Transcript Chap15
BHS 499-07
Memory and Amnesia
Memory & Development
Memory Changes
Memory is not stable or static.
• Every experience we have changes our ability
to remember, distorts some info while making
other info easier to remember.
People’s ongoing development affects
memory.
• Infancy and childhood – skills get better.
• Old age – some skills decline but others
improve.
Infancy
Testing infant memory is difficult
because they cannot understand or
produce language.
Nonverbal behavior is studied to see
how it changes as a result of some
remembered experience.
• The meaning of these behaviors must be
inferred, so some findings are controversial.
Four Methods
Looking method – infants stare at the
novel, look away from the familiar.
Nonnutritive sucking – infants suck more
slowly when bored (seeing the familiar).
Conjugate reinforcement – mobile
kicking under different conditions.
Elicited imitation – recall of how to
assemble a toy or do some task.
Components in Infancy
Different memory components develop
at different rates based on readiness of
the brain to support them.
Semantic memory – infants can create
and use categories.
• Ability to make some basic distinctions at 3-4
months, superordinate at 14 mo, subordinate
not until 2 years.
Components in Infancy (Cont.)
Episodic memory – using conjugate
reinforcement:
• Infants 3 mo remember to kick after 1 week
• Rate of kicking varies with context (crib liner)
Using a new mobile in between makes it
less likely they will kick to the old one.
The length of time an imitated action can
be retained lengthens with age.
Components in Childhood
The brain continues to develop, so
development continues into adulthood.
Semantic memory – children develop
complex networks in areas of interest
(dinosaurs).
Schemas & scripts appear around age 3.
Categories begin to be used differently.
Components in Childhood (Cont)
Episodic memory – Older children infer
implicit associations (coffee stirred with a
spoon).
Older children tend to use structure more
often to remember (organizing furniture
by room).
Strategies for remembering emerge.
Other Childhood Changes
Working memory – rate and effectiveness of
rehearsal increases.
Capacity increases because speed of
processing increases (longer words retained).
Bigger knowledge base increases retention.
Better able to inhibit irrelevant information –
directed forgetting increases with age up to 10
years old.
More Childhood Changes
Metamemory – steadily increases with
time.
• Serial position – young children do not report
recent items, but older ones do.
Young children do not understand how
their memories work, but acquire
knowledge.
• Test taking strategies develop.
Problems with Studying Elderly
Longitudinal vs cohort studies.
Health problems distort results.
• Cohorts differ in level of education.
• Longitudinal studies difficult to carry out.
• Most elderly are healthy but those who are
not may have problems affecting memory.
Use it or lose it – decline in mobility
parallels cognitive decline.
Changes in Old Age
Neurological changes – decline in neural
conduction speed produces slowdown,
especially for complex tasks.
Declines in frontal lobes – dorsolateral
prefrontal lobes affected most.
• This is the area where working memory and
•
the central executive are found.
Decline in dopamine system.
Old Age Changes (Cont.)
Temporal lobe – older adults show global
problems with learning and retrieving
information.
Lateralization decreases – perhaps older
adults need to recruit more cells to do
the same job, decreasing specialization.
Imaging studies show that older adults
use their brains differently than younger.
Theories of Decline
Speed theory – speed affects memory
because some information is forgotten
during the stream of thought.
• Older adults process at 1.5 speed of younger.
Reduced working memory – reduced
attentional capacity.
• Light & Capps manipulated where a pronoun
appeared in a short story. The further from the
name, the more forgetting.
More Theories of Decline
Inhibition theory – related but irrelevant
info clogs the stream of thought.
• Difficulty doing directed forgetting task.
• Unable to suppress info from previous tasks.
Self-initiated processing – less able to
monitor their own memory processes.
• Recall more affected than recognition, so
problem may be retrieval and metamemory.
Components in Old Age
Episodic memory – decline in the
quantity of information remembered.
• Organization of the info stays the same.
• Impact of positive info increases, negative info
•
decreases, increase in mood congruency
effects.
More susceptible to retroactive interference,
larger fan effects.
Reliance on Schemas
Due to declines in remembering, reliance
on schemas is greater for older adults.
• More likely to make predictions using
schemas.
Episodic memory for details most likely
to be forgotten.
• Semantic memory is stable or improves.
• More likely to report semantic
autobiographical information, not episodic.
Source Monitoring Problems
Older adults are less effective at source
monitoring.
• Reliance on internal feelings instead of
•
•
•
memory for perceptual details leads to greater
reality monitoring failures.
Confuse perceptually similar sources (photos)
More willing to produce false memories.
Less likely to use environmental cues to aid
recall (less able to self-initiate).
Metamemory Problems
Prospective memory – worse than
younger people at both time-based and
event-based tasks.
• Self-initiated processing worse (take cookies
•
out of oven).
Not caused by inability to make a plan.
Better in real life because alternative
strategies are used.
Metamemory (Cont.)
JOLs & FOKs less accurate than for
younger people.
• Similar to younger people in ability to adjust
accuracy based on the info to be learned.
If a person thinks memory will be worse,
it declines.
• Activation of age-related stereotypes affects
performance of elderly but not young.
Strengths in Old Age
Semantic memory – little decline and
knowledge accumulates.
• Older adults outperform younger ones on
•
general knowledge tests.
Priming effects do not change.
Real-world knowledge is an advantage.
More Strengths
Episodic memory – some aspects
remain strong and even improve.
• Quantity vs quality – quantitative decline but
•
qualitative improvement.
Organization stays the same or improves.
Higher-level memory – mental models
improve. Better at remembering content
of news stories & sources.