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Malleability of Memories at Time of Retrieval Then Flashbulb Memories

Malleability of Memories at Time of Retrieval Then Flashbulb Memories. Psychology 355: Cognitive Psychology Instructor : John Miyamoto 05/12 /2014: Lecture 07-1.

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Malleability of Memories at Time of Retrieval Then Flashbulb Memories

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  1. Malleability of Memories at Time of RetrievalThenFlashbulb Memories Psychology 355: Cognitive PsychologyInstructor: John Miyamoto05/12/2014: Lecture 07-1 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 • Memories are malleable at time of retrieval.Application to treatment of PTSD. • Introduction to Everyday Memory • Autobiographical memories – the reminiscence bump • Flashbulb memories Experimental Design for Deconditioning Rat Response to Shock Psych 355, Miyamoto, Spr '14

  3. Experimental Design Day 1 Day 2 Day 3 Day 1 Day 2 Day 3 Day 1 Day 2 Day 3 Condition 1:Day 1: Tone + ShockDay 2: Drug; no tone; no shockDay 3: Freezes to tone (shows learning) Condition 2:Day 1: Tone + Shock + anisomycinDay 2: No drug; no tone; no shockDay 3: Does not freeze to tone(shows no learning) Condition 3:Day 1: Tone + ShockDay 2: Drug + tone, no shock.Day 3: Does not freeze to tone(shows no learning) Figure 7.23 Emphasis Rectangles for Explaining Design Psych 355, Miyamoto, Spr '14

  4. Experimental Design Day 1 Day 2 Day 3 Day 1 Day 2 Day 3 Day 1 Day 2 Day 3 Condition 1:Day 1: Tone + ShockDay 2: Drug; no tone; no shockDay 3: Freezes to tone (shows learning) Condition 2:Day 1: Tone + Shock + anisomycinDay 2: No drug; no tone; no shockDay 3: Does not freeze to tone(shows no learning) Condition 3:Day 1: Tone + ShockDay 2: Drug + tone, no shock.Day 3: Does not freeze to tone(shows no learning) Figure 7.23 Retrieval Makes Day 1 Learning Vulnerable to Change Psych 355, Miyamoto, Spr '14

  5. Summary of Main Finding Condition 1:Day 1: Tone + ShockDay 2: Drug; no tone; no shock Day 3: Freezes to tone (shows fear conditioning) Drug on Day 2 does not undo fear conditioning. Condition 2:Day 1: Tone + Shock + anisomycinDay 2: No drug; no tone; no shock Day 3: Does not freeze to tone(shows no fear conditioning) Combining drug with tone & shock on Day 1 prevents fear conditioning. Condition 3:Day 1: Tone + ShockDay 2: Drug + tone, no shock. Day 3: Does not freeze to tone(shows no fear conditioning) Combining drug with retrieval of memory of fear conditioning on Day 2 undoes fear conditioning. Retrieval Makes Day 1 Learning Vulnerable to Change Psych 355, Miyamoto, Spr '14

  6. Interpretation Day 1 Day 2 Day 3 Day 1 Day 2 Day 3 Day 1 Day 2 Day 3 • Retrieval makes the fear conditioning from Day 1 vulnerable to change. Combining retrieval with drug causes loss of conditioning. • Nader et al. (2000) state that the memory trace is "labile" during retrieval, i.e., its form can be changed at that time. Figure 7.23 Using Fragility of Memories During Retrieval to Treat PTSD Psych 355, Miyamoto, Spr '14

  7. Using the Fragility of Memories During Retrieval to Treat PTSD Brunet, A., Orr, S. P., Tremblay, J., Robertson, K., Nader, K., & Pitman, R. K. (2008). Effect of post-retrieval propranolol on psychophysiologic responding during subsequent script-driven traumatic imagery in post-traumatic stress disorder. Journal of Psychiatric Research, 42, 503-506. • Post-traumatic stress disorder (PTSD): Strong fear and stress responses are evoked by reminders of the initial traumatic event. • Brunet et al. asked whether human PTSD patients can loseor at least diminish their fear and stress conditioning bytechniques that are similar to Nader et al.'s demonstration that rats can lose their fear conditioning. • Study used propranolol, a drug that is used to prevent traumatic memories if administered immediately following a traumatic event. Propranolol reduces the fear & stress conditioning of trauma. • “Propranolol” – correct spelling“Probanolol” – incorrect spelling Brunet et al.'s Subjects Were PTSD Patients Psych 355, Miyamoto, Spr '14

  8. Brunet et al.'s Study of PTSD Subjects • PTSD patients: Childhood sexual abuse, motor vehicle accident, rape, being taken hostage. • Comorbid mental disorders included: major depressive disorder, panic disorder, social phobia, bulimia, generalized anxiety disorder. • Two scripts were prepared for each patient that described the events that produced the trauma for that patient. • 19 PTSD patients were randomly assigned to either a treatment condition or a placebo control condition. • Both Conditions: Patient hears a 30-second recording describing their traumatic experience. • Treatment Condition: Patient is injected with propranolol immediately following recording. • Control Condition: Patient is injected with a placebo that has no active ingredients. Analogy Between Brunet’s Treatment of PTSD & Fear Deconditioning in Rats Psych 355, Miyamoto, Spr '14

  9. Analogy Between PTSD Treatment & Conditioning HUMAN RAT Traumatic experience Tone + shock conditioning in the rat Listen to taped Rat hears tone without the shock description of traumatic experience Injection of propranolol Injection of anisomycin immediately after recall immediately after rat hears tone ? Later, the rat seems to have unlearned the fear conditioning to the tone. Later, will the human seem to have unlearned the fear conditioning to the traumatic memories? Test of Treatment Outcome – Patients Hear Taped Description of Trauma Psych 355, Miyamoto, Spr '14

  10. Test of Treatment • One week later, the patients listened to a taped version of the scripts that described their traumatic experience, and are asked to imagine the traumatic events while listening to the tape. • Physiological measures of stress and anxiety are taken while patients listen to the tape. • Question: When the patients hear the taped version of traumatic experience, will they experience fear, anxiety, etc. of PTSD? • I.e., has the drug treatment reduced or eliminated their tendency to associate fear responses with these memories. Experimental Results Psych 355, Miyamoto, Spr '14

  11. Brunet et al. Results Heart Rate Skin Conductance Corrugator EMG Tensing of Frowning Muscles • Grey = placebo group; Black = propranolol group • Result: Therapy reduces original fear conditioning. Return to Malleability of Memory During Retrieval Psych 355, Miyamoto, Spr '14

  12. Malleability of Memories During Retrieval • Learned associations can be lost during retrieval • Rats unlearned tone-shock connection • Humans unlearn (to some degree) the association between atraumatic episodic memory and the emotional response • Consolidation & Reconsolidation – memories can be strengthened during retrieval • Practice testing (retrieval) produces better future recall • Do these results contradict each other? • Stored representations can change during retrieval. • Usually the change makes the memory stronger, better organized, more linked to other memories, especially to retrieval cues. • The opposite can also happen, e.g., rats unlearn their fear conditioning, or humans become desensitized to memories of trauma. This special case is based on the injection of drugs that would not normally be present. No! Conclusions re Consolidation Psych 355, Miyamoto, Spr '14

  13. Conclusion re Consolidation • Consolidation occurs through reactivation of memories. • Hippocampus plays a major role in reactivation for recent memories. After the memories have been consolidated, the hippocampus plays a reduced role in retrieval of memories. • Memories are malleable during or shortly after retrieval. Introduction to Autobiographical Memory Psych 355, Miyamoto, Spr '14

  14. Autobiographical Memory • Autobiographical memories are memories of one's personal experiences and history. • Many autobiographical memories are episodic memories, e.g., I remember what I was doing and thinking when I heard that the World Trade Center was attacked on 9/11/2001. • Many autobiographical memories are semantic memories, e.g., I remember the name of my elementary school, but the name isn’t tied to a particular experience. Life Span Memory Retention Curve Psych 355, Miyamoto, Spr '14

  15. Anderson, S. J., & Conway, M. A. (1997). Representation of autobiographical memories. In M. A. Conway (ed.), Cognitive models of memory, 217-246. Life Span (Memory) Retention Curve Flashbulb Memories – Definition & Theoretical Questions Psych 355, Miyamoto, Spr '14

  16. 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

  17. Monday, May 12, 2014: The Lecture Ended Here Psych 355, Miyamoto, Spr '14

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