Materials
All 4 lists consisted of 12 commonly used words in the English language, each list having its common concept (see Appendix B). A stopwatch was used to time the 3 seconds intervals between the presentations of each word and to allow 2 minutes for the recall of each list. A pen or pencil and 4 answer sheets (see Appendix C) were also provided to each participant.
Design
This experiment was an independent design experiment with equal number of men and women exposed to the two levels of the independent variable (forced recall instructions and free recall instructions). Counterbalancing against the order effect was also involved since each experimenter presented the 4 lists in different orders for the participants in each of the two experimental groups. The independent variable was the free recall or forced recall instructions given to the participants and the dependent variable was the number of false recalls and correct recalls obtained.
Procedure
All participants were tested individually. The following was said to each participant exposed to the free recall condition: “I will read 4 lists of 12 words each to you. After each list, you will be given 2 minutes to write down as many words as you can remember. There will be a 3 seconds interval following the presentations of each word.” Similarly, the following was said to the participants in the forced retrieval condition: “I will read 4 lists of 12 words each to you. After each list, you will be given 2 minutes to fill in all the spaces on the answer sheet. There will be a 3 seconds interval following the presentations of each word.” Each group followed their respective instructions as mentioned. A stopwatch was used to measure the 3 seconds interval between the presentations of each word and to make sure the participant was allowed 2 minutes to recall each list.
Results
The numbers of intrusions, central concept false recalls as well as correct recalls were calculated for each participants. Of a total of 4 lists of 12 words, the mean numbers of intrusions and central concept false recalls are 2.2 and 0.75 respectively for the free recall condition. For the forced recall condition, the mean number of intrusions is 9.2 and of central concept intrusions is 1.5. These results clearly show that there is more total false recalls for participants who were given the forced recall instructions than for those who were given the free recall instructions (10.7 > 2.8).
Furthermore, the mean number of correct recalls for the free retrieval condition and the forced retrieval condition are 34.6 and 37.3 respectively. This illustrates a slightly higher correct recall for forced recall condition than for the free recall condition. From a more general conclusion however, correct recall is relatively constant for both conditions.
Results for Free Retrieval Condition Group Results for Forced Retrieval Condition Group
Discussion
This experiment hypothesised that false recall will be greater under forced recall instructions than under free recall instructions whereas correct recall will stay unaffected. The first part of our hypothesis complied with our results since they clearly show higher false recalls (either intrusions or central concept false recalls) in the forced retrieval condition than in the free retrieval condition. This finding is consistent with Stuart’s study (2001) and can be deduced and explained sensibly as follow. Participants under forced retrieval instructions were compelled to make repeated attempts to recall all the 12 words of each list, which incited them to write down more intrusions and central concept false recalls. On the other hand, participants under the free recall instructions only had to recall what they could and were hence less likely to write down words that they were less certain of recalling.
However, the second part of our hypothesis was not as clearly confirmed by our results. Indeed, the mean number of correct recall for the forced retrieval condition is slightly greater than for the free retrieval condition (37.3 > 34.6). One possible explanation for this finding is that participants under the forced retrieval instructions had to put more effort in recalling the list of words and so succeeded in finding more correct recalls. Nevertheless, since our experiment did not involve as many participants as Stuart’s and the difference in the mean number of correct recalls is not greatly significant, we may estimate that if we had taken a larger sample of participants, we may have gotten the same results as Stuart. Namely, correct recall would remain unaffected whether in the forced or free retrieval condition. Hence, the results of the present study were generally consistent with those of the replicated study by Stuart (2001), and confirmed our initial hypothesis that false recall is higher under forced recall instructions and correct recall is unaffected.
There is no significant difference in the results obtained between the lists so we may reason that all 4 lists were composed of relatively common English words of equal difficulty. In addition, while the mean numbers of central concept false recalls are similar for males and females under the forced recall condition, central concept false recall is significantly greater for males (1.3 • 0.25) in the free recall condition. Once again, since this experiment involved only 32 participants, this difference is not yet conclusive. It would be interesting for future experiments to investigate this matter further.
Moreover, our results are also grounds for other interesting observations. First, many particular words were repeatedly misspelled because of their similar pronunciation with another word. For example, “brake” was mistakenly written as “break” 7 times, “slippers” as “sleepers” also 7 times, and “litter” as “leather” 3 times. This is due to the fact that the participants perceived the words through their auditory sense since they were read to them. Many false recalls that were not the central concept but were still in the theme of the list also recurred. For example, “wheel” appeared 7 times in the list with the central concept “car”. This illustrates how one may organize information into our memory by semantic groupings. Additionally, one participant under the forced recall condition, while trying to recall a particular word, reported that she had it on the “tip of her tongue”. She knew its meaning and seemed to have a vague image of its syllables but she just could not recall it. This TOT state (tip-of-the-tongue) shows that information is organized also in the terms of the way words sound or look.
The results of the present experiment demonstrate that every word whether at the beginning, the middle, or the end of the list, was recalled as often as another one. Hence, the serial-position effect could not be observed here. However, I suspect that this is due to lists being rather short. I believe that with longer lists, this effect will be shown. As well, the present study only tested for echoic memory since the participant perceived the words as auditory stimuli. It would be interesting to see if the same results will be obtained if the presentation of each word was done by showing a cue card on which that word will be written. Will false recall be also greater under forced recall instructions than under free recall instructions?
Bibliography
MacLin, M. & Solso, R. (2002). Experimental Psychology: A Case Approach. Boston: Allyn and Bacon.
Stuart, J. (2001). Effects of free and forced retrieval instructions on false recall and recognition. The Journal of General Psychology,Vol.128, Iss.3.
Tavris, C. & Wade, C. (2001). Psychology in Perspective. New Jersey: Prentice Hall.
Appendix A
Consent Form of Memory Recall Experiment
My name is Hau Nguyen. I am an International Baccalaureate Science student performing a research for partial credit in an experimental Psychology course at Vanier College.
You are being asked to participate in a psychological experiment investigating memory. You will be given 4 lists of 12 words and asked to remember them. The entire experiment will take between 15 to 20 minutes. All personal data will be kept confidential, as your name will be coded. You may withdraw from the experiment at any time. Following the experiment, the results will be communicated to you by the first week of November.
If you have any questions please feel free to ask me or contact my supervisor Dr. Evangeline Caldwell at 514-744-7219 or at .
I, __________________________ ____________________________, understand that my
(First Name) (Last Name)
participation in this experiment is voluntary and that I may refuse to participate or withdraw from this experiment at any time.
_____________________________ ______________
(Participant’s signature) (Date)
_____________________________ ______________
(Parent’s signature if participant is under 18) (Date)
_____________________________ ______________
(Experimenter’s signature) (Date)
Appendix B
Appendix C
Participant’s Answer Sheet
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