Hypothesis
Research Aim:
The aim of the study is to find out if there is a significant difference in the two separate lists of words in the Stroop Task.
Experimental hypothesis
It will take participants longer to read the word list where the colour of the ink and the word do not match, compared to the other condition where the words do match the colour.
Null hypothesis:
There will be no difference between the times taken for the participants reading the word lists if the ink and word do or do not match.
Independent variable:
The manipulation of two different lists of words: the normal condition of the words printed in the matching colour and the other condition where the colours and words conflicted.
Dependent Variable:
The time taken for the participant to read each set list of words.
Methodology
Experimental method:
Laboratory experiment. This method was chosen because it was advantageous in producing quantitative data to be analysed usefully.
Experimental design:
Repeated measures to avoid individual differences.
Materials:
To carry out the experiment the following materials were used:
- The normal list of words (appendix iv)
- The conflicting list of words (appendix v)
- Stopwatch
- Standardised instructions (appendix iii)
- Debriefing note (appendix ii)
Sample and Sampling methods:
Ten participants, five male and five female students. Age range was between 17 to 19 years old and was an opportunity sample, chosen so the experiment was open to anyone available and willing to take part in the college.
Procedure:
Participants were read standardised instructions. They were then given the first list of words (normal- colours matched to words) face down. The participants were then told to turn over the sheet and they were timed as they read out the first list. The time was then recorded. The sheet was then taken away and the same was done again with the conflicting list of words accordingly. The participants were then fully debriefed.
Controls:
The variables that I could control were firstly how I showed the participants the experimental materials. I did this by placing the lists face down, and the participants were then told when to turn them over. This was to avoid an increase in efficiency at reading the words, especially where the conflicting list was concerned. I made sure that each participant was given the non- conflicting list first and then the conflicting list, to make sure the variable was not extraneous and the results therefore turn out to be confounding. Even though the sampling method was opportunity, I made sure there was an equal number of a male and female selection to avoid gender bias.
Ethics:
There were no ethical flaws in the experiment as all participants were over 16 years old and were fully debriefed after the experiment. They were also given the choice to withdraw from the experiment at any time.
Results
As the table below shows, it takes significantly longer for a person to read out a conflicting coloured list of words after they have read out a normal list, where the colours match the words. The evidence I have presented also supports theories discussed in background information. For example, the ‘automaticity’ theory is supported because after the participants had read out the normal list of words, they continually confused the words with the actual colour because their attention had became used to reading out words with the colours matching.
Table A- Average time taken for participants to read out lists.
Range of normal list of words= 7.41 seconds
Range of conflicted list of words= 65.24 seconds
The mean difference between the means of the two conditions is 57.27 seconds; this was how much longer it took the conflicting list to be read out. The longest time it took to read in the conflicting condition was 132.22 seconds, mainly because the participant took a lengthy pause and commented on how difficult the task was!
The difference between the ranges in the two conditions shows that in the conflicting condition it was much harder to read correctly, as the longer range shows.
Statistical Analysis
A Wilcoxon test was applied to the set of results since the design was related and it was ordinal for significance and was a one- tailed test because I was recording the difference and I predicted the conflicting condition would be greater.
The analysis gave a result of T=0, and the degrees of freedom were 10(N=10). The critical value was T=0, giving a very high significance level of p <0.001, where an acceptable level is p<0.05. Therefore the experimental hypothesis can be accepted and the null hypothesis rejected.
Discussion
My results fully support the experimental hypothesis and reject the null hypothesis, that there is a very significant difference between the two conditions and that it takes longer for the participant to read the conflicting list of words, due to the interference of attention to the colours. I obtained results that all round expressed what previous research had obtained, and with a probability of less than 0.001, my results were very significant and the independent variable affected the time it took to identify the colour the lists were printed in.
Although the sample size was small compared to the general population there was strong support that the Stroop Effect occurs within our attention. If I was to conduct the experiment again, I would like to use a bigger sample over a broader range of background, for example, it would be interesting to compare people’s I.Q to how long it would take them to read conflicting words, and then compare these two variables to see if intelligence might affect this process. Instead of an opportunity sample, I could use a stratified sample to find out about this.
It was basic to control all the important variables, such as handing out the standardised instructions, and word lists out face down so the results could not be extraneous, meaning the participant could not see the words beforehand to prepare what they would say out, especially where the conflicting words were concerned. However my experimental design was repeated measures and although advantageous in controlling for individual differences, there could be a problem of order effects. Some flaws such as background noise could have affected the participant’s concentration, which might have took them longer in some instances to read out the words. I made sure that the experiment was not andocentric, and chose equal numbers of gender. However, the sample’s age range only reflected 17-19 year olds and if I were to redo the experiment, I would try to see if the same results occur in older people.
In the procedure, the participants read out three lists of non-conflicting coloured words continuously, and then were then told to read the conflicting list of words, almost immediately after. I thought this would be the most effective procedure because when the participant had finished reading the normal list of words, their attention was used to reading these non-conflicting words, and therefore they would find it more difficult to read the conflicting words, as their attention had become vulnerable to automatic processing, as commented on in my background. This however could have produced practice effects and if I were to improve on the experiment I would use counter-balancing to control for this, by giving half of the participants non-conflicting word lists and then conflicting word lists. The other half of the sample would do this the other way round and so if there were any order effects, it would affect both conditions equally.
Finally, in real life situation this theory could be applied to people with attention problems and revision, for example, people trying to study could associate different revision points with different colours, for example one branch in a mind-map could be a certain colour and then remembering this in an exam.
Appendices
(I)
Raw Data
The table below shows how long the participants took to read the two different lists of words, and the differences between the two conditions are seen clearly in the time gap.
Bibliography
- Brain,Christine. Advanced Subsidary Psychology- Approaches and Methods. (2000) Nelson Thornes Ltd, Delta Place,27 Bath Road, Cheltenham.
- Gross, Richard. Psychology a new introduction for A level Second Edition. (1998) Hodder & Stoughton, 338 Euston Road, London. NW1 3BH.
- Maglennon, Keith. Essential Practical Psychology. (1993) Collins Educational Ltd, 77-85 Fulham Palace Road, Hammersmith, London, W6 8JB.
-
Zimbardo, Philip. Psychology and Life. (1992) HarperCollins Publishers Inc. 10 East Street 53rd Street, New York.
References
- Craik. Lockhart(1973) Advanced Subsidary Psychology- approaches and methods. Page 26
- Flowers et Al. (1979) Psychology a New Introduction for A level Second Edition. Page 222-223.
- Gleitman (1981) Essential Practical Psychology. Page 108
- Shiffrin and Schnieder (1977) Psychology and Life. Page 227
- Stroop,J.(1935) Psychology a New Introduction for A level Second Edition. Page 222-223.
Contents:
Abstract - 1
Background- 2
Hypotheses-3
Methodology- 4 -5
Results-6
Discussion-7
Bibliography and References -8
Appendix I - Raw Data - 9
Appendix ii- debriefing note - 10
Appendix iii – standardised instructions -11
Appendix iv – example of conflicting words list -12
Appendix v- example of non- conflicting words list – 13
Appendix vi – statistical analysis of results and other data -14
