Consolidation of Memories. Memory in the Real World

Transcription

1 Finish: Consolidation of Memories. Begin: Memory in the Real World Psychology 355: Cognitive Psychology Instructor: John Miyamoto 05/08/2018: Lecture 07-2 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 The cycle of consolidation Autobiographical memory Memory over the life-span; the reminiscence bump Flashbulb memories Lecture probably ends here Memory schemas Constructive memory Eyewitness memory The Cycle of Consolidation Psych 355, Miyamoto, Spr '18 2

3 The Cycle of Consolidation Cycle of consolidation (JM s term): Repeatedly retrieving some memories. Possibly modifying the memories. Reconsolidating the memories, possibly with modifications. The cycle of consolidation happens spontaneously in many different situations. Psych 355,, Miyamoto, Spr '18 Image of a Man Thinking About an Argument with Significant Other 3

4 Not-So-Instant Replay of Interpersonal Conflict I asked but she her said why she so ABC! EFG? I thinks said XYZ. she JKL...., doesn t etc., etc., care etc., if PQR! Psych 355, Miyamoto, Spr '18 Image of a Man Thinking About How to Compute a T-Test 4

5 Statistics Problem Solving How do Does I calculate it What s matter the a if T-test? difference the What s between the..., formula etc., the etc., for etc., SS... Pooled? standard What deviation are the and degrees the standard of error? sample sizes... are different?... freedom of... SS pooled? Psych 355, Miyamoto, Spr '18 Dwelling On Something Involves Lots of Retrievals 5

6 Psych 355, Miyamoto, Spr '18 Start Autobiographical Memory 6 Dwelling on Something Usually Involves Lots of Retrieval Retrieval creates the potential for modification of memories. Retrieval-induced memory change happens often. We spontaneously engage in thinking patterns that cause retrieval-induced memory change. This is the cycle of consolidation. Retrieval induced memory change is a tool for better study habits. Retrieval induced memory change is a tool for clinical modification of memories. My Guess (only a guess): * Retrieval-induced memory change is generally a beneficial adaptation. * Occasionally it causes systematic errors and possible harm.

7 Psych 355, Miyamoto, Spr '18 7 Memory over the Life Span Autobiographical Memory (AM) Autobiographical memories are memories of one's personal experiences and history. Many autobiographical memories include episodic memories. E.g., I remember listening to a lecture on statistical theory last week, i.e., I remember where I was sitting in the room, who was around me, etc. Memory of a place might include a visual memory. Memory of food might include visual or olfactory aspects. Many autobiographical memories include semantic memories. E.g., I remember the name of my elementary school, but the name isn t connected to a particular experience. E.g., memory of an your own actions might include a memory of why you were doing what you were doing, and whether the action was successful.

8 Memory Over the Lifespan What events are remembered well? Significant events in a person s life Highly emotional events Transition points (periods of rapid change in personal situation) Psych 355, Miyamoto, Spr '18 Reminiscence Bump 8

9 Number of Memories Recalled Reminiscence Bump Procedure: Memories are cued by words that have been tested for producing many memories. Childhood Amnesia Reminiscence Bump Forgetting "movies", "riots", "storm", etc. Method is a version of cued recall. If a person over 40 years old is interviewed, typically most memories pertain to the recent past or to the period between 10 & 30 years of age Age at Encoding (Years) The increase in memories for years of age is called the reminiscence bump. Comparison Between Two Curves that Represent the Reminiscence Bump Psych 355, Miyamoto, Spr '18 9

10 Number of Memories Recalled Reminiscence Bump Childhood Amnesia Reminiscence Bump Forgetting Age at Encoding (Years) Goldstein Figure 8.3: Percentage of memories from different ages, recalled by a 55-year-old, showing the reminiscence bump. Based on Schrauf & Rubin (1998) The figure on the right is from: Anderson, S. J., & Conway, M. A. (1997). Representation of autobiographical memories. In M. A. Conway (ed.), Cognitive models of memory, I added the vertical red lines to the figure. Types of Memories that Make Up the Reminiscence Bump Psych 355, Miyamoto, Spr '18 10

11 Number of Memories Recalled Types of Memories in the Reminiscence Bump Rubin, Rahhal, & Poon (1998) find better memories during ages for: episodic memories. autobiographical facts, e.g., personal preferences at the time. memories for public events. memories for songs and music. Childhood Amnesia Reminiscence Bump Age at Encoding (Years) memory for general knowledge learned at that time, e.g., Academy Awards or World Series results, other current events. Forgetting Why Is There a Reminiscence Bump? Psych 355, Miyamoto, Spr '18 11

12 Why Is There a Reminiscence Bump? Self-image hypothesis: Memory is strongest for events associated with personal identity formation. Cognitive hypothesis: Encoding is better during periods of rapid change that are followed by stability. Cultural life script hypothesis: There is a script for a typical life in a given culture. Memory is strongest for important events in this life script, e.g., graduation, getting a job, marriage,... (often in the period). Figure 8.4. Frequency of memories over the lifespan. Red line standard result. Blue dotted line Hispanics who emigrated to U.S. at age Brief Comment re Childhood Amnesia Psych 355, Miyamoto, Spr '18 12

13 Number of Memories Recalled Childhood Amnesia Childhood amnesia Relatively few memories before the age of 10 Childhood Amnesia Reminiscence Bump Forgetting Especially few before the age of 2 or 3 What causes childhood amnesia? Hypothesis: Immature brain, especially hippocampus & prefrontal cortex. Hypothesis: Immature language Hypothesis: Immature self-concept Age at Encoding (Years) Summary re Memory over the Lifespan Psych 355, Miyamoto, Spr '18 13

14 Number of Memories Recalled Summary: Life Span Autobiographical Memory Three main periods Childhood Amnesia: Why does childhood amnesia occur? Childhood Amnesia Reminiscence Bump Forgetting Remiscence Bump: Why is there a reminiscence bump? Normal forgetting in later life. Forgetting happens (no kidding!) Age at Encoding (Years) Outline Flashbulb Memory Topic Psych 355, Miyamoto, Spr '18 14

15 Flashbulb Memories (FBM's) Hypothesis: Memory for a dramatic or shocking event is preserved as if a photographic image was made by using a flashbulb with a camera. Do you remember where were you and what were you doing when you first heard about the attack on the World Trade Center? Do you have memories of a major accident, e.g., a car accident? QUESTIONS: Do flashbulb memories differ in strength 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 Autobiographical Memories that Lasts a Long Time? Psych 355, Miyamoto, Spr '18 15

16 What Creates AM s that Last a Long Time? Self-generation of associations (connecting a memory to other knowledge) Distinctiveness Personal importance causes repeated retrievals of a memory. Consolidation & reconsolidation. Distributed practice as opposed to massed practice 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. Do FBM's Involve a Special Memory Mechanism? Psych 355, Miyamoto, Spr '18 16

17 Is There A Special Memory Mechanism for Flashbulb Memories (FBMs)? Psych 355, Miyamoto, Spr '18 17 Are FBM's Accurate? 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.

18 Accuracy of FBM's Mixed evidence Neisser & Harsch (1992) Subjects filled out a questionnaire within 1 day of Challenger disaster (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 '18 18

19 Talarico: Time Course of an FBM Talarico, J. M., & Rubin, D. C. (2003). Confidence, not consistency, characterizes flashbulb memories. Psychological Science, 14, 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. Psych 355, Miyamoto, Spr '18 Graphs Showing Decrease in Accuracy but not Decrease in Certainty for FBM 19

20 Psych 355, Miyamoto, Spr '18 Summary of Results Depicted in these Graphs (Redundant) 20 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.

21 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. Similar Result for O. J. Simpson Murder Trial Psych 355, Miyamoto, Spr '18 21

22 Tuesday, 8 May, 2018: The Lecture Ended Here Psych 355, Miyamoto, Spr '18 22

23 Memory for the O. J. Simpson Murder Trial: 15 & 32 Months After the Trial Percentage of Sample Subjects were interviewed 3 days after the verdict in the O. J. Simpson murder trial. Answered questions about their thoughts on the trial, e.g., how did you learn of the verdict? how do you feel about the verdict? Schmolck, H., Buffalo, E. A., & Squire, L. R. (2000). Memory for distortions develop over time: Recollections of the O. J. Simpson trial verdict after 15 and 32 months. Psychological Science, 11, Subjects were randomly assigned to a 2nd interview 15 or 32 months after the 1st interview. Subjects were asked to recall what they thought at the 1st interview "Don't Remember Very Inaccurate Responses Responses Over time, there are fewer "don't remember" responses, and more very inaccurate memories (Schmolck et al., 2000). Why Confidence Remains High While Accuracy Diminishes Over Time Psych 355, Miyamoto, Spr '18 23

24 Why do people have high confidence in the accuracy of FBM's even though the accuracy declines? Psych 355, Miyamoto, Spr '18 24 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.

25 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 25 A Schema for "Office Rooms"