Download Chapter 4: Pattern Recognition

“Real World” Cognition
• Does memory remember? Seven sins of memory
Seven sins of memory: summary
Propositional Knowledge
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• Proposition: smallest unit of verifiable knowledge, can be falsified
We think what is in our heads are sentences, but sentences are built from propositions
Representing propositions in the head: semantic network
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A bit of knowledge: you know that John believes that Anna passed the exam.
Network can also carry relevant info about time (when did John believe this)
and place (where did John learn about this)
Remembering propositions (not sentences)
Sachs (1967):
There is an interesting story about the telescope. In Holland, a man named Lippershey was an eye-glass maker. One day his
children were playing with some lenses. They discovered that things seemed very close if two lenses were held about a foot
apart. Ltppersheybegan experimenting and his "spyglass" attracted much attention. He sent a letter about it to Galileo, the
great Italian scientist. Galileo at once realized the importance of the discovery and set about to build an instrument of his own.
He used-an old organ pipe with one lens curved out and the other in….
Base-He sent a letter about it to Galileo, the
great Italian scientist.
Semantic-Galileo, the great Italian scientist.
Sent him a letter about it.
Passive-A letter about it was sent to Galileo, the
great Italian scientist.
Formal-He sent Galileo, the great Italian
scientist a letter about it.
As intervening material increased,
subjects less and less able to distinguish
identical (base) sentence from changes
that preserve meaning (propositional
relations). But meaningful change
recognized.
Fan effect
As associative links increase, rt
increase. Greater interference among
competing associations
Levels of representation
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Situation model: narrative
events of story
Textbase: propositional
content of sentences, deep
structure
Surface form: exact words,
order of word, punctuation,
surface structure
Red=situation model
Blue=textbase
Yellow: surface form
Graph shows correct retention
over time
Source monitoring: Where did that memory come from?
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Found to be associated: elaboration – when one has added original ideas to an
existing information and working memory distraction or load – when one is
unable to devote needed cognitive resources to the information source.
False memories
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Experimentally inducing false
memory:
Subject learns list of word (bed, rest,
awake, pillow…)
At recall subject reports “sleep” as list
word
Effect greater effect with recognition
tests
Misinformation effect and false memory
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Misinformation: inaccurate
information provided after critical
event that changes memory for the
event
Ex: Loftus famous “car accident”
study
Implanting false memories
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Researcher’s supplied with childhood stories by parents
False story reinforced by doctored photo. When later asked about stories, subject
claims to remember false story
Autobiographical memory
• Bahrick et al (1975) studied memory for high school classmates.
Recognition far better than recall. Need for cues increases with time, but
memory impressive compared to most laboratory studies. Why?
• Effects of overlearning (same names practiced for years and years) and
distributed practice (practice spread out over years).
Infantile Amnesia: inability to remember early months/year
• Deficit is more explicit than implicit: learning and habituation effects
present from birth
• Not amnesia in the sense of memory loss, but inability to form enduring
memories because of immaturity of brain/cognitive system, lack of “sense
of self”
Memory over lifespan
Reminiscence bump: superior memory for early adulthood. May be due to
early adult “firsts,” (moving from home, first job, getting married, etc.)
Mid life amnesia: “routine” of life can make for poorer memory