1. The Psychology of Illusory Memories : Introduction to its basic notions
David Kellen

2. Hallo!
My name is David Kellen, and I’m a PhD student at the Social Psychology and Methodology Department.
Me and Henrik are friends, colleagues, and partners-in-crime.
My work focuses on the development and testing of mathematical measurement models in the field of recognition memory.
That’s not what I am here to talk about.

3. Hallo!
What brings me here is the topic which originally made me go into research: Illusions of memory
I think it is a pretty interesting phenomenon for several reasons:
It occurs in many different ways
It presence goes back to the foundations of this field
It is very polemical (at least outside Academia)
Has practical implications

4. Lets start from the beginning…
Scientific research in the field
of memory can be traced
back to the work of
Ebbinghaus (1885) on forgetting.
Basically the experimental procedure of Ebbinghaus (which we conducted on himself) consisted in the memorization of lists of non-sense syllables to the point of perfect memorization (being able to repeat it without errors).

5. Lets start from the beginning…
Afterwards, in predetermined periods of time, remembrance of list were made, and the responses recorded.

6. Lets start from the beginning…
The work of Ebbinghaus was not only important for what it was, but also for the scientific framework that it created, influencing the work of future generations of researchers.
The main idea that it conveys is one of memory as something which retains information, and that one should focus on how this information is retained and for how long.
So the focus was placed on correct remembering.

7. Lets start from the beginning…
Besides correct remembering, one could focus on what errors are made when attempting to remember something.
In this respect an important aspect to take into consideration is how we can make mistakes.

8. Lets start from the beginning…
Not remembering something that occurred
(omission error)
“Jamais-vu”
Remembering something that did not occur
(comission error)
“Déjà-vu”

9. Lets start from the beginning…
Focusing on omission errors and neglect comission errors made sense in the work of Ebbinghaus because the latter had no theoretical relevance.
(remember BIPO instead of LAPA?)
But these circumstances are the exception and not the rule, as we shall see…

10. Enter Bartlett The opposite focus was made by Sir Frederic Bartlett.
Although Bartlett was an “Experimental Psychologist”, he saw the field of memory intrinsically connected with Social Psychology.
One of the most important contributions of Bartlett was in the notion of “schemas” in reasoning and memory.

11. Enter Bartlett
In his 1932 book, entitled “Remembering”, Bartlett reported the very famous “War of the Ghosts Experiment”.
The experiment consisted in reading to the participants a short story comprised of simple phrases, all which conveyed a general “gist” of the story, and some that were incongruent with the rest of the story.
After several days, the partipants were asked to remember details of the story as better as they could.

12. Enter Bartlett
The results showed that participants tended to remember better details that are closely connected to the general structure of the story than details that were not congruent with it.
Also, it was observed that participants tended to remember details that were not present at all, but were consistent with the story, or to distort incongruent details into congruent ones.

13. “Memory as a reconstructive process”
Enter Bartlett
This results are consistent with Bartlett’s idea of “schema-based memory”.
Basically, that individuals have knowledge structures in which shape the way new information is interpreted and ultimately stored, and recovered.
When information is incomplete, it is reconstructed using these knowledge structures, which leads to the production of commission errors.
“Memory as a reconstructive process”

14. Enter Bartlett
The errors produced by the participants are extremely informative in the sense that they reflect the underlying knowledge structures.
These ideas spawned its own school of research, which was developed specially in the fields of Social Psychology and Social Cognition.
On contrary, in most memory research, the focus continued to be on correct memory responses.
But of course, “most research” does not mean “all research”…

15. Enter Deese
James Deese was a proeminent researcher in memory during the 40s and 50s.
In a very obscure paper (Deese 1959) studied the occurrence of “associative intrusions” in a free recall memory task.
In a previous study, Deese noticed that the intrusion errors were associated with words that were actually studied in the list (e.g. bed – blanket).

16. Enter Deese In his new study, Deese created special word lists.
These lists were constituted of words (bed, blanket, sheet, room, pillow) that are all associated to a non-included word (e.g., sleep).
When tested, the participants manifested a large proportion of intrusions, namely the non-included words, in some cases as much as 70%.

17. Enter Deese
This work of Deese was basically ignored during decades, only being brought up as a classroom-example of a cool memory effect.
This basically happened until 1995.
But we will talk about that later.

18. Loftus and Eyewitness Testimony
In the late 60s, Elizabeth Loftus was
a graduate student looking for a topic.
One of her ideas was to work on the effect of persuasion/misinformation on memory for specific episodes. During this time, this was considered to be a very unlikely effect.

19. Loftus and Eyewitness Testimony

20. Loftus and Eyewitness Testimony

21. Loftus and Eyewitness Testimony
For nearly two decades, several studies were published that supported a high degree of memory distortion.
Participants recalled things as different as:
nonexistent broken glass
Objects like tape recorders or suitcases
a cleanshaven man as having a mustache,
straight hair as curly
a barn in a scene that contained no buildings at all

22. Loftus and Eyewitness Testimony
These studies captured immense media attention given its importance in Legal cases, and even led to Death threats to researchers.
What the results suggested was that information can be implanted in someone’s mind, even in unintended, leading to the formation of false memories.
This raises several problems with some Clinical approaches such as Psychoanalysis, in which there is the belief in “repressed memories”.

23. Loftus and Eyewitness Testimony
The following questions should be posed:
Should the therapist be empathic, offering comprehension and support, or should he also question to a certain extent the truth of the memories/allegation of the patient?
To what extent a therapist can influence the memories of his patients?
In 1997, more than 800 lawsuits were made against therapists for planting false memories in their patients...

24. What happened to Bartlett??
The ideas of Bartlett were developed during the 70s in the subfield of “text comprehension”, leading to very interesting experiments.
One of such studies was reported by Bransford and Franks (1972), in which the effect of logical inferences in memory was examined:

25. What happened to Bartlett??
Presentation of sentences:
The ants were in the kitchen.
The cookies were on the table.
The ants ate the cookies.
.....
Recognition task with congruent distractors:
The ants were on the table.

26. What happened to Bartlett??
What the results showed was great proportion of errors, namely the recognition of logically congruent distractors.
This suggests a great difficulty in distinguishing between perceived information and inferred information.
“memory of an event VS. memory of a thought”

27. What happened to Bartlett??
This line of research was followed by
the work of Marcia K. Johnson.
A great deal of her work consisted in measuring participants’ abilities to accurately remember contextual information from the study phase.
This research amounted into a very important theoretical framework in memory – Source Monitoring.

28. What happened to Bartlett??
The main idea of the Source Monitoring framework is that information is not “tagged” in terms of its origin. Its origin has to bee inferred by the individual.
Keeping track of how or where you obtained specific information is a very important skill. One that we sometimes are not very good at.

29. What happened to Bartlett??
This logic is not limited to information “obtained from the outside”. Information that is produced internally (e.g.,thoughts, dreams, imagination, etc.) is intermixed with external information, meaning that individuals need to assess their origin as well.
The way information is assessed depends on several factors, like the motivation of the individual: In some circumstances, individuals might resort to fast heuristics, and in others to more systematic reasoning processes.

30. … and with good ol‘ Deese??
The work of Deese was “ressurrected”
by Henry Roediger and Kathleen
McDermott.
They updated Deese’s original experimental design, creating what is called the DRM (Deese-Roediger-McDermott) paradigm (Roediger & McDermott, 1995).

31. DRM paradigm
Participants first see a list of words, which are related to a non-presented word, called the “critical item”:

32. DRM paradigm
Afterward the presentation of each list, participants either recall the word lists, or do a distractor task.
After all lists were presented, participant engage in a recognition task.

33. DRM paradigm
The “DRM effect” has since been replicated in hundreds of studies. Very goods reviews can be found in Gallo (2006, 2010).
Some important findings:
The effect occurs even when participants are warned about its occurrence.
It increases if the interval between the study and test phases is larger.
The repetition of the lists leads to a reduction of the effect in young people but an increase in the elderly.

34. DRM paradigm More findings:
Participants tend to remember the critical item with great confidence, being able to report particular aspects of its occurrence.
The effect can even be obtained with subliminal presentation of the lists.

35. DRM paradigm So, whats the theory behind the DRM effect?
Actually it is pretty much a mish-mash from previous theories.
In general terms it considers that there are two main mechanisms :
Activation
Monitoring

36. DRM paradigm

37. DRM paradigm

38. DRM paradigm

39. Activation overload + Failure in monitoring
DRM paradigm
So the DRM false memories are produced by:
Activation overload + Failure in monitoring
Activation overload
Failure in monitoring

40. DRM paradigm Special populations that show a higher DRM effect
Individuals “kidnapped” by Aliens
(Clancy, McNally, Schacter, Lenzenweger & Pitman, 2002)
Women who report recovery of suppressed memories of abuse
(Clancy, Schacter, McNally, Pitman, 2000)
Individuals vulnerable to hypnosis
(Heaps & Nash, 1999)
Individuals that believe in extra-sensory-perception
(Rose & Blackmore, 2001)

41. To wrap things up
Fidelity of memory is unarguably an important and adaptive feature, so why are memories so fallible??
My 50cents?
Consider the main origin of the DRM paradigm, activation of an associative network.
Association – thats one of the most important abilities of the human being. One that makes us terribly smart.
The fallibility of human memory can be seen a cost for having such amazing ability.

42. To wrap things up
Of course we can always try to use our monitoring processes to distinguish what-is-what, but they are far from perfect, and they demand a lot of cognitive resources.
False memories are an intrinsic part of the human condition – the more you know about them the better.
thanks