Stroop effects lab report Abstract

Stroop effects lab report


The reason for the study was to investigate how matching the fontcolors of a stimulus word to the color named by the word affects thereacting time. Using the Cog Lab online library 2.0, 78 cognitivepsychology students participated in a Stroop experiment. During eachtest, the theresponsibility of the participants was to identify thefont of a word. The words alternated between the names of threecolors over 45 trials (MacLeod 1991). The students predicted that thefont color would affect the reaction time of the experiment. Asexpected, the important effect on the reaction was evidenced, t (77)=-7.96, p&lt.0.5. The process of automatic behavior is discussed tounderstand the Stroop effect and its repercussions.

When certain human behaviors frequently occur over a certain period,they become automated. Mostly, the automated behavior does notrequire conscious control. The process of automation is crucial sinceit allows frequent behaviors to be carried out unconsciously, at thesame time the attention is diverted towards other less familiartasks. Most psychologists who want to study the automated behavior doso by creating an experimental environment, in which automatedmanners, if present, will interfere with the conscious behaviors.Stroop performed the famously repeated experiment in 1935 (MacLeod1991). The experiment involved the presentation of subjects with thecolor names, in different colors of ink. The subjects were requiredto either read the word or identify the printed color. Therefore,Stroop found out that the subject took more time to identify thecolor than to read. Scientists have repeated the study several timeshowever it produces similar results. For that reason, thepsychologist concluded that the reading is more an automated processthat interferes with an individual’s state of recognizing the colorof the text.

However, in Stroop experiments some factors affect the outcomes ofthe experiment. The well-known factor is the correlation between thereading skill of a language and the amount of Stroop interferenceproduced. Therefore, this indicates that the more language islearned, the higher is its chances of becoming an automated process.The research conducted by Coderre(2008) revealed a similar degree of Stroop interferencebetween two writing systems of the same language. However, theresearch clarified that the two experiments were conducteddifferently (Coderre 2008). The argument isfundamental since it demonstrates how the Stroop effect is notexclusive to writing systems that are restricted to syllabic symbols.The research conducted by Iowa University students provided insightinto how the Stroop effect can be reduced (Stroop 1935). Theresearcher employed the social priming with the concept of dyslexiato reduce the amount of interference. Hence, this research is crucialsince it explains how the automated behavior is reduced by anotherautomated behavior rather than the conscious behaviors. Presently,due to the widespread of technology, the Stroop experiment isconducted in a computerized manner. The Cog Lab’s online laboratoryis used to access an application that creates the stimuli similar tothat found in the original study by Stroop in 1935. The independentvariables in the experiment of the study are whether the font colorand the word name correspond to the present stimuli (MacLeod 1991).The methodology of the current experiment is similar to that used byStroop given that in both experiments, participants are presentedwith stimuli consisting of the names of colors in varying fontcolors, and must respond to them. In the contrast to the Stroopeffect, this study was conducted through an online application thatautomated both group and individual data. Because of the previousexperiment’s results in the field, it is hypothesized that theparticipants will take long to respond to stimuli when the name ofthe color does not correspond to the font color.



Participants were 78 students from a cognitive psychology class atthe University of Iowa, who participated as part of their labrequirement.


A Wadsworth CogLab2.0 online laboratory task called the Stroop Effectwas employed in the current study. The participants completed thestudy on Apple computers in their computer laboratories.Additionally, the task was accessed through the Cog Lab web page andopened the computer screen`s window. The task window was completelyblack apart from the stimuli used in the undertaking, which weregreen, red, or blue. Additionally, the point of fixation and theinstruction text was white. The stimuli were in red, green, or bluein an approximate size 26pt (MacLeod 1991). Each trail consisted of apresentation of a stimulus just above the fixation point. At the topof the screen, the instruction “identifies the color of the fontand ignores the name of the word. Button the h key for red, the j keyfor green, and the k key for blue” appeared. The instruction textwas white, Arial, and approximately size 14 pt. Participants used thekeyboards provided to select their responses during the experiment.


Participants seated in the university’s computer lab. They firstentered their individual log- information to access the Cog Labexperiment. Subsequently, they read the Cog Lab Online instructionsfor the Simon task, which appeared in the dialog box. Theinstructions informed them on the keyboard to select depending on thefont color. Participants pushed the space bar when they were ready tobegin the first initial (Wheatley&nbsp2001).For each of the 45 trials, the participants were presented with thefixation point. After a second, a word appeared on the screen justabove the fixation point. During their time, the participantsselected the color of the stimulus font. If the stimulus font wasred, they selected their response by pushing the ‘h’ key. Oncethe response was entered, text appeared above the fixation pointindicating whether correct if the participant selected a correctcolor or not correction if the participant selected a wrong color.The text appeared below the fixation point instructing theparticipant to press the space bar to begin the next trail(Wheatley&nbsp2001). Once the participantpressed the space bar, the next trial commenced immediately. The newstimulus square appeared if the participant selected a color beforethe stimulus was present. The text reading “too early wait for thestimulus” appeared on the screen. The independent variables of thisstudy were whether the font color and the word name corresponded ornot. The dependent variables were the participant’s reaction timesto the stimuli presented. Using the above information, means andstandard deviation were calculated for the reaction times in eachcondition of the experiment.


When the color name and the font color were the same, the averageresponse time was 765.5393ms (SD=210.74277ms)(Wheatley&nbsp2001). On the other hand, when the color nameand the font were different, the average response time was 826.2637ms(SD= 212.84798ms) (Wheatley&nbsp2001).Therefore, figure 1 portrays the difference between the two groups.There was a significant difference in reaction times between the twoconditions t (77) =-17.96, p&lt0.5.


The results of the current research support the hypothesis. It wasexpected that the reaction times would prolong when the font colordiffered the word on the stimulus when the name and font were thesame. The expectation above is justified by the results obtainedbecause of a significance difference was found to exist between thereaction times and the two conditions (Goldfarb,Aisenberg &amp Henik 2011). The close examination of figure 1indicates that the average reaction time when the font color differedfrom the word name was, on an average, over 80ms longer than when thecolor and word were the same.

Therefore, the present research concurs with the ideas presented byStroop in 1935. The experiment was not sensitive in measuring factorssuch as gender and reading ability of the participants. Therefore, noother conclusions were drawn from the data collected. Lack of thereader’s important information hampered the usefulness of theexperiment. Most psychologists rebut the present experiment since itis prone to replication, which may render its lack of originality(Goldfarb, Aisenberg &amp Henik 2011).Possibly, the future experiment will benefit from adding othervariables to the experiment. Most preferably, ones that werepreviously examined in connection with the Stroop effect. Thepresent day experiment supports the theory through illustrating howreading is an automatic process that is capable of interfering withthe conscious of an individual (Wheatley&nbsp2001).Reading is an automatic process for it interferes with anindividual’s color selection process. The current test has beenmodified to experiment the cognitive development of an individual.The theory suggests how the brain analyzes information and in theprocess, specific pathways are developed for the tasks. Somepathways, such as reading are stronger others. The main variable ofthe experiment is the strength of the pathway and not the speed.Besides, automaticity is a function of each pathway’s strength(Goldfarb, Aisenberg &amp Henik 2011).Therefore, when the two pathways are activated concurrently in theStroop effect, interference occurs between the stronger and theweaker paths, especially when the path leading to the response is theweaker pathway. Most psychologists disregard the modern experimentsperformed on the Stroop effects because it ignores genders in itsperformance. For instance, the above experiment did not take intoconsideration gender issues. Gender issues are important in theexperiment since women are perceived to be more accurate inperforming the experiment than their male counterparts. If theexperiment were gender sensitive, they could have experienced achange in the speed accuracy. Likewise, the difference in reactiontimes and the gender could have been taken into consideration.However, the above experiment did not realize the difference. Theresult also explains the Stroop effects on different ages (Braet,Noppe, Wagemans and Beeck 2011). For instance, when people getolder, their automaticity for cognitive functions fades thus, thereaction times would have been faster. Additionally, if the educationbackground of the participants were to be taken into consideration,the cognitive functions would have experienced a faster fading in theparticipants with the lower education background. Thus, the aboveresults are not applicable to people of all cultures and age ranges,but this specific population used.

The experiment results are important determining how children learn,specifically how they learn to read. When students first begin toread, the task is not automatic. It only needs thoughts and effortsto perform the task. Therefore, the students cannot focus on what isbeing read, mostly on the process of reading(Braet, Noppe, Wagemans and Beeck 2011). As the students getolder, reading becomes easier and automatic compared to their youngerage. Furthermore, they can read without paying attention to what issupposed to be read. Consequently, teachers need to be careful withthe results of the experiment since they portray the slow developmentof a child. Moreover, the experiment does not portray automaticity ina bad way, but it is helpful in making the teachers realize thedevelopmental changes in a child.


Even if there were a few changes in the current experiment fromStroop’s experiment, the results would concur with the Stroop. However, the only difference is that the above experiment has beenautomated the process of reading.The first experiment by Stroopwas manually conducted, and it did not take much consideration of themodern technology. Therefore, both experiments are useful inexplaining the Stroop effect on the human development. The experimentwas successful it upgrades the previous Stroop experiment. Moreover,the research had some flaws such as lack of consideration to genderissues. Therefore, the gender issue should be taken intoconsideration to see how gender variation can affect the speed andresults of the experiment. Additionally, the experiment should alsoconsider the educational background of the participants because ithas many effects on the results.

Figure 1.Reaction time to stimulus as a function of the condition of thepresented stimulus.


Braet, W., Noppe, N., Wagemans, J., &amp deBeeck, H. (2011). Increased Stroop interference with bettersecond-language reading skill.&nbspTheQuarterly Journal Of Experimental Psychology,&nbsp64(3),596-607. Retrieved November 27, 2012, from

Coderre. (2008). The Stroop effect in kana andkanji scripts in native Japanese speakers: An fMRI study.&nbspBrainAnd Language,&nbsp107(2).Retrieved November 27, 2012, from

Goldfarb, L., Aisenberg, D., &amp Henik, A.(2011). Think the thought, walk the walk—Social priming reduces theStroop effect.&nbspCognition,118(2),193-200. Retrieved November 27, 2012, from

MacLeod, C. M. (1991). Half a century of research on the Stroopeffect: an integrative review. Psychological bulletin, 109(2),163.

Stroop, J. R. (1935). Studies of Interference inSerial Verbal Reactions. Journal ofExperimental Psychology,&nbsp18,643-662. Retrieved November 27, 2012, from

Wheatley&nbsp .(2001).&nbsp&nbspAutomaticity inaction. International encyclopedia of the social and behavioralsciences. (N.J. Smelser, P.B. Baltes, Eds.).:991-993., London:Pergamon