Autobiographical Memories & Flashbulb Memories

Psychology 355: Cognitive PsychologyInstructor: John Miyamoto

5/11/2015: Lecture 07-1

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Outline

• Autobiographical memories♦ What are they? (I.e., what does this terminology mean?)♦ Are they different from other memories?

• Memory over the lifespan – the reminiscence bump

• Flashbulb memories♦ How do they change over time?♦ Do they involve mechanisms that differ from memory for less dramatic events?

Psych 355, Miyamoto, Spr '15 2Autobiographical Memory

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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.

• 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.

AM & Mental Imagery

AM & Mental Imagery

• AM’s often include memories of visual, auditory, olfactory or haptic aspects of the memory.

♦ Memory of a place might include a visual memory.♦ Memory of food might include visual or olfactory aspects.

• Greenberg and Rubin (2003)♦ Patients who cannot recognize objects also experience loss

of autobiographical memory♦ Visual experience plays a role in forming and retrieving AM

Psych 355, Miyamoto, Spr '15 4Do AM’s Involve Distinct Patterns of Brain Activity?

Do AM’s Involve Distinct Patterns of Brain Activity?

• Subjects (Duke undergrads) took photos of campus landmarks.

• Later subjects viewed photos during fMRI scan.

OWN Photos: Photos taken by the subject.

LAB Photos: Photos taken by someone else, not by the subject.

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Figure 8.1Goldstein, p. 209, based on Cabeza, Prince, Daselaar, Greenberg, Budde, Dalcos, et. al. (2004).

fMRI Results for OWN and LAB Photos (text description)

fMRI Results for OWN Photos & LAB Photos

• Both types of photos activated similar brain structures♦ Medial temporal lobe (MTL) (typical of episodic memory)♦ Parietal cortex (typical of scene processing)

• OWN-photos activated more of the♦ Prefrontal cortex (PFC) (information about self)♦ Hippocampus (recollection)

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These interpretationsinvolve theory (intelligent guesswork).

fMRI Results for OWN and LAB Photos (fMRI Images)

fMRI Images that Support Interpretation on Preceding Slide

Figure 8.2. fMRI response (a) in parietal cortex; (b) in prefrontal cortex (PFC); (c) in hippocampus.

• Yellow lines: Response to OWN photosBlue lines: Response to LAB photos

• OWN photos produce stronger response than LAB photos in PFC & hippocampus.

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(c) Hippocampus(a) Parietal cortex

(b) Prefrontal cortex (PFC)

Memory Over the Lifespan

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)

Reminiscence Bump

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Reminiscence Bump

• 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.

• The increase in memories for 10 – 30 years of age is called the reminiscence bump.

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Comparison Between Two Curves that Represent the Reminiscence Bump

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Reminiscence Bump

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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, 217-246.

Types of Memories that Make Up the Reminiscence Bump

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Types of Memories in the Reminiscence Bump

Rubin, Rahhal, & Poon (1998) find better memories during ages 10 – 30 for:• episodic memories• autobiographical facts,

e.g., personal preferences at the time

• memories for public events• memories for songs and music• memory for general knowledge learned at that time,

e.g., Academy Awards or World Series results, other current events

Why Is There a Reminiscence Bump?

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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 10 – 30 period).

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Figure 8.4. Frequency of memories over the lifespan. Red line – standard result. Blue dotted line – Hispanics who emigrated to U.S. at age 34 – 35.

Brief Comment re Childhood Amnesia

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Childhood Amnesia

• Childhood amnesia o Relatively few memories

before the age of 10o Especially few before the

age of 2 or 3

• What causes childhood amnesia?o Hypothesis: Immature brain,

especially hippocampus & prefrontal cortex.

o Hypothesis: Immature languageo Hypothesis: Immature self-concept

Summary re Memory over the Lifespan

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Summary: Life Span Autobiographical Memory

Three main periods

• Childhood Amnesia: Why does childhood amnesia occur?

• Remiscence Bump: Why is there a reminiscence bump?

• Normal forgetting in later life. Forgetting happens (no kidding!)

Outline – Flashbulb Memory Topic

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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.

o Do you remember where were you and what were you doing when you first heard about the attack on the World Trade Center?

o 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?