Retrieving Memory

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Article
 Read
the copy of the article provided
– This is an in class set, please don’t write
on it.
 Take
notes on all elements relating to
memory.
Retrieving Memory
Recognition, recall &
relearning
Problems
 Problems
in remembering can be due
to decay, interference, or repression.
In interference, previous memories
can interfere with present
remembering (proactive
interference) or information
remembered just recently can
interfere with past memories
(retroactive interference).
Explicit Memory


Deliberate, conscious recollection of facts and past
experiences
Recall tests - people are asked to retrieve memories
without the benefit of any hints or cues. A request to
remember everything that happened to you yesterday or to
recollect all the words in a list you just heard would be an
example of a recall test. Suppose you were briefly shown a
series of words: cow, prize, road, gem, hobby, string,
weather. A recall test would require you to write down or
say as many of the words as you could. If you were
instructed to recall the words in any order, the test would
be one of free recall. If you were directed to recall the
words in the order they were presented, the test would one
of serial recall or ordered recall.
Explicit Memory

Recognition tests require people to examine a list
of items and identify those they have seen
before, or to determine whether they have seen a
single item before. Multiple-choice and true-false
exams are types of recognition tests. For
example, a recognition test on the list of words
above might ask, “Which of the following words
appeared on the list? (a) plant (b) driver (c)
string (d) radio.” People can often recognize
items that they cannot recall. You have probably
had the experience of not being able to answer a
question but then recognizing an answer as
correct when someone else supplies it.
Implicit Memory
Using stored information without trying to
retrieve it. People often retain and use
prior experiences without realizing it.
 For example, suppose that the word
serendipity is not part of your normal
working vocabulary, and one day you hear
the word used in a conversation. A day
later you find yourself using the word in
conversation and wonder why. The earlier
exposure to the word primed you to
retrieve it automatically in the right
situation without intending to do so.

Implicit Memory
Priming
is the relatively
automatic change in
performance resulting from
prior exposure to information.
Priming occurs even when
people do not consciously
remember being exposed to
the information.
How priming works


In typical implicit memory experiments, subjects
study a long list of words, such as assassin and
boyhood. Later, subjects are presented with a
series of word fragments (such as a_ _a_ _in and
b_ _ho_d) or word “stems” (as______ or
bo_____) and are instructed to complete the
fragment or stem with the first word that comes
to mind.
The subjects are not explicitly asked to recall the
list words. Nevertheless, the previous
presentation of assassin and boyhood primes
subjects to complete the fragments with these
words more often than would be expected by
guessing.
Retrieval Cues
 Any
stimulus that helps us recall
information in long-term memory
 Two general principles govern the
effectiveness of retrieval cues –
encoding specificity and
distinctiveness.
Encoding specificity principle

According to this principle, stimuli may act
as retrieval cues for an experience if they
were encoded with the experience.
Pictures, words, sounds, or smells will
cause us to remember an experience to
the extent that they are similar to the
features of the experience that we
encoded into memory. For example, the
smell of cotton candy may trigger your
memory of a specific amusement park
because you smelled cotton candy there.
Distinctiveness

Distinctiveness determines the
effectiveness of retrieval cues. Suppose a
group of people is instructed to study a list
of 100 items. Ninety-nine are words, but
one item in the middle of the list is a
picture of an elephant. If people were
given the retrieval cue “Which item was
the picture?” almost everyone would
remember the elephant.
Déjà Vu and Jamais Vu
 Describe
a time where you could
swear that you remember doing
something before. You don’t know
when but you know you have done
the exact thing once before.
How it works


The sense of déjà vu (French for “seen before”) is the
strange sensation of having been somewhere before, or
experienced your current situation before, even though you
know you have not. One possible explanation of déjà vu is
that aspects of the current situation act as retrieval cues
that unconsciously evoke an earlier experience, resulting in
an eerie sense of familiarity.
Another puzzling phenomenon is the sense of jamais vu
(French for “never seen”). This feeling arises when people
feel they are experiencing something for the first time,
even though they know they must have experienced it
before. The encoding specificity principle may partly explain
jamais vu; despite the overt similarity of the current and
past situations, the cues of the current situation do not
match the encoded features of the earlier situation.
Tip of the Tongue
 Refers
to the situation in which a
person tries to retrieve a relatively
familiar word, name, or fact, but
cannot quite do so.
 Although the missing item seems
almost within grasp, its retrieval
eludes the person for some time
Theories
An intruding item essentially clogs the
retrieval mechanism and prevents
retrieval of the correct item. That is, the
person cannot think of one thing because
another gets in the way and blocks
retrieval of the correct name.
 Another idea is that the phenomenon
occurs when a person has only partial
information that is simply insufficient to
retrieve the correct item, so the failure is
one of activation of the target item.

Forgetting Curve
Forgetting
 In
1885, Hermann Ebbinghaus
discovered the exponential nature of
forgetting. The following formula can
roughly describe the forgetting:
– where R is memory retention, S is the
relative strength of memory, and t is
time.
Forgetting
Illustrates the decline of memory retention
in time. A related concept is the strength
of memory that refers to the durability
that memory traces in the brain. The
stronger the memory, the longer period of
time that a person is able to recall it.
 A typical graph of the forgetting curve
shows that humans tend to halve their
memory of newly learned knowledge in a
matter of days or weeks unless they
consciously review the learned material.

Forgetting
The speed of forgetting depends on a
number of factors such as the difficulty of
the learned material (e.g. how meaningful
it is), its representation and physiological
factors such as stress and sleep.
 The basal forgetting rate differs little
between individuals. The difference in
performance (e.g. at school) can be
explained by mnemonic skills.

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