness test if reaction time were not considered. One previous experiment accounted for color blindness but tested participants after the trail was completed (Therriault et al., 2009). This seems less efficient than the current study design because it allows for color blind participants to complete a trial only to have their results omitted from the study.
It was the hypothesis of the current study that when the color associated with the word conflicts with the printed color of the word, the response time will be greater than when color association and printed word color match. It was expected that the hypothesis would be supported; that the process of word recognition combined with conditioned color association would conflict with the response of the word color. Previous research, as described above, has confirmed the adverse effects that any word presence, especially with a high color diagnostic, can have on response time involving color identification.
The sample for this study consisted of college students from Heidelberg University; n= x. The gender distribution consisted of x male and x female participants. The age range was from x to x years of age, with a mean of x and a standard deviation of x. Participants were gathered mainly by word-of-mouth through the university’s psychology department.
The electronic materials utilized in this study consisted of four Dell™ laptop computers and flash data drives used to store and administer the test. Digital media included an HTML webpage which delivered the test battery and recorded response time to two decimal places. For records and evaluation there were paper spreadsheets given to each trial group, as well as a paper-based color blindness test (see figure x), an anxiety scale ranging from one (no anxiety) to ten (highest anxiety), copies of experimenter instructions, and pens/pencils for recording data. Also required for this experiment was a conference room with high-speed wireless internet access, IRB submission forms, and informed consent documents. Words were used that were considered to have a high color diagnostic and a neutral color diagnostic. For a list of words used in this experiment, see figures W.1 through W.3. Word or target colors used, with their corresponding HTML codes, included: purple (8D38C9), white (FFFFFF), blue (0000FF), red (FF0000), green (008000),yellow (FFFF00), orange (FF6600), and pink (F660AB). The test site was a conference room in Adam’s Hall, Heidelberg University campus.
The current study utilized a within subjects design where all participants received all aspects of the trial with the exception of a randomized test battery. The independent variables were word color and word meaning. Word color association refers to the level of color diagnostic assigned to a given word based on analysis of pilot tests and sample surveys taken prior to running participants officially. The goal was to match patterns and gauge the strength of conditioned word-color associations. Here word color refers to either black or one of the listed colors depending on the word list and its function in the given subtest (consistent, inconsistent, or neutral). Consistent refers to a subtest where word-color association and word color match, inconsistent refers to a subtest where word-color association differs from word color, and neutral refers to the use of words that are without a defined color diagnostic. Considering the possible orders for the record, order one meant the consistent subtest came first, order two meant the inconsistent subtest came first, and order three meant the neutral words appeared first. The dependent variable was reaction time as measured in seconds to two decimal places by a web-based HTML program designed to administer the experiment under the control of the experimenter, in cooperation with the participant.
Prior to administering the test, participants were offered informed consent forms and the opportunity to ask questions within reason about the experiment. Students were assigned to a test pair of experimenters, which formed four different groups that could run participants efficiently. Upon arrival at the test site, participants completed a demographic questionnaire, an anxiety scale, and a color blindness test. Those who tested positive for color blindness were respectfully omitted from participating in the study.
Participants proceeded to one of four pairs of experimenters, each having their own laptop computer to run participants efficiently. After completing the color blindness test, the remaining participants were asked to carefully read the instructions on the computer screen and respond to a preliminary color word exercise for practice to ensure they understood the procedure. The final step before beginning the word-color association Stroop test was the reading comprehension exercise where the participant would be instructed to read a series of words in black color, modeling the format and procedure for the true test. When the subject completed the reading comprehension phase, they were informed that the actual test would begin on the next page and they were to respond with only the color of the words, respectively, while reading from left to right.
After the subject acknowledged the instructions, they were told the test would begin. The experimenter clicked on the appropriate button to start the test, which brought up an intermediate screen that read, “get ready.” The purpose of the intermediate screen is to engage their attention on the screen, knowing the timed test was imminent. After approximately three seconds, one of three sections of the test (neutral, consistent, inconsistent) appeared in random order. The subject would read the word colors respectively from left to right until they completed the exercise. While in progress, one experimenter would track correct/incorrect responses by marking the corresponding, paper-based word list on hand, as the other clicked the appropriate buttons on the web-based test in cooperation with the participant’s progress to stop the timer for each subtest. Clicking the “finished” button brought up a new data window indicating the response time in seconds to two decimal places (e.g., 12.74 seconds). The response time was recorded at that moment by an experimenter on a paper spreadsheet and the subject was told, “you will again read the words from left to right on the next screen.” To proceed, one experimenter would close the timing window once a record was made and click on “continue” to move to the next subtest, which was again preceded by an intermediate “get ready” screen. This process was repeated until the third and final response time was recorded.
Upon completion of the word-color test battery, each participant completed the anxiety scale a second time and responded as to whether or not they had heard of the Stroop effect or experiment before. This acted as a manipulation check to test the strength of the effect independent variable. They were consulted to see if they had any further questions regarding the experiment and then informed as to how they could obtain the results of our experiment when available. Participant test results materials were stapled together and the random order generated for that participant was recorded for analysis.
A 3 x 3 two way mixed analysis of variance was conducted to determine whether inconsistent word lists would lead to greater reaction times in a Stroop effect reading task. N = 71. Results of that analysis indicted a main effect for order, F (2, 74) = 3.97, p = .02, and also for the interaction between list type and order given, F (4, 148) = 4.04, p = .004. Results did not indicate a main effect for list type, F (2, 73) = 1.93, p = .15. Mean reaction times for the consistent, inconsistent, and neutral lists were 12.15, 11.74, and 11.92, respectively, with corresponding standard deviations of 2.17, 2.44, and 2.11. These data indicate the greatest reaction time was found in the consistent word list.
Disparities were found for the “consistent”, “neutral” and “inconsistent” responses. It took longer to react in the congruent subtest than all others. The analysis of subtests revealed that it took longest to respond when word-color association and word color was a match.
The experiment was important as it expanded on the Stroop test by seeking to establish other relevant factors that play a significant role in affecting a person’s response time, which in turn will go a long way in determining how a person’s brain works, with respect to the analysis of conditioned words. However, in this particular study the hypothesis that; when the color associated with the word conflicts with the printed color of the word the response time will be greater than when color association and printed word color match, was not supported by the results attained. Unlike the case in the basic Stroop test, where inconsistency of the word color and word meaning caused an increased response time, the inconsistency between the word-color association and word color does not cause an increased response time with respect to the relevant variables used.
Further, since the greatest reaction time was found where word-color association and word color matched, it is possible that the participants were slowed by the low profile of the words in this particular subtest, a factor that added an inappropriate cognitive step (Goldfarb & Henik, 2006). On Luo’s 1999 study;
In which on each trial a colored bar appeared on a computer screen above a color word displayed in color. Participants were asked to decide whether the word’s meaning (WM) matched or did not match the bar’s color (BC). Luo compared reaction time (RT) in the congruent condition, when the word’s color (WC) was the same as BC, with RTin the incongruent condition, when WC differed from BC. For both ‘‘same’’ and ‘‘different’’ responses, matching between WM and BC was slower when WC and BC were incongruent rather than congruent. (Goldfarb & Henik, 2006, p. 96)
Goldfarb and Henik (2006) outlined Luo’s conclusion by stating “if the [printed color] and the word are displayed in the same color, then they activate the same color representation and if they are displayed in different colors, they activate different color representations” (p. 96). Therefore the conclusion for this study, based on the response time of the participants, tends to indicate that the interference stage may be the same as the response stage, and that the mechanism of response is between brain analyzers (Goldfarb & Henik, 2006).
Compared to the various experimental studies on the subject of Stroop Effect, this particular study goes to show that more should be done especially with the incorporating new variables involving alternative word meanings and conditioned color association, for instance, variations of the BC. The results obtained should be considered in comparison to MacLeod and Mac-Donald’s (2000) task-conflict theory (Goldfarb & Henik, 2006) and others that focus on the alternative hypothesis which considers matching between WM and WC an irrelevant task ,” (Goldfarb & Henik, 2006, p. 98). More should be done in terms of analysis and variations of studies to ensure more contributions to the understanding of the Stroop Effect phenomenon.