A variation of the Stroop effect experiment
An experiment to investigate the Stroop effect in which participants are asked to name the colour in which a word is written, that word having either a colour- association or a neutral association. ABSTRACT. This study was an investigation of the cognitive processes at work during a variation of the classic Stroop test and effect, in which the degree of intrusion into automatic thought processes may be witnessed in a colour identification task.
It was found that the rate of word identification was slower where the list contained words which had association with colour than when colour neutral words were being read thereby leading to inference that interruptions to unconscious somatic processing were taking place in the former condition. INTRODUCTION The Stroop effect is a well- established robust phenomenon which deals with the interruption to automatic thought processing by a certain task. Although first described by John Stroop in 1935 the experiment had been first carried out by scientists in Germany, (Jaensch, E. R. 1929).
A variation of the Stroop effect experiment Essay Example
The ‘effect’ refers to the amount of difficulty experienced by participants in excluding information, both sensory and learned , that conflicts with the task. It is also concerned with the prioritisation that takes place regarding one mental operation over another, (Broadbent,D. E. 1958), or how one operates to the detriment of another. The classic experiment uses colour words, i. e. red, green , blue etc. and has them printed in non -corresponding/incongruent coloured ink which participants are then asked to read out against the clock, times being recorded in each instance and also mistakes.
The first list of words, (condition 1), which they have previously read out are non- colour words which are also printed in the same coloured inks as the second list,( condition 2), and have no colour association whatsoever. The effect is noted when there is a significant difference/increase in the time taken to read out the list of colour words showing that the automatic process of reading, ( Reed. 1988), is being disrupted. The cause of the disruption is the recognition of the colour words and the colour ink confused by the fact that they are incongruent. There is therefore competition for conscious attention, ( Cherry.
E. C. 1953), and this slows down the ability to perform the task. The experiment pertaining to this particular report was a variation upon the classic Stroop experiment. The first list of words, condition 1, was carefully selected so as to have no colour association at all and was printed in the same colour inks in the same randomisation and numbers as the second list, the colour associated words . None of the colour associated words were printed in the associated colour. Given the results of previous research into the classic effect, (Siegrist, 1995,1997 ;Strauss,Allen, Jorgenson& Cramer2005.
), the one tailed hypothesis for this experiment was that, in this variation, there would be a slower response time in the colour associated list than for the control list but that the colour associated list response times in this experiment would be faster than if a colour word list had been used. So the main reason for this experiment was to find out the degree of interruption to automatic thought processes as the direct colour connection with words is weakened, i. e. words that represent actual colour are dropped in favour of words with a distinct but less absolute association with specific colours.
The null hypothesis was that any relationship between response times and lists would be down to chance. METHOD. DESIGN. This was a one tailed, within participant, repeated- measures hypothesis related study. It was expected that the response times for the colour-associated list of words would be higher than for the list which had no colour associations. The I/V,( Independent variable), was the colour of the inks used to print the words in both lists. The D/V, Dependant Variable, was the RT,( response time), for the performance of the task. The coloured ink used to print each list was randomised and sequential.
The RT was measured in seconds, to the nearest second. The participants had no contact with each other during the process, and the instructions and ‘researcher script’ for discussing this prior to start were identical. There was no researcher deception involved in the project as all participants were made aware of the aim of the project in broad terms and that they would be asked to read out lists of words with reaction times being recorded. MATERIALS. A stop watch was used to time the responses. A colour printer was needed to print out the lists.
There was a list of instructions and also an informed consent form provided for discussion with the researcher. Two lists of thirty words were provided for the actual test and for the pilot. The lists were printed in Arial 36 font on white matt A4 sheets of paper. One contained a list of colour neutral words and the other list was colour-associated words. On the back of one list was printed in the same font “Condition one” and on the other list, “Condition two”. There were six colours of ink used and the colours were randomly assigned to the words in sequence for both lists. PARTICIPANTS. Twenty participants were recruited in all.
Sixteen from the Open University, and four more locally. The raw data from the O. U. were sent for inclusion in the final results. There were 9 males and 11 females between the ages of 18 and 68. All participants were subject to a preliminary interview/screening in order to address such extraneous variables as sight, hearing and speech problems that may have impacted on the outcomes. The ability to understand and co-operate with the process was also addressed at this point. Researchers sought and obtained informed consent from participants and the forms were signed and collected for safe- keeping with other confidential materials.
Ethical issues were also discussed at this time with each participant and they all confirmed that they were aware of their right to withdraw from the project at any point without having to give reasons as well as being entitled to skilled debriefing and support from identified confidential sources if required. Confidentiality regarding the information to be gathered and its storage and disposal was discussed with participants as too was Privacy, which in this case meant the amount of personal control over information they had and the flow of information between researchers. PROCEDURE.
Participants were provided with a desk and seat in a quiet and well lit room with the lists turned over on the desk top. They were re-informed of their right to withdraw at any point and were provided with the informed consent form which was discussed with the researcher and the list of instructions for the test was also provided and discussed at this time, whilst working through the example/pilot in order to familiarise each participant with the task . The demographic information was requested and noted for the relevant form. The instructions were read out to them and given to them.
The participant was ‘counted in’ using the stop watch and turned over ‘condition one’ list on zero. The list having been read, the response time to the nearest second was recorded. The procedure was repeated for the list labelled ‘condition two’. The order of list presentation was reversed for each alternate participant, i. e. list 1 followed by 2 , and then list 2 followed by 1, and back to 1 and 2. After the test the participants were invited to attend either a private or communal debrief session , (during which a Q and A session was to be encouraged), and were thanked at this time for their input.
It was reiterated that their data were confidential and that they could still choose to withdraw from the project even at this stage. RESULTS. Data were collated and tabled, see Figure 1, with attention to the mean response times . Researchers applied the t test,(paired samples ), to the collected data using SPSS 20,( see appendix 4),and obtained a t value of 4. 262, a d value of 19 and a p value-probability of 0. 000. This meant that there was a high statistical significance in the results showing that Reaction Times were unlikely to have occurred due to chance.
This also meant that it was possible to reject the Null Hypothesis at this stage. Figure 1. CONDITION. MEAN RESPONSE TIME-IN SECONDS STANDARD DEVIATION. Condition 1. (Colour related words). Time (seconds). 26. 40 6. 660 Condition 2. (Neutral words). Time (seconds). 22. 95 5. 987 DISCUSSION. The results of the experiment show that it took longer for participants to respond when reading out the list composed of colour-associated words printed in incongruent coloured inks than for reading out the neutral association list also printed in the various coloured inks.
This means that there was a definite and marked interruption to the automatic process of reading to such a degree that the task was impeded. It was therefore possible to rule out that the results had occurred by chance and rule out the Null Hypothesis. It was noted that there was a 10% anomaly in the raw data in that two of the participants appear to have read out the colour associated –list faster than they did the neutral list. The rest of the data supported expectations based upon results from previous research in this area,(Stroop, J.
R. 1935). The anomalous data were amongst those received from the Open University rather than from those collected locally therefore it is not possible for any contributing variables to be investigated at this point by this researcher. Conjecture might suggest the presence of practise effect or that the two participants may have been adept at one of the forms of speed/skim reading that concentrate less upon specific words and more upon overall content and meaning, (University of Cambridge 2012).
In evaluating this particular experiment it shows that it is of the highest necessity for a researcher to be involved at all stages of their research from the recruitment phase onwards. Without this it is virtually impossible to address such things as anomaly with any credibility, or for them to draw meaningful conclusions about the validity of any results. Although the results of this study show a marked difference in the times taken to read the two lists it is worth noting that a higher number of participants would need to be involved if there was to be a serious attempt at generalisation from the results.
The classic Stroop experiment has been adapted and evolved for use in the investigation of subtler areas of attention and cognition interruption e. g. exploration of the role of emotions in the automatic mental processes, (Cothran, R. D. Larson, R. 2008. ). There has also been more recent research into methods of carrying out stroop- testing , (Chafetz,M. D. Matthews, L. H. 2004), where Neuropsychological techniques are used to test and to gather results. It is held that these methods gather more accurate results and are also able to indicate the parts of the brain at work during the task and therefore enhance the usefulness of the
study A pertinent and practical application for further use of the stroop- test template as a means to research interruption to automatic somatic thought processes would be one that addresses the topical issue of whether someone driving a moving vehicle has their performance impaired by also trying to hold a telephone conversation at same time. Used in conjunction with Neuropsychological technologies, it may be possible to investigate exactly which part of the brain is dealing with which task and how priority of functioning is attained .