Stroop Interference

The Stroop effect is demonstrated by the reaction time to determine a color when the color is printed in a different color’s name. Participants respond slower or make more errors when the meaning of the word is incongruent with the color of the word. Despite knowing the meaning of the word, participants showed incapability of ignoring the stimulus attribute. This reflects a clear instance of semantic interference and an unfathomed failure of selective attention (Stroop, 1935).

An interesting challenge arises when a task such as color naming is identified as both controlled and automatic, by varying the other task involved. Color naming is identified as a controlled process when the other task is word reading, but as an automatic process when the other task is shape naming. Cohen, Dunbar and McClelland (1990) proposed an alternative explanation of the Stroop effect, which does not distinguish between automatic and controlled processing. Instead, they proposed that automaticity is a range, and that Stroop interference depends on the relative degree of learning the particular tasks, not on processing speed.

Ullsperger, Bylsma, and Botvinick (2005) investigated whether the findings of Mayr, Awh, and Laurey (2003) can be replicated and how much they can be shown across different task performances. Their specific study was motivated by a prior experiment where Gratton, Coles, and Donchin (1992) found that after an incompatible type trial reaction times were reduced and target processing occurred more frequently than flanker processing on the next trial. Botvinick, Braver, Barch, Carter, and Cohen (2001) believed that this follows the conflict monitoring hypothesis where incompatible trials involve a conflict with the response leading to greater top-down information processing (Botvinick, Nystrom, Fissell, Carter, & Cohen, 1999). However, Mayr et. al (2003) argued that the congruency sequence effect found by Gratton et al. (1992) was due to repetition priming because of stimulus repeats in a flanker task. This may have led to a faster reaction time with repeated trials. Mayr et al. (2003) used two experiments to present evidence for their argument. Both experiments failed to show the effect found by Gratton et al. (1992) when target and stimulus items did not repeat from trial to trial.

The Stroop effect was tested on four different tasks. Nineteen Queens College students were recruited by flyer, and each were assigned to a word reading task, color reading task, color inhibition task, and word inhibition task. They were timed using a stopwatch function on a cell phone, to name the color, or word to the quickest of their ability. In the order from longest reaction time to shortest: inhibition color naming task, color naming task, inhibition word reading, and word reading. This study shows that people can read words more quickly than they can name colors, and that inhibiting an automatic response to color/word tasks will take longer to do than tasks that do not involve inhibition.

The Stroop experiment by J. Ridley Stroop in 1935 was performed in order to analyze the reaction time of participant’s stimuli and desired results while also obtaining a collective result of color interference and word reading(Stroop, 1935; Lee & Chan, 2000). In the experiment three forms of the test were given, the first consisting of color patches, the second had the color words printed in black and the other was an incongruent test beaming the color did not match the color word

However, evidence from a recent series of experiments conducted by MacLeod and Dunbar (1988) suggests that the processes involved in the Stroop task may have not been inadequate. In their experiment they taught participants to use color words as names for arbitrary shapes that actually appeared in a neutral color. After 288 trials where there was a 72 trials per stimulus, participants could perform this shape-naming task without difficulty. At this point, the effect that ink color had on shape naming was tested by presenting participants with conflicting and congruent stimuli for example, shapes colored to conflict or agree with their assigned names. Ink color produced large interference and facilitation effects. However, when the task was reversed, and subjects were asked to state the color of the ink in which the

The Stroop test consisted two major posters of word lists: Incongruent list and Neutral list. Each poster included 20 words in 2 columns of 10 words each. All letters were stenciled, capitalized and 1 ¾ inches high. Both incongruent and neutral words were listed on the 56 x 71 cm posters Stopwatch with 0.01-second accuracy was used to time to measure how long participants took to read both incongruent and neutral word lists, which is a dependent variable for this experiment.

In the Stroop task, participants are asked to name the colour of the ink that a colour word is written in, while ignoring the written the word (Goldfarb et al., 2011; Raz et al., 2006). The task is comprised of congruent words, where the ink colour and the written word match and incongruent words, where the ink colour and the written word do not match. The Stroop task has illustrated that participants respond slower and less accurately when the word is incongruent compared to when it is congruent (Goldfarb et al., 2011; Raz et al., 2006). The difference in the accuracy and speed of responses between the congruent and incongruent words is called the Stroop Effect (Goldfarb et al., 2011; Raz et al., 2006). Research has suggested that this occurs

We often tend to live our everyday lives without paying much attention to the factors that contribute to our every movement and function. Have you ever wondered what triggers your brain to complete simple tasks, such as reading road signs, or knowing how to follow a guided set of instructions? John Ridley Stroop became specifically interested in the part of the brain that measures selective attention [1]. Oftentimes, in order to maintain balance, the brain will carry out the action that is most common and easy and will stop the action that will take more work and effort. The process explained in the previous sentence is known as inhibition, and it regularly occurs in our minds [2]. Stroop gave participants a list of colors, such as green,

In the 1930’s, psychologists wanted to better understand how the brain processes presented information. To take it a step further, they wanted to see what happened when conflicting factors were presented and how the brain would process it. Would there be a delayed response? Would there be an error when giving the response? Psychologists were especially interested in how conflicting factors would inhibit the rate of impulse transmission in the nervous system (Eberle, 2012) and in 1935 John Ridley Stroop came up with an experiment to test the response rate of people when they were presented with conflicting factors.

While taking the Stroop test your brain is trying to say the word because words are a stronger influence than colors. This then causes conflict in your brains, mental tasks. When you look at one of the words, you are seeing both the color and an opposite meaning which forces your brain to make a decision on which one it should focus on. John Stroop’s theory is that interference happens because people can read a word faster than saying a color because color is more complex, taking more time to correctly

The article by Avital-Cohen and Tsal (2016) discussed the flanker task experiment, which asserted that distractor interference happens unconsciously as a result of focused attention toward the target. The results from the original flanker task indicated that participants had slower responses for incongruent trials, since the distractors are inconsistent with the target and would require a different response (Avital-Cohen & Tsal, 2016). However, Avital-Cohen and Tsal (2016) questioned the findings from the flanker task experiment. They decided to challenge the idea that only the target stimuli receives top-down processing, and not the distractors (Avital-Cohen & Tsal, 2016). The first experiment aimed to test whether the distractor interference is purely bottom-up processing as claimed in the flanker task. The experiment manipulated participants’ expectations of the target using the context effect - a type of top-down processing - by changing the distractors to be either letters or digits (Psych 240 lecture, 9/21/16). Then, the researchers conducted a second experiment and eliminated the ambiguity of distractors. They wanted to test whether the result from experiment 1 was caused by an overall bias or the ambiguous distractors. In experiment 2, the researchers predicted that they would obtain similar results to the first experiment only if the results were due to an overall bias effect (Avital-Cohen & Tsal, 2016). This study allows us to deepen our understanding of available

In 1935, John Ridley Stroop conducted an experiment at George Peabody College for teachers in the United States. Stroop used 70 college undergraduates as subject in his experiment, he compared times for reading names of colours and naming colours themselves. The aim was to determine if the colour of the word affected the ability to read it. In the experiment, there was three different conditions. In the first condition participants were asked to read words as quickly as possible whereas participants had to name the ink colour in which each word were printed as quickly as possible in second condition. In a third condition (the incongruent condition), participants had to name the ink colour in which each word was printed, but in this condition the words themselves were colour names. For example, the word ‘GREEN’ was presented in the colour orange and you were required to read this colour instead of the word itself. Stroop found that the participants were much slower at naming the ink colours when the stimuli were themselves colours as (third condition), indicating that a possible explanation for the Stroop effect is that people quickly and automatically process the meaning of the word.

This study serves to investigate the phenomenon of the congruency sequence effect (CSE), often called conflict adaptation. A substantial amount of literature in the field of cognitive neuroscience has been dedicated to investigate the underlying mechanisms behind the CSE. Currently there are two competing views that try to answer this phenomenon: selection for action and response inhibition. Selection for action suggests that the brain focuses more on the target to cope with distraction. Competing views, such as response inhibition, instead suggests that the brain ignores distractors. The current study uses a prime-probe word task to try to distinguish between the competing accounts. To differentiate between the two hypotheses, we have employed the technique of varying the time intervals separating the distracters from the target. This increased time interval virtually eliminates the overall congruency effect and allows us to examine the underlying mechanisms. By combining this unique methodological approach and accounting for various confounds, we observed a negative congruency effect after incongruent trials. We believe that the increased time intervals separating the distracters and targets are responsible for the subjects’ ability to fully inhibit the response activated by the distracter. These findings provide compelling evidence that support the control process of response inhibition in the absence of learning and memory confounds.

We are replicating J.R. Stroop’s original experiment The Stroop Effect (Stroop, 1935). The aim of the study was to understand how automatic processing interferes with attempts to attend to sensory information. The independent variable of our experiment was the three conditions, the congruent words, the incongruent words, and the colored squares, and the dependent variable was the time that it took participants to state the ink color of the list of words in each condition. We used repeated measures for the experiment in order to avoid influence of extraneous variables. The participants were 16-17 years of age from Garland High School. The participants will be timed on how long it takes them to say the color of the squares and the color of the words. The research was conducted in the Math Studies class. The participants were aged 16-17 and were students at Garland High School. The results showed that participants took the most time with the incongruent words.