Stroop Effect and the Influence of Numeration - Research Paper Example

? STROOP EFFECT AND THE INFLUENCE OF NUMERATION Your first middle initial and Academic and location Stroop effect has been previously reported to cause delays in response latency from conflicts in visual cues and intended tasks, now labeled as incongruent conditions. Differences between response times (RT) in neutral or congruent conditions compared with incongruent conditions were previously reported due to automation processes, implying the dominance of automated processes such as reading or other visual tasks. This study’s purpose was to find out if Stroop tests that use numbers display effects similar to colored Stroop tests in affecting response times of participants. Numerical Stroop effect was tested in a sample population of mixed genders and ages (n=121, males=32 and females=89, age range=15-47 years). Independent variable is the four categories of tests, while the dependent variable was the response times of the participants, measured in seconds. This study obtained RT means for each test, with RT from incongruent conditions (condition 3 mean=18.1s, SD=3.4s) being significantly-different compared with neutral (condition 1 mean=11.1 s, SD=1.9s, and condition 4 mean=12.2s, SD=2.2s) and congruent conditions (condition 2 mean=13.1s, SD=1.9s). The test results further supports earlier Stroop effect studies regarding observable delays in response times caused by Stroop inhibition among people. Stroop Effect and the Influence of Numeration Delays in response times due to distractions that can be audio-visual may seem out of the ordinary, but this phenomenon actually has a long history in the realm of psychology. This phenomenon is known as the Stroop effect and is considered to be one of the most recognizable or at the very least notable phenomenon that students of Psychology or Introductory Psychology courses can recall due to the instant and observable response delays caused by conflicting cues (MacLeod, 1992). One of the most well-known Stroop test is telling the ink or font color of color words after reading a list of neutral-colored words as fast and as accurate as possible. For example, reading a list of color words printed in black, then reading colored color words such as saying the red-inked word “blue” is colored “red” or of the word “green” colored with a green font color as “green”, and so on, with most participants having slower response times or response latency to the test involving colored fonts compared to the neutral-colored texts (Hintzman, et al., 1972; MacLeod, 1991; Stroop, 1935). Experiments on Stroop Effect The Stroop effect was not originally coined or established by the researcher whose name was used for this term, but John Ridley Stroop’s experiment on the individual and interacting effects of color words and the colors used for these color words generated more theories on the development and automation of cognitive processes and responses among humans through observation of the effects of interferences on attention to stimuli due to conflicts in cues (Cohen, Dunbar, & McClelland, 1990; Hintzman, et al., 1972; Liotti, et al., 2000; MacLeod, 1991; Simon & Berbaum, 1992; Stroop, 1935; Tzelgov, Henik, & Berger, 1992). Psychologists studying the Stroop effect mostly worked on how the interference affects cognitive processes in the brain and is resolved through repetition of stimuli and a development of an automation process from such stimuli. This comes from the ability of several parts of the brain nearly getting simulated at the same time and causing confusions, as supported by some experiments on Stroop effect that produced similar interferences as well even though the tests did not use a combination of colors and words in a single language but other symbols such as numbers and shapes, as well as words from other languages (MacLeod, 1991; Stroop, 1935; Tzelgov, et al., 1992). Many studies have been conducted in order to prove or disprove the results of the initial Stroop experiment, and studies found out that the Stroop effect was the result of the greater focus and usage of visual-spatial networks over other neural processes, turning it into an automated cognitive process which can easily compete with other thinking tasks (Cohen, 2009). In addition, with regards to numeration or numbers, some studies have shown that the number’s identity or name is recalled much more easily than performing the task intended to it, which is not only attributed to be attributed to the automation of reading due to visual stimuli, but also because of the possibility that the shapes of the numbers themselves contribute to interferences due to similarity in shapes, as well as the integers not functioning as quantifiers but rather as linguistic and hence, visual symbols (Cohen, 2009; Windes, 1968). Such conflicts can cause even more confusions and conflicts among brain regions, which can further contribute to a slower reaction time to visual stimuli combined with other sets of instructions such as numerations. There were considerable increase in response times during Stroop tests, but it is possible to overcome these long response times and become reduced. Some experiments which conducted tests repeatedly and recorded some changes in the response latency or response times for each trial were able to show that although initial tests may show a certain amount of increased response time due to interferences such as conflicts due to the competition of color and word information or the suppression of either one as the task needs, these can be overcome through efforts such as repetition of similar tests, hypnosis or suggestion, or through making a schemed questionnaire to generate attention bias among participants (Cohen, et al., 1990; Lundh & Czyzykow-Czarnocka, 2001; Raz, et al., 2006; Tzelgov, et al., 1992). These can be attributed to changes in the brain’s processes from conflicts in the working memory resulting from the alternate activations of two brain regions: the cingulate cortex which is involved with visual stimuli and the left temporo-parietal cortex which is involved with the verbal and word processes, to the use of only one of either brain region due to automatic processing as a result of the decreased influence or need of working memory (Cohen, et al., 1990; Liotti, et al., 2000). Whereas competitions between brain regions can affect Stroop responses and inhibitions among individuals, it is possible to overcome Stroop inhibition through repetitive exposure to similar stimuli, resolving the conflict between two activated brain regions, reducing the effects of working memory, and developing an automated response to the stimuli, which in time causes a selective activation of only the brain region needed to complete the task (Cohen, et al., 1990; MacLeod, 1991; Simon & Berbaum, 1992; Tzelgov, et al., 1992). Study Objectives, Rationale and Hypotheses This study’s primary aim is to assess whether or not Stroop responses and response times (RT) of participants are affected during the use of numerical Stroop tests. Participants were tasked to quickly read and count numbers and number of digits regardless of the symbols or numbers used for each test item, and they were subjected to Stroop tests of variable conditions, ranging from neutral conditions such as reading each number in each number sequence and counting how many X’s are in each item, to incongruent and congruent conditions such as counting digits in conflicting (e.g. 3333= four digits) and non-conflicting (e.g. 22= two digits) number sets. This makes the four test conditions to be the study’s independent variable. Meanwhile, the unit of measure for this study is measuring response time in seconds (s) for each of the tests involved, making RT the study’s dependent variable. This study expects that the participants will have short RT during the first two neutral conditions (conditions 1 and 2) and in the congruent condition (condition 4) due to a lesser need of processing the stimuli using semantic relationships, while there will be longer response times in performing the test for incongruent condition (condition 3) due to conflicts in the visual cues or stimuli as a result of Stroop inhibition from having semantic or verbal association compete with the task of identifying the sensory characteristics of the set of numbers, which in this case is the kind of digits represented or used in each set versus the number of digits written in each set (Windes, 1968). These conflicts happen as a result of the simultaneous activation of brain regions which causes working memory to interfere (Cohen, et al., 1990; Liotti, et al., 2000; MacLeod, 1991). As such, the rationale and the hypotheses for this study are as follows: Rationale: It is expected that response times (RT) in the numerical Stroop test under neutral (conditions 1 and 2) and congruent condition (condition 4) may have no observable differences, however the RT in condition 3 (incongruent conditions) is expected to be longer due to the presence of conflicts in visual cues. Null hypothesis: There are no significant differences between the mean length of RT in each set of numerical Stroop tests of reading and counting neutral or congruent number and letter sets. Alternative hypothesis: There are significant differences between the mean length of RT in each set of numerical Stroop tests of reading and counting neutral or congruent number and letter sets. Method Participant In this experiment, race or ethnic background, as well as the field of specialization were not used as indicators for selection, thus the participants come from various backgrounds and college departments. The subjects in this experiment consisted of individuals from X-University including myself (n=121) under the research methods class which meets on Fridays 3:00pm and with ages ranging from 15 to 47 years, with a mean age of 22.8 years. Samples per gender were: males=32; females=89. Participants were selected through volunteering, and while they do not get paid their participations count as class credit. Participants were treated in accordance with the “Ethical Principles of Psychologists and Code of Conduct” (American Psychological Association, 2010). Materials The numerical Stroop test aims to find out if the amount of response time (RT) in the four-condition numerical Stroop test (Conditions 1, 2, 3 and 4) differ significantly from each other. The materials used for this experiment consisted of four sheets of papers, each with a different kind of test or condition and consists of 32 items each. All subject responses were in oral form and recorded by the surveyor along with the speed of performing each test condition and errors detected, and as such it was important that every participant says their answer out loud so that the one administering the survey can properly record and time their responses. The first condition was reading the numbers per sequence set, for example reading the five-number sequence 3, 5, 1, 4, and 2 , the second condition involved counting the number of X’s per item, for example the letter set XXXXX has five X’s and the letter set XXX has three items and so forth, the third test was an incongruent condition which consisted of a mismatch between the written digits and the number of digits per item, for example the number set 8888 has four digits and the number set 33 has two digits and so forth, and the fourth condition was similar to the third test but is a congruent condition, wherein the number of digits match the written numbers per item, for example the number sequence 4444 has four digits and 7777777 has seven digits, and so on. The items in each test were randomized in a way that the sequences in each condition per test do not resemble one another. The numerical-type Stroop test given to the participants was adapted from the original experiment by Windes (1968). Procedure This study aims to find out if the results in each condition in the administered Stroop test will differ significantly with each other. The test used four conditions and was done in the following sequence: reading numbers (Condition 1); counting numbers (Condition 2); counting digits in an incongruent condition (Condition 3); and counting digits in a congruent condition (Condition 4). As such, the independent variable for this test were the administered four conditions in the Stroop test and the dependent variables were the mean response times (RT) recorded in seconds for each condition. Since the participants also belong to the same class, the test was done on their first meeting and that all of them were able to take the numerical Stroop test in the same day. The test was done by the participants in pairs in the classroom, with one performing the test while one records the response times and exchanging their roles after the test participant finishes the test. Reaction times were timed and recorded using cellphone timer settings, and the area is illuminated with sufficient but not excellent lighting. Because the test was done by each pair of participants at the same time there was too much audible interference to make it convenient for the participants, but it was still enough to get the necessary information. The following instruction was given to all paired subjects before the actual test session started: For the first test, the participant must read the digit in each of the 32-item number sequences as loudly and as quickly as they can with minimal to no errors. For the second test, the participants must count the number of X’s in each of the 32-item letter sets as loudly and as quickly as they can with minimal to no errors. For the third test which is the incongruent condition test, the participants must count the number of digits in each of the 32-item number sets as loudly and as quickly as they can with minimal to no errors. Lastly, for the fourth test or the congruent test, the participants must count the number of digits in each of the 32-item number sets as loudly and as quickly as they can with minimal to no errors. Subject-pairs reversed the order of examiner-participant after one finishes the test set, and test participation was recorded for proper class crediting. Results The results of the numerical Stroop experiment are as follows: The reading condition or Condition 1 (mean response time=11.1s/SD=1.9s); the counting condition or Condition 2 (mean=13.1s/SD=1.9s); the incongruent condition or Condition 3 (mean=18.1s/SD=3.4s); and the congruent condition or Condition 4 (mean=12.2s/SD=2.2s). These results are also tabulated and shown in Appendix 1. The results were obtained from a sample size of n=121, which consisted of males (n=32) and females (n=89). Values obtained from one-way ANOVA showed that at F(3,480)=201.4, p Read More