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CHAPTER 7
CH
MEMORY
CHAPTER OUTLINE
Memory
1) Types of Memory
a) Why No One Experiment Characterizes All of Memory:
i) Ebbinghaus’ Pioneering Studies of Memory: Ebbinghaus started the
experimental study of memory. He used nonsense syllables and himself as the
only subject. His findings showed a very quick decline in memory–1/2
forgotten within 24 hours.
ii) Differences Among Individuals Because of Interference: One reason
Ebbinghaus’ memory loss was so great was the amount of memory
interference he experienced. Proactive interference refers to the difficulty
remembering recently learned information that is caused by similar previously
learned information. Retroactive interference is the converse process - when
more newly learned information increases forgetting of the older information.
Ebbinghaus experienced very substantial proactive interference.
iii) The Importance of Meaningfulness: Ebbinghaus’ work also highlights this
point – that people remember meaningful materials better than less
meaningful materials (like nonsense syllables).
iv) The Importance of Distinctiveness: We tend to remember distinctive or
unusual material. (This feature of memory will be encountered again when we
discuss stereotyping and other problems of social cognition.) This tendency is
called the von Restorff effect.
v) Dependence of Memory on the Method of Testing: Memory performance
depends to some extent on exactly how memory is tested. Recall, or simple
reproduction of material is the simplest form of memory testing but makes the
heaviest demands on the learner. The performance of the person tested is
better in a cued recall format – this is a method in which one gets significant
hints about the material that should be remembered. In recognition, one
identifies the correct item from among several choices. The savings (or
relearning) method relies on the fact that one typically relearns old
information more quickly than one learns something new. This method is
more sensitive to weak memories.
b) The Information-Processing View of Memory: According to the informationprocessing view, memory works like a computer - information enters the system,
is processed and coded in various ways and then stored.
i) The Sensory Store: The sensory store is a very brief storage of sensory
information. Some cognitive psychologists classify this as closer to the
process of perception than that of memory.
ii) Short-Term Memory Versus Long-Term Memory: The traditional
information-processing theory distinguishes between short-term memory,
storage of the information that someone has just been experienced and longterm memory, which is the relatively permanent storage of mostly meaningful
information. These two stages of memory differ in their dependence on
retrieval cues, vulnerability to decay, and capacity.
iii) Dependence on Retrieval Cues: Reminders or hints (retrieval cues) are useful
for information stored in long-term memory, but not short-term memory.
Retrieval cues differ in their effectiveness.
iv) Differences in Capacity: Long-term has a large, difficult-to-measure capacity;
short-term memory capacity is small, and can be easily measured with a
memory span task. The capacity of short-term memory is around seven items;
the size of an “item” can differ–information can be organized into more
meaningful chunks. With practice, people can learn increasingly large chunks.
v) Decay of Short-Term Memories Over Time: The mere passage of time does
not impact long-term memory much, but short-term memory decays quickly.
Peterson and Peterson demonstrated quick decay of short-term memory by
using a distracter task to prevent rehearsal. But this decay does not occur with
meaningful materials; also, short-term memory loss depends on interference
as well as decay.
vi) The Transfer from Short-Term Memory to Long-Term Memory: Early
thinking was that rehearsal in short-term memory leads information to
consolidate and form a long-term memory. But consolidation depends on
more than time, and time alone does not guarantee consolidation. Short-term
memory does not appear to be a simple “holding stage” on the way to longterm memory.
vii) Working Memory: The concept of working memory has taken the place of
short-term memory. The “working” in “working memory” takes into account
that this in stage of memory is the information with which you are working at
the moment. It includes three components: a central executive that manages
shifts in attention, a phonological loop that stores and rehearses spoken
information, and a visuospatial sketchpad that stores and manipulates visual
information.
c) Other Memory Distinctions: There are two major ways to divide up long-term
memory.
i) Declarative memory is the storage and recall of factual information, while
procedural memory is memory for motor and routine cognitive tasks. Longterm declarative memory can also be divided into semantic memory, the
memory of general principles (such as your academic learning) and episodic
memory, the memory for specific events in a person’s life, generally
containing details of when and where events happened. It is like the “photo
album” of your life.
ii) Episodic memory tends to be more fragile and subject to decay or distortion.
Source amnesia is a common and non-serious problem that all people
experience – we remember what we learned but forget from whom or where
we learned it (remember the semantic but forget the episodic).
2) Long Term Memory Storage
a) Meaningful Storage and Levels of Processing:
i) According to the levels of processing principle, the ease with which we
retrieve a memory depends on the number and types of associations we have
made with that memory. The level of processing of material can be improved
either by focusing on individual items and relating them to information that
has already been learned, or by looking for relationships among items.
ii) Monitoring of one’s own understanding is important for memory. A
systematic way to do it is the SPAR method (survey, process meaningfully,
ask questions, review.) This provides a useful “self-checking” strategy.
iii) The Effects of Spacing One’s Study Sessions: People tend to remember items
better from the beginning and end of lists, this tendency is known as the
serial-order or serial-position effect. One explanation for the primacy effect is
increased rehearsal for early items. An explanation for the recency effect is
that the items are still held in the phonological loop of working memory.
Recent research indicates that the quality of long-term memory and effective
remembering depend on studying and reviewing under varying conditions and
with substantial intervals between sessions.
iv) The Use of Special Coding Strategies: Memory is stored in terms of retrieval
cues, little bits of related information, or hints that might help you regain the
complex memory when you need to recall it later.
v) Encoding Specificity: The encoding specificity principle states that the
associations formed at the time of the original encoding will act as the most
effective retrieval cues. The state-dependent memory principle describes the
general finding that long-term memories are more easily retrieved when the
individual is in the same physiological state as during the original learning.
vi) Emotional Arousal and Memory Storage: People usually remember events
that are associated with strong emotions very well. Research on flashbulb
memories demonstrates that arousal may lead to increased vividness and
intensity of memory, but not necessarily to increased accuracy. The
memorable quality of emotional events may be related to stimulation of
norepinephrine synapses, and increased blood glucose levels that facilitate
brain functioning.
c) Mnemonic Devices: A mnemonic device is a memory aid that requires each item
to be encoded in some special way. These include thinking of a story that reminds
one of the materials. The method of loci involves memorizing a series of places,
and associating the items to be remembered with one of those places. The peg
method involves memorizing a set of objects (pegs) and associating each item
with a peg.
3) Retrieval of Memories
a) Reconstruction of the Past: During a life experience, we construct a memory. We
are not paying attention to every detail. When we try and retrieve that memory,
we put together an account based on what was preserved in long-term memory
and our expectations of what must have happened. We reconstruct the memory
partially based on inference. Thus we say that memory is a reconstruction of an
event.
i) Reconstruction and Inference in List Memory: A powerful false memory can
be produced by presenting a list of related words, and omitting a key word–
this key word is often falsely remembered.
ii) Reconstructions of Stories: The less certain one is of a story, the more likely
one is to rely on expectations to reconstruct it.
iii) Hindsight Bias: People have a tendency to recollect events in such a way that
their memories match how the events actually turned out–a hindsight bias.
iv) Eyewitness Identifications: Witnesses often give inaccurate accounts of
crimes and other events. Memory is so suggestible that it is very difficult to
ask totally unbiased questions, or have fair lineups.
b) The False Memory Controversy: A major controversy in psychology involves the
phenomenon of recovered memories–“reports of long-lost memories, prompted
by clinical techniques.” Recovered memory claims can be quite bizarre, and even
when they are not, their accuracy is almost always uncertain.
i) Repression: Freud introduced the notion of repression, a process in which a
memory, motivation, or emotion is moved from the conscious mind to the
unconscious mind. Research on memory and forgetting has not supported the
existence of the phenomenon. However, it is very difficult to prove that the
recollected events did not occur, particularly in the case of disturbing but
plausible incidents of traumatic abuse. The fact that some people may in fact
repress or forget memories of traumatic events is not a justification for the use
of unreliable clinical techniques (such as hypnosis) to recover those
memories. A number of experiments have produced credible evidence that
leading a client or interviewee can result in distorted and false memories.
ii) Children as Eyewitnesses: Children tend to be more vulnerable to suggestion
than are adults, and their memory accuracy can suffer in a threatening,
suggestible environment. The recommendations for enhancing children’s
accuracy are to provide a suggestion/pressure-free non-threatening
environment, reasonably soon after the event, and to try to be sure that the
questions are phrased in a comprehensible manner given the child’s level of
cognitive development. Repetition of a question may help or not help - a
young child may answer differently each time the question is asked but in
some cases the repetition does help the child’s memory. The use of
anatomically correct dolls has not been shown to improve accuracy of recall.
4) Amnesia
a) “Normal” Forgetting: The shape of the forgetting curve shows that most
memories fade rapidly, but the longer a memory is held, the less it is forgotten.
Forgetting occurs through the effects of interference (described above), decay
(fading due to time passed, plus the effects of interference), and the inability to
access the appropriate retrieval cues.
b) Amnesia After Brain Damage: Amnesia refers to devastating loss or deterioration
of long-term (mostly declarative) memory.
i) The Case of H. M., a Man with Hippocampal Damage: H. M was a patient
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suffering from extremely severe epilepsy; surgeons removed his hippocampus
along with some surrounding brain areas. The result was severe memory
problems, in particular, anterograde amnesia, which is the inability to store
any new long-term memories. He also suffered moderate retrograde amnesia,
the loss of memory for events that occurred shortly prior to the brain damage.
He could form normal short-term memories, and could also acquire and retain
new skills (procedural memory). He displayed severe deficits in declarative
memory.
Frontal-Lobe Amnesia: Frontal lobe damage produces amnesic effects similar
to hippocampal damage, plus some unique memory impairments. Frontal lobe
damage is associated with Korsakoff’s syndrome. This condition results from
a prolonged deficiency of vitamin B1, usually resulting from chronic heavy
alcohol consumption. These patients have trouble remembering where and
when events took place, and engage in confabulation, in which they fabricate
information in an attempt to fill in the gaps in their memory.
Implicit Memory in Amnesic Patients: People with amnesia tend to have poor
factual memories, but intact procedural memories. Amnesiacs show preserved
performance on tests of implicit memory, which do not require conscious
recollection for successful performance. On tests of explicit memory
amnesiacs show much more severely impaired performance. Explicit memory
requires that the individual recognize the correct answer, and be aware that
long-term memory is being tapped.
Implications of Brain-Damage Amnesia: Results demonstrating dissociations
between the various forms of long-term memory provide evidence for the
existence of these forms of memory.
Memory Impairments in Alzheimer’s disease: Alzheimer’s disease is a
condition occurring in middle or old age in which there is a gradual increase
of memory loss, confusion, depression, disordered thinking and impaired
attention. During the course of the disease there is a gradual accumulation of
harmful proteins in the brain, which kills off brain cells. Eventually the
condition results in profound disability and death. A genetic connection has
only been established for early onset Alzheimer’s disease. There is evidence
that lifestyle (diet, physical and mental activity levels) as well as genetics
plays a role in the onset of the disease.
Infant Amnesia: The relative sparseness of declarative memories from early
childhood (we have few memories of their our lives prior to age 5) is termed
childhood amnesia or infant amnesia. Psychologists have proposed a number
of mechanisms to account for childhood amnesia, including repression, the
differing nature of childhood and later memories (nonverbal vs. verbal),
immaturity of the hippocampus, and lack of a “sense of self” early in life.
Rather than being a true “amnesia” it now appears to be a normal result of
lack of brain maturity and language ability.