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BHS 499-07Memory and Amnesia
Autobiographical Memory
Autobiographical Memory
When we meet people we introduce ourselves by exchanging memories.• Excerpts from our “life story”
Autobiographical memory covers events, situations and other knowledge that spans a person’s entire life.• Autobiographical memory is a narrative.
Episodic or Semantic?
Autobiographical memories are much more than just episodic memory.• More constructive and integrative.
• Spanning multiple events.
• Includes semantic-like generic info: where you work, phone numbers, etc.
Semantic memories are affected by autobiographical memory.• We know more about personal heroes.
Levels of Autobiographical Memory
Event level – detailed, referring to specific, individual events.
General level – referring to extended sequences or repeated series of events sharing a common component.
Lifetime period – broad, theme-based portions of a person’s life.• Relationship theme, work theme.
Event-Specific Memories
These most closely correspond to episodic memories.• Involve a common activity at a particular place
Lots of perceptual and contextual detail. Includes internal context material about
emotional reaction and physiological state.
May be lost or may endure over time.
Four Characteristics of Enduring Event-Specific Memories
Memories of originating events – a childhood experience that sets someone on a goal-related path to a career.
Turning points where a life is suddenly redirected.
Anchoring events for a belief system. Analogous events used to guide future
behavior – e.g., embarrassing moments.
General Event Memories
Two types:• A sequence of event-specific memories that
form a larger episode (such as the first day of a new job).
• A repeating event (such as a class taken). There is often a personal goal that is
affected by the extended event. Integrative and interpretive thinking used
to link events into a single memory trace.
Lifetime Period Memories
Long periods organized along some common theme.• Early childhood, career, education.
Recall of autobiographical memories beyond a general event is organized along a theme.
Evidence for the Hierarchy
This is a heuristic because there are many examples of memories that don’t fit – it is unclear where they belong.• Smaller parts can be nested into larger ones.
People have different aspects of their lives going on concurrently – overlap.
Neurological Evidence
Amnesics can recall general event and lifetime periods but not specific events.• S.S. (herpes encephalitis) – can remember
his job
• K.C. (motorcycle accident) – general semantic knowledge but not specifics, e.g., floorplan of house he grew up in, but not his own room.
• K.S. (rt. anterior lobectomy for epilepsy) – recalled specifics but not general info.
Memory as Life Narrative
We organize the events of our lives into a narrative structure, not semantic.• Our life is told as a story
We access info using basic event components: people, places, activities, other themes.• Anything stored with the event can be a cue,
e.g., odors.
Recall of Narrative Memory
When people remember, they recall clusters of memories around a theme.• People remember items related causally to
one another.
• People remember items that share the same person, place or activity – not time.
Semantic memory is used to make the memories more narrative in style.• Better at recalling forward, than backward.
Perspectives
Field memories – experienced from the original perspective, as lived.• More emotional, common in PTSD
Observer memories – experienced from outside ourselves, perhaps even watching ourselves, detached.• We could not do this if memory were not
constructed.
• More likely to be older memories, self-aware.
Schema-Copy-Plus-Tag Model
The older memories become the more schema-consistent because schemas are used to fill in missing info.• We better remember the parts that are
unusual, so memory doesn’t feel stereotyped.
Model says people remember schemas plus tags with the deviations, making the memory unique.
Item-Specific vs Relational Processing
This distinction between schemas and tags is like the semantic distinction between item-specific and relational processing.• Difficult to tell which schema-consistent
events really happened and which didn’t.
• It is easy to tell how the event was different than the schema (tag contains that info), even though it may not be the most important info.
Infantile Amnesia
Our earliest memories come from around age 2-4.
Many reported memories from earlier ages actually come from seeing pictures or hearing family stories.
A lot of learning occurs during the first two years, but nearly all events are lost.
Explanations
Psychodynamic view – repressed by the developing superego because they involve fantasies about sex with parent.
Neurological view – the hippocampus is undeveloped at birth and only reaches adult form after a few years.
Schema organization view – infants do not yet have organized schemas.
More Explanations
Language development view – language is needed to form a coherent narrative.• Preverbal children do not translate knowledge
into verbal info until they learn how to talk. Emergent self view – infants lack a
sense of themselves as separate from environment, no “I” as causal agent.• Autobio memories construct around sense of
self.
Multicomponent Development Theory
There are a number of memory abilities or components that emerge to bring about autobiographical memory.• Adequate episodic memory system
• Knowledge of how adults think and talk about the world and the passage of time.
• How a person understands himself or herself. Different cultures have different offset
ages for infantile amnesia.
Reminiscence Bump
Memories of a person’s life are dominated by those from around age 20.
Free-listing of autobiographical memories shows:• Recency effect, standard forgetting curve into
the past.
• Bump between 15 and 25.
Explanations
Cognitive view – occurs because the memories around 20 are the first ones of their type, a primacy effect.• Life scripts may guide recall with positive life
transitions around the bump times. Neurological view – people reach their peak at
the bump time, declines after. Identity formation view – people decide who
they are at that time in life with better connectivity.
Flashbulb Memories
Vivid memories with great detail, relatively resistent to forgetting:• Challenger explosion, Princess Di’s death,
9/11
• Include memory for the context, not just event
“Now Print!” mechanism in neural coding – original explanation but no support.
Normal memories, not special.
Accuracy of Flashbulb Memories
Because they are like normal memories, inaccuracies can creep in over time, they can be forgotten.
Because they are emotionally charged, people believe they are more accurate.• The stronger the emotional reaction, the more
the memory is believed.
• Pearl Harbor example – no baseball in Dec.
How are they Formed?
What we remember better is our reaction to the event, not the event itself.
Distinguishing qualities:• The event must be novel (surprising) – less
likely to be affected by interference.
• The event must have serious consequences for the person experiencing it.
• An intensive emotional reaction must occur.
What Strengthens Them?
Emotionally intense events raise arousal which aids memorization.
More attention, more elaborative processing and more reminders lead to better recall.
Events are rehashed repeatedly, so more practice.
Knowledge is needed for elaboration.