Memory Schemas, Source Monitoring & Eyewitness Memory

Transcription

1 Memory Schemas, Source Monitoring & Eyewitness Memory Psychology 355: Cognitive Psychology Instructor: John Miyamoto 05/09/2018: Lecture 07-3 Note: This Powerpoint presentation may contain macros that I wrote to help me create the slides. The macros aren t needed to view the slides. You can disable or delete the macros without any change to the presentation.

2 Outline Finish: Flashbulb memories Memory schemas Source monitoring Eyewitness memory Lecture probably ends here Psych 355, Miyamoto, Spr '18 2

3 Psych 355, Miyamoto, Spr '18 Summary of Results Depicted in these Graphs (Redundant) 3 Goldstein Fig Talarico & Rubin (2003) Number of details correctly recalled for everyday & flashbulb memories as a function of days after the event. Confidence in the accuracy of everyday & flashbulb memories as a function of days after the event.

4 Talarico Fig 1a Figure 1 from Talarico, J. M., & Rubin, D. C. (2003). Confidence, not consistency, characterizes flashbulb memories. Psychological Science, 14, Number of correct details diminishes over time for both flashbulb and everyday memories. Belief in the accuracy of memories diminishes over time for everyday memories but remains high for FBM's. Why Does Confidence Remains High While Accuracy Diminishes Over Time? Psych 355, Miyamoto, Spr '18 4

5 Why do people have high confidence in the accuracy of FBM's even though the accuracy declines? Psych 355, Miyamoto, Spr '18 5 Return to Question: Is there a Special Mechanism for FBM's? People keep thinking about flashbulb memories. Increases strength of memory. Supports the narrative rehearsal hypothesis. People add information that helps them make sense out of the memory, but the added information may not be accurate. The added information makes the memory more meaningful. Memory is constructive or reconstructive. Source misattribution. I.e., people learn something after an event but they come to believe that they learned it while experiencing the event.

6 Do Flashbulb Memories (FBM s) Involve Special Cognitive Mechanisms? Bottom line: No convincing evidence that FBM's involve special mechanisms, although there are ways in which they tend to be unusual. Encoding is often associated with stronger emotion, more vivid detail, events are more personally important. It is likely that FBM s are retrieved multiple times. These retrievals lead to strengthened associations with other facts and ideas. Consolidation and reconstruction of memory over time. Over time, people have higher confidence in the accuracy of FBM's than everyday memories from the same time period. FBM's appear more vivid and more clear at time of retrieval. Psych 355, Miyamoto, Spr '18 6 A Schema for "Office Rooms"

7 Psych 355, Miyamoto, Spr '18 7 Predictions & Findings of "Office Room" Experiment Brewer & Treyens (1981) : A Schema for "Office Room" Schemas: Representations of typical characteristics of objects, situations or events. Subject asked to wait in this office room for about 30 seconds prior to start of experiment. Subject does not know that memory will be tested for this room. Subject is moved to another room. Recall test What do you remember about the waiting room?

8 Brewer & Treyens (1981): A Schema for "Office Room" Predictions: Memory will be biased... (a)... towards recall of schemaconsistent information; (b)... and against recall of schemainconsistent information Findings: Correct recall: Desk, chairs, shelves Intrusion Errors: Books on shelves Omission Errors: Skull, small doll Schema consistent Schema inconsistent Psych 355, Miyamoto, Spr '18 Advantages & Disadvantages of Schematic Influences on Memory 8

9 Psych 355, Miyamoto, Spr '18 Roediger/McDermott/Deese Experiment Same as Coglab 9 Schemas and Scripts Influence Memory Memory can include information not actually experienced but inferred because it is expected and consistent with the schema "Scripts" are like schemas except that a script is a typical sequence of events or actions. We have scripts for how to pay for our purchases in a check out line at the market. We have scripts for how to greet a respected visitor to our home. Memory is constructive. The constructive property of memory is generally advantageous, but it can lead to errors or false memories

10 Psych 355, Miyamoto, Spr '18 10 Instructions for the Experiment False Memory 1 Downloaded with permission from Thomas Pusateri s website, 29 December The version of the demonstration shown here slightly modifies the original. Demonstration of the Deese (1959), Roediger & McDermott (1995) false memory paradigm.

11 Roediger/McDermott/Deese Paradigm You will see a list of 19 words, one at a time. Do whatever you can to remember as many words as you can. At the end of the list, write down as many of the words as you can recall. Note to Instructor: The following stimulus slides are self timed (1.8 seconds/slide), so just let them run. You don t have to advance the slides. Psych 355, Miyamoto, Spr '18 11 Start of the Stimulus Sequence

12 BED Psych 355, Miyamoto, Spr '18 12

13 CLOCK Psych 355, Miyamoto, Spr '18 13

14 DREAM Psych 355, Miyamoto, Spr '18 14

15 NIGHT Psych 355, Miyamoto, Spr '18 15

16 TURN Psych 355, Miyamoto, Spr '18 16

17 MATTRESS Psych 355, Miyamoto, Spr '18 17

18 SNOOZE Psych 355, Miyamoto, Spr '18 18

19 NOD Psych 355, Miyamoto, Spr '18 19

20 TIRED Psych 355, Miyamoto, Spr '18 20

21 NIGHT Psych 355, Miyamoto, Spr '18 21

22 STOVE Psych 355, Miyamoto, Spr '18 22

23 INSOMNIA Psych 355, Miyamoto, Spr '18 23

24 REST Psych 355, Miyamoto, Spr '18 24

25 TOSS Psych 355, Miyamoto, Spr '18 25

26 NIGHT Psych 355, Miyamoto, Spr '18 26

27 ALARM Psych 355, Miyamoto, Spr '18 27

28 NAP Psych 355, Miyamoto, Spr '18 28

29 SNORE Psych 355, Miyamoto, Spr '18 29

30 PILLOW Psych 355, Miyamoto, Spr '18 30

31 ************************************************ WRITE DOWN THE WORDS YOU SAW ************************************************ Actually you can skip this step, but this is what subjects are asked to do. Correct List of Words & Types of Erors Psych 355, Miyamoto, Spr '18 31

32 Here are the stimulus words in the presented order: BED, CLOCK, DREAM, NIGHT, TURN, MATTRESS, SNOOZE, NOD, TIRED, NIGHT, STOVE, INSOMNIA, REST, TOSS, NIGHT, ALARM, NAP, SNORE, PILLOW Types of Memory Errors Intrusion errors: Words not on the list that you thought were there. o Common intrusion error: Sleep related words like: SLEEP, DROWSY or FATIGUE Omission errors: Words on the list that you didn't recall. o Common omission error: Non-sleep related word like: STOVE Psych 355, Miyamoto, Spr '18 Interpretation of Experimental Results 32

33 Psych 355, Miyamoto, Spr '18 33 Advantages & Disadvantages of Memory Schemas Interpretation of Results for the Roediger/McDermott/Deese Paradigm Almost all of the words are sleep-related ("going to sleep" schema). The Roediger/McDermott/Deese paradigm is designed to cause subjects to make two kinds of errors: (a) Schema-consistent intrusion errors. In the preceding example, the schema was something like "objects or actions that are related to sleeping." For this example, schema-consistent intrusion errors would be words like: "sleep", "drowsy", "pajamas", etc. (b) Schema-inconsistent omission errors. The word STOVE was the only non-sleep related word in the list. Subjects are more likely to omit STOVE than other words.

34 Constructive Memory Advantages Helps to create a meaningful narrative about our life experiences. Allows us to fill in the gaps in our knowledge. Speeds up how quickly we can interpret or respond to a situation. Schemas help organize experiences into "chunks" that are easier to manipulate in working memory, and easier to associate with similar experiences. Disadvantages Sometimes our memories are based on expectations and not on the actual experience. Sometimes we make errors without realizing it. Intro to Eyewitness Testimony 34

35 Eyewitness Testimony Basic source of evidence in the Anglo-American legal system. Historically more trusted than circumstantial evidence. Of 341 people who were exonerated by DNA evidence as of 2012, eyewitness testimony played a role in 75% of the original convictions. (Quinlivan et al., 2009; Scheck et al., 2000). Sources of Error in Eyewitness Testimony Psych 355, Miyamoto, Spr '18 35

36 Source Monitoring & Source Misattribution Source monitoring - Retaining a memory of the source of a memory. What was the source of this memory? Source misattribution - attributing a memory to one source when the actual source was something else. Example: My friends tell me about a large building fire that they witnessed. Years later I believe that I witnessed this fire along with my friends. Source Misattribution & Errors in Eyewitness Memory Psych 355, Miyamoto, Spr '18 36

37 Source Misattribution is One Cause of Erroneous Eyewitness Memory Source misattribution can cause errors in eyewitness testimony. A familiar face is more likely to be falsely identified as a perpetrator of a crime (witness thinks the familiarity is due to seeing this person commit the crime). Example: A woman was attacked in her home shortly after watching a TV show in which a psychologist, David Thompson, was interviewed. Later she identified David Thompson as the attacker. (He had an alibi, the interview on the TV show.) Remember/Know Distinction: Feeling of familiarity Recollection but people may say that they "remember" Mr. X when Mr. X is familiar. Ross et al. Experimental Study of Source Misattribution Psych 355, Miyamoto, Spr '18 37

38 Source Misattribution & Eyewitness Identification See Figure 8.17 in Goldstein Robber Not Present Experimental View male teacher reading to students Try to pick robber from photospread; male teacher present Control View female teacher reading to students Both Conditions View female teacher getting robbed by a man. Robber Present Try to pick robber from photospread; male teacher present Ross, D. F., Ceci, S. J., Dunning, D., & Toglia, M. P. (1994). Unconscious transference and mistaken identity: When a witness misidentifies a familiar but innocent person. Journal of Applied Psychology, 79, Same Slide with Emphasis Rectangles Psych 355, Miyamoto, Spr '18 38

39 Source Misattribution & Eyewitness Identification See Figure 8.17 in Goldstein Robber Not Present Experimental View male teacher reading to students Try to pick robber from photospread; male teacher present Control View female teacher reading to students Both Conditions View female teacher getting robbed by a man. Robber Present Try to pick robber from photospread; male teacher present Ross, D. F., Ceci, S. J., Dunning, D., & Toglia, M. P. (1994). Unconscious transference and mistaken identity: When a witness misidentifies a familiar but innocent person. Journal of Applied Psychology, 79, Experimental Results Psych 355, Miyamoto, Spr '18 39

40 % Identification of Male Teacher % Identification of Male Teacher Results of Ross et al. (1994) Figure 8.20: Ross et. al. (1994) 60% id male teacher when robber not in photospread. 20% id teacher in control group. 18% id male teacher when robber in photospread. 10% id teacher in control group. Source misattributions can cause mistaken identifications E C E C Robber not in photospread Robber in photospread E = Experimental Condition = View male teacher at stage 1 C = Control Condition = View female teacher at stage 1 Misinformation Effect Psych 355, Miyamoto, Spr '18 40

41 Overview of the Misinformation Effect MPI = Misleading Postevent Information Subject sees a video, or a slide sequence, or reads a story. I'll call this "the video." The video usually depicts a crime. After seeing the video, the subject is asked questions about it. For some subjects, the questions contain misinformation (a.k.a. MPI or false assumptions). Subjects receive a memory test. A misinformation effect is found if subjects who heard the misleading questions remember the video in a way that is consistent with the question and not the video. Introduce Loftus & Palmer - Car Crash Psych 355, Miyamoto, Spr '18 41

42 Psych 355, Miyamoto, Spr '18 42 Results: Effect of the Biased Questions MPI: Leading Questions Can Produce Memory Biases Loftus & Palmer (1974) Subjects see film of an auto accident. Questions contained alternative descriptions of the accident.

43 Leading Question Can Produce Memory Biases Verb Estimated Speed smashed 40.8 collided 39.3 bumped 38.1 hit 34.0 contacted 31.8 Loftus & Palmer Result for Broken Glass Psych 355, Miyamoto, Spr '18 43

44 Leading Questions Can Produce False Inferences One week later, subjects were asked: Did you see any broken glass? Actually, there was no broken glass in the film. Yes No "smashed" "hit" control* * The control group were not asked about the speed of the car (no misinformation; no correct information). Feedback Can Increase Confidence in Erroneous Memories UW: Psych 355, Miyamoto, Win '12 44

45 Psych 355, Miyamoto, Spr '18 45 Line Ups versus Show Ups Feedback Can Increase Confidence in Erroneous Memories Subjects viewed video of crime. Subjects shown a photo array that did not contain the perpetrator of the crime. All subjects picked someone from the photo array. (!!!) Confirming Feedback Condition: "Good, you identified the suspect." No Feedback Condition Disconfirming Feedback Condition: "Actually the suspect was number." Later when asked how confident they were in their identifications, subjects were most confident with confirming feedback.

46 Wednesday, 9 May, 2018: The Lecture Ended Here Psych 355, Miyamoto, Spr '18 46

47 Lineups versus Show-Ups What Are They? Classic showup: Police show only one person to a witness, often somebody who was caught near the scene of the crime. Question: "Is he the man you saw?" Classic lineup: Police show 7 people to the witness: Question: "Do you see the perpetrator in the line up?" Improved showup = sequential showup: Police tell the witness, "We're going to show you a series of men (of unstated length). Stop me when you see the perpetrator." Contrary to most people's expectations, show ups are more accurate than line ups. Why are showups more accurate than lineups? Why Lineups & Showups Differ as Cognitive Tasks Psych 355, Miyamoto, Spr '18 47

48 Cognitive Differences Between Lineups and Showups Classic showup: Witness asks himself/herself: "Did I see this person do the crime?" Classic lineup: Witness assumes that the perpetrator is in the lineup. Witness asks himself/herself: "Which of these men looks the most like the person that I saw?" Sequential presentation = sequential showup (Goldstein refers to this a sequential presentation) With each person, the witness asks himself/herself: "Am I sure that this is the person who I saw do the crime?" Mistake! Mistake! Lindsey & Wells (1985) found that the sequential showup greatly reduced false id when the perpetrator was not present (43% vs 17%) Sequential showups slightly reduced the rate of true id when perpetrator is present. Recommendations for Improving Eyewitness Memory - END Psych 355, Miyamoto, Spr '18 48

49 Recommendations for Improving Eyewitness Memory Use a sequential showup (Goldstein would call it a sequential presentation). In a showup, use non-suspects who are similar to a suspect. Inform witness that the perpetrator may not be in a showup. Administrator of showup should not know who is the suspect. Get confidence rating immediately after the initial identification. Avoid giving feedback to the witness after the lineup Use cognitive interview techniques; do not prompt the witness with leading questions. See Wikipedia article on cognitive interview techniques: Psych 355, Miyamoto, Spr '18 49 END