1. Otgaar and colleagues looked at whether Prevalence information changes memory in any form when focusing on implausible events. The aim of the investigation was to see if children between the ages of 7-8 and 11-12 could create false memories when asked to recall an implausible or plausible event. The second aim also focused on whether the level of false memory recalled when levels of prevalence has been changed which was controlled by having a condition with no prevalence. Henry Otgaar himself says “Hence, my main research interest lies in the identification of mechanisms that contribute to the development of memory illusions” 1
2. The first stage involves making the individual believe that the specific event is plausible thus more believable. If the event is implausible it can be made plausible by combining with false evidence. This evidence is presented to the individual in order to increase the likelihood of the event occurring thus making it more acceptable and reliable. The second stage is to aid the participant into believing they could have experienced this event in their past. Lastly the final is stage where the participant actually produces a false memory of the event. This is because the actual thoughts were confused for memories instead of fantasies. Evidence for the two stages can be seen as the study says “Exposing people to a set of articles that describe a relatively implausible phenomenon, like witnessing possession, made people believe that the phenomenon is more plausible, and also made them less confident that they had not experienced the event in childhood….with effect sizes ranging as high as 2.42 standard deviations.”2Evidence shows that implausible events can be made believable and that there is an increase in perceived likelihood of an event occurring if the participant is provided with a credible source however it must be highlighted that only two of the three stages were supported in this research.
3. The true narrative was matched in terms of plausibility because each primary school child had experienced this event. The valence for the true narrative wasn’t directly matched as this would be subjective to the individual however the first day of school is a stage of life and therefore is standardised for everyone to an extent. The false narrative used a pilot study where children rated valence and plausibility using a smiley face chart. Script knowledge was tested by the same children but only 19 of them had to demonstrate everything they knew about the event. Two events were finally picked from the list as both the events choking on candy and being abducted by a UFO were similar in terms of Valence and script knowledge. The only differing event was the higher plausibility for choking on candy.
4. In the experiment there were three categories which the experimenter manipulated. This was the age where the child was young (7-8) or old (11-12).Secondly prevalence was looked at along with the implausibility or plausibility of the event. The children were randomly associated each of the four conditions; No prevalence, prevalence, implausible or plausible event. The prevalence condition used a fake newspaper article (UFO abduction) and also helped the child by prompting and retrieval techniques. The experimenter interviewed each child participant twice throughout the study at the start and end and also audiotaped and transcribed each one. During the interview the participant was presented with one true narrative and one false narrative and it was clear that the true aim was not given away in case it would cause desirability bias and affect results. Finally in interview 1 the children were told to remember the everyday events till their next interview and most importantly not discuss any of the events with their parents however in interview 2 the children were debriefed on false events and told true aims making sure not to break any ethical issues.
5. The independent variables consist of the prevalence of the event, whether the event was plausible or implausible and finally the ages of children used in the sample. The dependant variable is the number of children of both age groups who experienced false memories.
6. This study used unrelated design (3-explains unrelated design) because there were 2 different groups children associated with 4 different conditions. In this experiment there were two groups 7-8 and 11-12 children who were classified into one of the four categories; prevalence (fake article),no prevalence and Plausible(First day of school) or implausible(UFO abduction).
There are many advantages of this design. Firstly the aim could correctly be measured as the difference between conditions could be observed. Participants could only be used once therefore there is no order effects for example, fatigue and boredom. Participants are less likely to show demand characteristics and are less likely to guess the aim of the study. Lastly it is also the easiest and most convenient way of allocation participants as it is random and therefore less time consuming in turn all these aspects increases the external validity. However a disadvantage would be that as two different groups of participants are used it could be argued that the difference in results could be due to their individual differences. Extraneous factors like difference in IQ decreases the internal validity and overall reliability of the results obtained.
7. It was important that the true aims of the study were not revealed and so that they could distinguish factors between a true memory and a false memory. A true memory was also needed as a comparison and as a control variable.
8. If the participant couldn’t recall description of the implausible event they were aided with retrieval techniques & prompting by the experimenter. If the child couldn’t confidently recall the event as a memory they were classified as not having a false memory however if they gave more specific details of event they were classed as positively having a false memory.
9. A Laboratory experiment was used meaning there was a lack of mundane realism as the study was not conducted in a natural setting thus decreasing its ecological validity. An improvement could be to carry out the experiment in a natural setting instead of a formal interview environment which would increase the level of reality giving more ecologically valid results. A sample of children between the ages of 7-8 and 11-12 years therefore the results cannot be generalised to all primary school children. Another important point is that these results cannot be generalised to adults (prediction based on adult study on false prevalence information) as they were only tested on children. Repeating the test on a wider variety of age ranges including adults would increase its ecological validity. It could be argued that the observations of the number of false memories could have been biased as it was based on solely the decision of the experimenter.
The participants could have complied with the implausible event as they wanted to look good in front of the experimenter or were too shy to contradict them known as social desirability bias. This could be solved by observing the child in a covert manner. The description for a positive false memory depended on the quality of information represented by the child which was qualitative therefore raising issues on experimenter bias and experimenter effects. A solution can be to predict categories of actions which were required for an event to be described as a false memory and use this as a criterion when assessing a child’s description of the implausible event. More than one experimenter could have viewed the videotape of the child to decide whether a false memory was experienced to increase reliability.
10. Results from table 1 shows the 7-8 year categories has a higher number of children who experienced false memories for the implausible (UFO) event for both the prevalence and no prevalence scenarios in comparison to the children in 11-12 year group. In general the younger group experienced more false memories than the older children for both implausible and plausible events. In the 11-12 years category there is a higher frequency of children who experienced false memories in the plausible condition in comparison to the implausible condition. The most surprising result showed an increase in the second interview for both ages in the no prevalence, plausible event however there was a decrease in false memories for the prevalence, plausible event.