1 / 47

Flashbulb Memories, Memory Schemas, and Eyewitness Testimony

Flashbulb Memories, Memory Schemas, and Eyewitness Testimony. Psychology 355: Cognitive Psychology Instructor : John Miyamoto 05/13 /2014: Lecture 07-2.

breindel-dorsey
Download Presentation

Flashbulb Memories, Memory Schemas, and Eyewitness Testimony

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Flashbulb Memories, Memory Schemas, and Eyewitness Testimony Psychology 355: Cognitive PsychologyInstructor: John Miyamoto05/13/2014: Lecture 07-2 This Powerpoint presentation may contain macros that were used to create the slides. The macros aren’t needed to view the slides. If necessary, you can disable the macros without any change to the presentation.

  2. Outline • Flashbulb memories – Are they like ordinary memories?Are there ways in which they differ? • Memory schemas – templates for common experiences • Memory errors • Eyewitness testimony and source monitoring errors Lecture probably ends here # Psych 355, Miyamoto, Spr '14

  3. Flashbulb Memories (FBM's) • Hypothesis: Memory for the circumstances in which one learned about a dramatic or shocking event is preserved as if a photographic image was made by using a flashbulb with a camera. • Many people share very distinctive memories for major events. • Where were you and what were you doing when you first heard about the attack on the World Trade Center? • If you have ever been in a car accident, do you have memories of the very first car accident that you were in? • Are flashbulb memories different from regular memories?How do they change over time? • Do flashbulb memories involve different memory mechanisms from those that create or maintain ordinary memories? What Creates a Memory that Lasts a Long Time? Psych 355, Miyamoto, Spr '14

  4. What Creates Memories that Last a Long Time? • Elaborative rehearsal (connecting a memory to other knowledge) • Personal importance causes repeated retrievals of a memory. • Distinctiveness • Strong emotions enhance memory • Hamann, Ely, Grafton, & Kilts (1999): PET study. • Showed subject very pleasant, very unpleasant and neutral pictures. • Emotionally charged pictures produced stronger amygdala response, and better memory. • Cahill, Babinsky, Markowitsch, & McGaugh (1995). Patient with damaged amygdala (B. P.) had normal memory for unemotional narratives, but did not show enhanced memory for emotional parts of a narrative. • Distributed practice as opposed to massed practice Do FBM's Involve a Special Memory Mechanism? Psych 355, Miyamoto, Spr '14

  5. Is There A Special Memory Mechanism for Flashbulb Memories (FBMs)? Pro: Special Mechanism • FBMs are consequential – they have high impact on our lives. • FBMs often produce strong emotions. Con: Special Mechanism • Narrative rehearsal hypothesis – we think repeatedly about these events. They are only special because of this rehearsal. • Just because we have vivid memories for FBMs doesn't mean that the memories are accurate. Are FBM's Accurate? Psych 355, Miyamoto, Spr '14

  6. Accuracy of FBM's • Mixed evidence • Neisser & Harsch (1992)Subjects filled out a questionnaire within 1 day of Challenger disastor (1986), and a similar questionnaire 2.5 years later. • Subjects were asked how they learned about the disaster. • Large distortions. • Phantom flashbulbs – subjects often replaced initial memory with another, TV-based memory. • 21% said that they initially learned of event from the TV.After 2.5 years, 45% said that they learned of event from the TV. Time Course of Memories for 9/11 Attacks Psych 355, Miyamoto, Spr '14

  7. Talarico: Time Course of an FBM Talarico, J. M., & Rubin, D. C. (2003). Confidence, not consistency, characterizes flashbulb memories. Psychological Science, 14, 455-461. • Studied memories for the 9/11 attack on WTC. • On 9/12/01, 54 Duke students wrote down their memories of how they first heard of the 9/11 attack. They also wrote down a recent everyday memory, e.g., going to a sporting event. • The study compared 9/11 memories to everyday memories after varying delays. Graphs Showing Decrease in Accuracy but not Decrease in Certainty for FBM Psych 355, Miyamoto, Spr '14

  8. Talarico Fig 1a • Number of correct details diminishes over time for both flashbulb and everyday memories. • Over time, belief in the accuracy of memories diminishes more for everyday memories than for FBM's. Figure 1 from Talarico, J. M., & Rubin, D. C. (2003). Confidence, not consistency, characterizes flashbulb memories. Psychological Science, 14, 455-461. Similar Result for O. J. Simpson Murder Trial Psych 355, Miyamoto, Spr '14

  9. Memory for the O. J. Simpson Murder Trial:15 & 32 Months After the Trial • Over time, there are fewer "don't remember" responses, and more very inaccurate memories (Schmolck et al., 2000). 15 32 15 32"Don't Remember” Very Inaccurate Responses Responses Why Confidence Remains High While Accuracy Diminishes Over Time Psych 355, Miyamoto, Spr '14

  10. Why do people have high confidence in the accuracy of FBM's even though the accuracy declines? • 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. Return to Question: Is there a Special Mechanism for FBM's? Psych 355, Miyamoto, Spr '14

  11. 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 and rehearsed multiple times. Consolidation and reconstruction of memory over time. • Higher confidence in accuracy at time of retrieval. FBM's appear more vivid and more clear at time of retrieval. Definition of Schemas & Scripts Psych 355, Miyamoto, Spr '14

  12. Schemas &Scripts • Schema: Top-down knowledge & expectations that influence processing of a common situation or experience. • Examples: People have schemas for their experiences in a post office, a ball game, a classroom, shopping at the supermarket • Script: A concept of the sequences of actions that occur during a particular experience. • Examples: Eating at a restaurant; Going to the dentist; Buying something at a department store • Contrast between a schema and a script: • Schema is more static – the organization of an object or arrangement of objects. • Script is more dynamic – usually it refers to a type of human interactionthat occurs over time. Schemas & Scripts Influence Memory Psych 355, Miyamoto, Spr '14

  13. Schemas and Scripts Influence Memory • Memory can include information not actually experienced but inferred because it is expected and consistent with the schema • The constructive nature of memory can lead to errors or “false memories” Roediger/McDermott/Deese Experiment – Same as Coglab Psych 355, Miyamoto, Spr '14

  14. False Memory 1 Downloaded with permission from Thomas Pusateri’s website, http://iea.fau.edu/pusateri/home/index.htm, 29 December 2004. • The version of the demonstration shown here slightly modifies the original. Demonstration of the Deese (1959), Roediger & McDermott (1995) false memory paradigm. Instructions for the Experiment Psych 355, Miyamoto, Spr '14

  15. 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. Start of the Stimulus Sequence Psych 355, Miyamoto, Spr '14

  16. BED Psych 355, Miyamoto, Spr '14

  17. CLOCK Psych 355, Miyamoto, Spr '14

  18. DREAM Psych 355, Miyamoto, Spr '14

  19. NIGHT Psych 355, Miyamoto, Spr '14

  20. TURN Psych 355, Miyamoto, Spr '14

  21. MATTRESS Psych 355, Miyamoto, Spr '14

  22. SNOOZE Psych 355, Miyamoto, Spr '14

  23. NOD Psych 355, Miyamoto, Spr '14

  24. TIRED Psych 355, Miyamoto, Spr '14

  25. NIGHT Psych 355, Miyamoto, Spr '14

  26. ARTICHOKE Psych 355, Miyamoto, Spr '14

  27. INSOMNIA Psych 355, Miyamoto, Spr '14

  28. REST Psych 355, Miyamoto, Spr '14

  29. TOSS Psych 355, Miyamoto, Spr '14

  30. NIGHT Psych 355, Miyamoto, Spr '14

  31. ALARM Psych 355, Miyamoto, Spr '14

  32. NAP Psych 355, Miyamoto, Spr '14

  33. SNORE Psych 355, Miyamoto, Spr '14

  34. PILLOW Psych 355, Miyamoto, Spr '14

  35. ************************************************WRITE DOWN THE WORDS YOU SAW************************************************ Correct List of Words & Types of Erors Psych 355, Miyamoto, Spr '14

  36. Here are the stimulus words in the presented order: BED, CLOCK, DREAM, NIGHT, TURN, MATTRESS, SNOOZE, NOD, TIRED, NIGHT, ARTICHOKE, INSOMNIA, REST, TOSS, NIGHT, ALARM, NAP, SNORE, PILLOW Types of Memory Errors Omission errors: Words on the list that you didn't recall. Intrusion errors: Words not on the list that you thought were there. Common intrusion error:Sleep related words like: SLEEP, DROWSY or FATIGUE Interpretation of Experimental Results Psych 355, Miyamoto, Spr '14

  37. Interpretation of Results for the Roediger/McDermott/Deese Paradigm In this example, 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: 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. Schema-inconsistent omission errors. The word ARTICHOKE was the only non-sleep related word in the list. Subjects are more likely to omit ARTICHOKE than other words. Brewer's Experiment: Schema for "Office Room" Psych 355, Miyamoto, Spr '14

  38. 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? Predictions & Findings of "Office Room" Experiment Psych 355, Miyamoto, Spr '14

  39. Brewer & Treyens (1981): A Schema for "Office Room" Predictions: Memory will be biased .... • .... towards recall of schema- consistent information; • .... and against recall of schema- inconsistent information Findings: Correct recall: Desk, chairs, shelves Intrusion Errors: Books on shelves Omission Errors: Skull, small doll Schema consistent Schema inconsistent Advantages & Disadvantages of Schematic Influences on Memory Psych 355, Miyamoto, Spr '14

  40. Advantages & Disadvantages of Constructive Memory Advantages • Allows us to “fill in the blanks” (default knowledge). • Speeds up how quickly we can interpret or respond to a situation. • Helps create a meaningful narrative about our life experiences. • In general, cognition is inferential. • The schematic nature of memory – similar to Helmholtz’s “unconscious inference”. • Schemas & scripts help organize experiences into "chunks." Disadvantages • Sometimes we make errors without realizing it. • Sometimes we misattribute the source of information • Was it actually presented, or did we infer it? Intro to Source Misattribution & Eyewitness Testimony Psych 355, Miyamoto, Spr '14

  41. Familiarity + Source Misattribution Can Cause Mistaken Identifications • 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: Donald Thompson, a memory researcher.While watching Donald Thompson on TV, a woman who was attacked in her home. Later she identified him as the attacker. Experimental Study of Source Misattribution Psych 355, Miyamoto, Spr '14

  42. Source Misattribution & Eyewitness Identification See Figure 8.20 in Goldstein Robber Not Present Try to pick robber from photospread; male teacher present Experimental View male 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 Control View female teacher reading to students 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, 918-930. Same Slide with Emphasis Rectangles Psych 355, Miyamoto, Spr '14

  43. Source Misattribution & Eyewitness Identification See Figure 8.20 in Goldstein Robber Not Present Try to pick robber from photospread; male teacher present; robber not present. Experimental View male 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; robber present. Control View female teacher reading to students 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, 918-930. Results of This Study Psych 355, Miyamoto, Spr '14

  44. Results of Ross et al. (1994) View film of male teacher reading to students 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 incontrol group. • Source misattributionscan cause mistakenidentifications. View film of female teacher getting robbed by a man. Test:Pick robberfromphotospread. View film of female teacher reading to students 6040200 6040200 % Identification of Male Teacher % Identification of Male Teacher E C E C Robber not in photospread Robber in photospread Intro to Eyewitness Testimony Topic Psych 355, Miyamoto, Spr '14

  45. Eyewitness Testimony • Basic source of evidence in the Anglo-American legal system. • Historically more trusted than circumstantial evidence. • Of 248 people who were exonerated through the work of the Innocence Project, 75% were convicted on eyewitness testimony (Quinlivan et al., 2009; Scheck et al., 2000). Sources of Error in Eyewitness Testimony Psych 355, Miyamoto, Spr '14

  46. Sources of Error in Eyewitness Testimony • Intrinsic fallability of memory • Post-event suggestions by interested parties, esp. police. • Misleading post-event information (MPI) can bias memory • Misinformation effect (later in this lecture) • Misleading familiarity • Cross-racial identification • Line ups versus show ups. • Line up: Did one of these men do it? (People tend to respond as if the question is, who in this group looks the most like the person you saw?) • Sequential show up: Did Man A do it? Did Man B do it? etc. (Surprisingly less biased) Misinformation Effect Psych 355, Miyamoto, Spr '14

  47. Wednesday, May 13, 2014: The Lecture Ended Here Psych 355, Miyamoto, Spr '14

More Related