Stroop Effect and Selective Attention

Abstract

The research examines Stroop effects among people of different ages and gender. It employs three various Stroop tasks named Card A, Card C, and Card B. Each Stroop task has a different level of conflict or interference in participant responses. The research is conducted on 100 participants, with 50 young people and 50 older persons. The participants were selected from a school setting following exclusive and inclusive criteria like a normal vision without color blindness. The main research question for the study is to find the relationship between age and gender on the Stroop effect. The study’s outcome shows that when individuals get older, their Stroop task time difference increases and results in a substantial variance between women and men. The materials used in the study to ensure successful results were obtained colored markers and computers to aid in assessing the Stroop effect between adults and young persons. The research had limitations, such that it did not reveal how the version of the color-word affected the tested results because a recording of reaction time was manually done. The research study was essential because it can be used in psychology to provide in-depth information on adults’ and children’s brain processing.

Introduction

The Stroop effect is a phenomenon that discloses information regarding how the brain of individual processes information when there is interference. Psychologist John Ridley Stroop first coined the Stroop effect in the 1930s as a predisposition of an individual to encounter difficulty identifying the color of a printed word when the word spells the name of a different color (Goldfarb et al., 2011). The simple outcome played a vital part in clinical psychology and psychological study. In the original work of Stroop, he employed three aspects colors’ names imprinted in black ink, colored names engraved in various ink than the colored named, and squares of every specified color. Two parts of the experiments were then conducted. In the initial study, the participants were requested to read the color imprinted in the blank ink, after which they were requested to read the words imprinted, regardless of the color imprinted (Poguntke et al., 2019). In the second test, Stroop used the ink color as an alternative to the written word such that red would have been printed in green, and participants were asked to specify the color green instead of reading the word red. In this section, also, the participants were requested to determine the color of the squares.

Stroop established that participants took more time before finishing naming the colored words in the second test than the time taken to recognize the color of the rectangular boxes. In the second test, participants also took a long time to detect ink colors than when they were required to read the imprinted word in the first test (Penner et al., 2012). Stroop then recognized the effect as an interference instigating a delay in color identification when different from the imprinted word. The finding of the Stroop effect resulted in the creation of the Stroop test, which was then used in the psychology field to assess the potential to constrain intellectual interference occurring when the processing of explicit colors’ characteristics delays the simultaneous processing of a second color feature (Raz et al., 2006). Therefore, the Stroop test formed the most straightforward form of the initial experiment presenting unlike information about participants’ color of words differing from the imprinted word. The Stroop test is useful as it helps measure selective attention.

A few theories explain the existence of the Stroop effect, such as speed of processing theory, automaticity, selective attention theory, and parallel distributed processing theory. Selective attention involves choosing the type of information to grant access for further awareness and processing and those to be ignored (Roy et al., 2018). Regarding the Stroop effect, recognizing words’ color takes more devotion than merely reading the writing. Therefore, selective attention theory proposes that the brain of individual processes the written information instead of the colors themselves. On the other hand, cognitive processing entails controlled and intuitive thinking (Wang et al., 2017; Ward et al., 2021). Stroop effect means the brain potentially recites the term since reading is perceived as an automated process than identifying colors. Written words can be processed faster than processing colors, making it harder to recognize the colors once the words have been read. The brain also creates diverse pathways for diverse tasks, which plays crucial roles that are easier to name the text or color.

There is continued research on the Stroop effect by psychologists, finding the underlying causes for the phenomenon. However, factors have emerged affecting the outcomes, such as the variance in the Stroop effect among men and women. During early studies, Stroop had identified that women were less likely to be distracted than men (Raz et al., 2006). Older persons have also been identified to have longer delays in processing than younger persons. However, studies show a lot regarding how individuals process information and assess their capabilities to override intuitive thought. Studies show that the effect identified in the Stroop task provided a clear understanding of the potential of persons for discerning attention (Scarpina & Tagini, 2017). The Stroop test forms a valuable part of evaluating interfering control and task set directing among adult people with ADHD and assessing selective attention of people in traumatic brain injury.

Several studies established that Stroop interference could be decreased; thereby, it has inferences for people’s knowledge skills, capability to form habits, and multitasking (Savaş et al., 2020; Scarpina & Tagini, 2017). In the Stroop effect, when individuals understand how their brains make connections, it becomes easier to overcome interference, reach more logical conclusions, and incorporate controlled thinking. Therefore, the Stroop effect has continually played vital roles in research that entail intellectual processing, selective attention, controlled and intuitive thinking. In this study, the research question is how the Stroop effect is correlated with age. It is hypothesized that as people get older, their time difference between Stroop tasks increases.

Method

Participants

The study comprised of 100 participants who were divided into two groups according to age (young and adult). The two groups’ age groups ranged as follows: young (18- to 25-years old) and old (60- to 75-years old). Entire young participants had normal vision, or their vision was altered to normal. Caregivers and parents of young adults confirmed that no young person experienced school issues or colorblindness problems because of attentional shortages. The recruitment of young participants into the research study was done through advertisements on school notice boards. Together with their caregivers, all young people were given an informed consent to sign after being informed of all that the research involved, including its implication to them. On the other hand, adult participants volunteered to participate after attending a preliminary study in applied psychology. All the adult participants had standard vision without incidences of colorblindness. Before enlisting participants into the research, they were given an informed consent form which they signed without any manipulation.

Materials and Procedure

In the research, participants completed three unlike types of Stroop tasks. The first test involved a task with word for color whereby colors word blue, yellow, green, and red appeared on a sheet of paper as a color name. All the words in this first test were printed in black. Each form comprised 50 black words organized in ten rows and five columns. Each participant was tasked to read the color name as fast as possible, and recording was done for the time taken to read all the 50 words. Repetition of the Stroop task was then done three times with a recess of five minutes to examine test-retest consistencies.

The second task was named Card C, in which rectangular color boxes were presented in ten rows and five columns, each printed with either color blue, yellow, green, and red arranged in a manner that caused conflict conditions. The participants were allowed to name each rectangle’s color loudly after each row or column as quickly as possible. The process was repeated three times. A similar test was also arranged on a computer screen where applicants were directed to press one of 4 push buttons conforming to the four possible imprinted colors as fast as possible. The color names were offered in white typing at the bottommost of a mainframe screen to facilitate recognizing the right button. This test was also done by presenting color prints of red, yellow, green, and blue on paper arranged in ten rows and five columns.

The third task involved color-word that matched colors blue, yellow, green, and red with color names that resulted in conflict conditions appearing on the computer screen. The participants were responsible for naming the color of the print while the word spelling was different. The participants were required to follow the lines as quickly as possible, naming out loudly the color of each word and not what the word says. After reaching the end of the page, the process was repeated three times, recording the time taken to complete the task. All participants performed assigned tasks on color-word. They used computerized versions testing the reliability and stability of performance by allowing a time interval of five minutes between tasks. The results obtained from the research were analyzed using Pearson correlation and t-tests.

Results

The descriptive statistics of the research data set were determined whereby young participants had a mean age of 21 years and a standard deviation of 1.11, while adult participants had a mean age of 67.4 years and a standard deviation of 5.8. The research study showed a significant t-test variation amongst words matched with their corresponding color. The results for Stroop effects were as follows; it took 17.166 seconds to run a preliminary test 1 Card A. 54.91 seconds to complete Stroop trial 1 Card C, 48.24 seconds to complete practice trial 1 Card B, and 16.663 seconds to complete practice trial 2 Card A, 37.599 seconds to complete Stroop Trial 2 Card C, and 44.21 seconds to complete Stroop Trial 2 Card B. The results show that older people take longer to recognize congruent stimuli and incongruent word colors than young people. There was greater variability in response between the participants because of the large standard deviation for the group. The difference among the groups involved in the research was analyzed based on the differences between them using a t-test for independent samples such that the results were t (100) = 28.32, p ≤ 0.035. The values of time taken to READ word and SAY colors were significantly higher for participants who belonged to the aged group than for younger persons. Due to this variation, older participants recorded a higher magnitude of the Stroop effect than young people. Pearson correction was as follows r (100) = 0.802, p=0.035. The correlation showed an association between adults and young people regarding the Stroop effect. Young people recorded an excellent Stroop effect on color-words tests such that the t-test was as follows t (50) = 2.96, p ≤ 0.001, while adults showed significant outcomes in computerized versions recording a t-test of t (50) = 0.57, p ≤ 0.001.

Discussion and Conclusion

The research aimed at exploring the Stroop effect among adults and young people using three different tasks. In both groups, the version of the Stroop task initiated an interference effect to a changing degree. Stroop task card B recorded the most substantial impact, with Card C results recording higher differences in adult participants than young participants. In the Stroop task, A, C, and B, the time taken to both stimuli was longer, with greater magnitudes of Stroop effect in older persons than the younger participant. Older people have declined capability of processing speed that inhibit information processing causing poorer outcomes of Stroop tasks than younger persons (Roy et al., 2018; Raz et al., 2006). However, there was also a correlation between the effect of aging on the speed of response and the accurate measurement of outcomes. Older participants are likely to focus on accuracy rather than speed, resulting in delayed response to Stroop tasks. More trials were used to guarantee the validity of the Stroop test result because presentation stimuli style had a more substantial effect on test validity. Based on sex differences, research shows that there has been no report on the impact of sex distribution on the Stroop effect. However, psychologically there can be a slight advantage to female such that they possess better verbal abilities than men, which make them name the ink colors faster.

In conclusion, all the Stroop tasks caused various interference effects, leading to considerably more interference than other tasks across both groups of participants involved. There was more interference in the color-word matching Stroop task C than the Card B task. Also, it recorded the highest t-test reliability among all the participants involved. There was, however, a lack of significant association with color-word tasks among adult participants. It can be concluded that Stroop tasks resulted in interferences that were diverse among adults and young participants.

The study had limitations, such that the sample size of participants in the group was not equal, which likely influenced the outcome of the study. Also, the research did not reveal how the version of the color-word affected the tested results because a recording of reaction time was manually done. Also, recording separately incorrect trials followed with the counterbalanced design of the study would have resulted in limited reaction times for computerized tasks. The study implies future studies such that from the findings, they can be used in psychology to provide in-depth information on the brain’s processing among adults and children. In the future, when designing the study of the Stroop effect, it would be essential to include brain mechanisms that help in elucidating on Stroop effect factors in terms of anticipation and control. The extent to which test results are affected by color-word versions should be revealed and incorporate a similar sample size among study groups.

References

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Wang, K., Wu, W., Zhong, H., & Cheng, J. (2017). Gender differences in performance for young adults in cognitive tasks under emotional conflict. Neuroscience letters, 661, 77-83.

Ward, N., Hussey, E., Alzahabi, R., Gaspar, J. G., & Kramer, A. F. (2021). Age-related effects on a novel dual-task Stroop paradigm. PloS one, 16(3), e0247923.

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