Chapter 9 & 10 Review
Key Terms from Lecture
Accessibility – refers to the claim by some theorists that memories are actually not forgotten,
rather they become inaccessible. In other words, there is a failure in retrieving the memory
rather than a loss of memory trace.
Availability – refers to the claim by some theorists that memories are, in fact, forgotten due to
permanent loss of the memory trace, or at least damage to it, making it unavailable.
Forgetting curve – a graphical depiction showing the rapid initial drop in retention of
information in memory followed by a relatively stable leveling off of information retained. The
forgetting curve was first demonstrated by Ebbinghaus’ method of savings in recall ability of
Jost’s law of forgetting – if two memory traces are equally strong at a given time, then the older
of the two will be more resistant to further forgetting.
Permastore – theoretical permanent storage facility for information that is well learned, as
proposed by Bahrick and Phelps (1984). After an initial period of forgetting, memories are
stable and remain in store forever.
Trace decay – the gradual weakening of memories resulting from the mere passage of time.
Cue-overload principle – interference due to a cue becoming associated with too many things,
making accessibility of a specific memory more difficult.
Interference – the disruption in memory retrieval ability due to the presence of related memories
being tied to the same or similar cues.
Proactive interference – occurs when old or previously learned information interferes with
memory for new information. For example, studying for a psychopharmacology exam
immediately after studying for biopsychology may result in proactive interference of
Retroactive interference – occurs when newly learned information interferes with memory for
old or previously learned information. For example, once a new telephone number is memorized
it may interfere with memory for the old telephone number.
Repression – forgetting that occurs without conscious awareness.
Suppression – forgetting that occurs under conscious control, i.e., an intentional, goal-directed
forgetting of memories. Psychogenic amnesia – forgetting the time period surrounding an anxiety-provoking event.
Memory loss usually lasts hours to weeks and is due to psychological reasons. It is neither
accidental nor consciously intended.
Retrieval inhibition hypothesis – hypothesis that first-list items are temporarily inhibited in
order to better remember the second-list items. However, first-list items are not forgotten.
Evidence for the availability of the memories for the first-list items comes from the observation
that participants are still able to recognize items from the first list despite not being able to recall
them, suggesting a problem of accessibility rather than availability.
Context-shift hypothesis – essentially a form of context-dependent memory in which the mental
context is changed between study of list 1 items and list 2 items, resulting in poorer recall of list
Reminiscence – term used by Ballard (1913) to describe the phenomenon observed when one
gradually becomes able to remember once forgotten material.
Hypermnesia – refers to the improvement in recall of material following repeated testing
sessions on the same material. It is most noticeable during free recall, but also occurs during
cued recall and recognition tests.
Post-traumatic stress disorder (PTSD) - Long-lasting reaction to severely stressful event, often
a single event that triggers reaction.
Key Concepts from Lecture
1. Availability vs. Accessibility Debate
– Memory IS forgotten. – Memory is NOT forgotten.
– Permanent loss of memory trace. – Not necessarily a loss of memory trace.
– Cues will not help retrieval. – Good cues will lead to retrieval.
2. Jost’s law of forgetting
a. States that if two memory traces are equally strong at a given time, then the older
of the two will be more resistant to further forgetting.
b. Characterized by the “forgetting curve.”
3. Forgetting curves demonstrated with many different types of information.
a. Nonsense syllables (Ebbinghaus, 1913).
b. Semantic information, e.g., a foreign language (Bahrick, 1984).
c. Public events (Meeter, Murre, & Janssen, 2005).
d. Classmates (Bahrick, Bahrick, & Wittlinger, 1975).
- Regardless of the type of information being tested, the general shape of the curve (sharp
decrease followed by leveling off and stabilization) remained remarkably similar to
Ebbinghaus’ (1913) original forgetting curve.
- Forgetting curves are particularly robust for recall but not recognition. - Led to the suggestion by Bahrick and Phelps (1984) that information that is well learned
to begin with is less susceptible to forgetting. They also noted that after initial
forgetting, the remaining information seemed to be in a theoretical permanent storage
facility called a permastore.
4. Linton’s (1975) autobiographical diary
a. Linton wrote in her diary daily for 5 years and tested herself over 6 years.
b. Events from the diary were then randomly selected and tested.
c. She noticed that multiple retrievals resulted in increased likelihood of retention.
d. This suggests that the more the information is retrieved, the more “permanent” the
c 1 test
s 2 tests
t 40 3 tests
e 4+ tests
0.5 1 2 3 4 5 6
Years after event
Implications: The more you test yourself, the stronger the memory and the less
likely it is to be forgotten.
5. Flashbulb memories
a. Very strong memories for events (although not always accurate), typically
involving a lot of emotion.
b. Can be remembered for a lifetime.
c. Suggests that emotion may play a significant role in long-term storage of
a. Skills such as riding a bicycle or playing a musical instrument seem to show no
signs of forgetting.
b. Possible explanations for this permanence:
ii. Automatization of the behaviors
i. The more related the memories, the more forgetting due to interference.
ii. Cue-overload principle – multiple memories that are associated with a
single cue end up competing for retrieval. iii. Retroactive interference – new information interferes with or disrupts
retrieval of similar old information.
e.g., New home address interferes with one’s memory for old home
iv. Proactive interference – old information interferes with or disrupts
retrieval of similar new information.
e.g., After studying for your Spanish midterm, you begin studying for your
German midterm. While quizzing yourself on German words, you
accidentally recall Spanish words instead.
b. Motivated forgetting
i. Repression - for example, psychogenic amnesia.
ii. Suppression - for example, intentional forgetting.
iii. Psychogenic amnesia
c. Controlling unwanted thoughts
i. Limit encoding
ii. Prevent retrieval
iii. Stop retrieval
d. Directed forgetting
Basden and Basden (1996)
Effect reflects differences in episodic encoding.
1. Remember instructions lead to elaborative semantic encoding for
2. Forget instructions stop rehearsal of that item.
ii. List-method Geiselman, Bjork, and Fishman (1983)
Cost: Forget instructions impair recall of items from the first list.
Benefit: Forget instructions reduce proactive interference on the second
Importantly, the items can be recognized later on, suggesting an effect
on accessibility, rather than availability.
e. Directed forgetting in the real world / Naturalistic directed forgetting
Joslyn and Oakes (2005)
i. Students made diary entries twice a day.
ii. Students split into two groups: ‘remember’ and ‘forget.’
1. Remember group – remember entries from first week as well as
new ones from second week.
2. Forget group – forget entries from first week and concentrate on
remembering new ones from second week. iii. Two weeks later, the students were asked to recall the events/entries from
both the first and second weeks.
1. The forget group had worse memory for the events from the first
2. Furthermore, forgetting occurred for both positive and negative
f. Possible explanations for the effects of list-method directed forgetting
i. Retrieval inhibition hypothesis – people can inhibit “to-be-forgotten”
material, thereby reducing activation of unwanted memories. However,
the memories remain available.
ii. Context shift hypothesis – “forget” instructions result in a new mental
state, i.e., a new context that separates list 1 from list 2 items. The new
context / new mental state during study of list 2 items is a poor retrieval
cue for list 1 items, resulting in poorer recall of list 1 items.
8. Recovery of memories
a. Spontaneous recovery
b. Repeated retrievals
i. Reminiscence (Ballard, 1913)
1. Asked school children to memorize a poem.
2. Over repeated trials, the children were able to recall more and
more lines of the poem that they could not remember previously.
ii. Hypermnesia (Erdelyi & Kleinbard, 1978)
1. Repeated recall attempts over a one week period.
a. Observed an improvement in recall over testing days, from
40% to over 80% of the materials. In other words, a
reversal of Ebbinghaus’s forgetting curve.
b. This was especially true for pictures more than words,
suggesting that hypermnesia occurs through visualization
and memory reconstruction.
iii. Hypermnesia in the real world (Bluck, Levine, & Laulhere, 1999)
1. More and more details of the OJ Simpson trial recalled over time.
2. Suggested that recalled details act as cues for more details which,
in turn, act as cues for even more details, etc.
iv. Cue reinstatement
1. Cues can trigger memory recovery.
e.g., Seeing your ex-girlfriend or boyfriend’s favorite dish on the
menu at a restaurant reminds you of some memories of her/him.
v. Autobiographical memory recall (Nadel, Greenleaf, & Ryan, 2008)
1. Weekly recall attempts for one month and a final recall attempt 1
2. Over each successive recall attempt, more and more details were
recalled. Demonstrates the effects of repeated retrievals with regard to
hypermnesia in autobiographical memory and, perhaps, the effects
of details acting as cues for more details.
c. Recovered childhood memories
i. Recovered memory therapy
ii. Hypnosis and age regression techniques
iii. Drugs, e.g., sodium amytal
iv. Imagination, role playing
v. Diaries and journals
vi. Therapy-induced recovered memories
1. Controversy over accuracy of recovered memories.
2. Sometimes true, sometimes false.
9. False memories
a. Lost in a shopping mall (Loftus & Pickrell, 1995)
i. The experiment showed that false memories of being lost in a shopping
mall were able to be “implanted” into adults’ memories.
ii. Half of those who subsequently reported being lost in a mall even
provided “details” of the event. Of course, these details were not true
because the event never occurred.
Key Terms from Lecture
Normal aging – in the context of memory, it is a term used to describe memory functioning associated
with the typical aging process as opposed to memory functioning related to dementia.
Longitudinal studies – a method for investigating the effects of aging on memory where a group of
individuals are enrolled in a study and tested multiple times over the course of several decades.
Practice effects – individuals tend to get better at taking tests after multiple exposures.
Cross-sectional studies – a method for investigating the effects of aging on memory where individuals of
different ages are enrolled in a study, grouped according to age, and tested once. Comparisons are then
made between age groups. Cohort effects – individuals born during different decades are probably going to differ in regards to
education, social factors, diet, etc., and these cohort factors may influence performance on the memory
Processing capacity – a term used to describe the ability to perceive and process information using
different, complex learning strategies.
Associative Deficit Hypothesis – hypothesis suggesting that decline in episodic memory related to aging
is attributable to impairment in the ability to bind or associate unrelated pieces of information.
Prospective memory – the mnemonic ability to remember to perform actions in the future without
Key Concepts from Lecture
What are some methods for studying aging and memory?
1. Longitudinal Studies: A sample of individuals that represent the general population are
followed over several years or decades and tested multiple times.
a. One advantage is it allows you to identify individual changes, which may help uncover
precursors of memory problems.
b. There are, however, several disadvantages. For example, it is expensive and time
consuming, there are high dropout rates, and there are typically “practice effects” (people
get better at taking the tests after repeated exposures).
2. Cross-Sectional Studies: Individuals of different ages are recruited and grouped according to
their age. Each individual is tested only once and performances for the different age groups are
compared to each other.
a. Since each individual is tested only once, there are no practice effects, it is less
expensive, there are lower dropout rates, and it takes less time.
b. There is one major disadvantage: “Cohort effects.” People born at different times may
be different in regards to diet, education, and a host of social factors and these factors
may modulate memory performance. Because these methods have different advantages and disadvantages, they can actually lead to different
3. Hybrid Method Studies: A group of individuals are recruited and tested. When the original
group of individuals are brought back for more testing, another cohort of individuals are added
from the same age range and tested for the first time.
a. Addresses the issue of practice effects by comparing the original group’s performance
on the second testing to the new group’s performance on their initial testing.
b. Addresses the issue of cohort effects by comparing the original group’s initial testing
to the second group’s initial testing.
This process can be repeated multiple times with additional groups added to the study each time.
How does aging affect working memory?
1. Working Memory span progressively declines with age, although effects are larger when the
test involves speed of processing or long term memory components.
2. Divided attention tends to decline with advanced age, but this may be largely attributable to
high cognitive loads involved in dual task paradigms. What did Charness (1985) find in regards
to chess playing and aging?
How does aging affect long term memory?
1. Episodic memory experiences a gradual decline with aging. This includes measures of:
a. Recall and recollection
b. Verbal and visual materials
c. Memory for names or places
d. Memory for everyday events
e. Memory for conversations
However, the magnitude of the decline may be related to several variables.
1. The type of test and the method for testing.
2. “Processing Capacity” of the learner (Craik, 2005). Older adults take longer to perceive and
process information and are less likely to spontaneously use elaborative strategies for
3. The level of environmental support during retrieval can also modulate episodic memory. For
example, tests that do not use very many external cues, such as free recall, are typically more difficult for older adults than recognition memory tests. The magnitude of decline seen with
aging, therefore, is more pronounced for tests that do not provide many external cues.
4. The Associative Deficit Hypothesis (Naveh-Benjamin, 2000): The difference in episodic
memory between younger and older adults is attributable to basic learning capacity.
a. Older adults are particularly impaired when they have to learn new associations between
information that are unrelated. For example, older adults have a harder time learning
associations between unrelated words (museum – wine) than related pairs (coffee –
b. This deficit appears to be related to impairment in the binding or associating of different,
unrelated pieces of information.
c. This deficit in binding has been found to be even greater when attention is divided
amongst multiple tasks.
How does aging affect prospective memory?
Prospective memory is a mnemonic ability that requires one to remember to perform an action at a future
point in time without explicit reminders. For example, remembering to deliver a message to a friend next
time you see her or remembering to attend a meeting at 5pm are examples of prospective memory. When tested in the laboratory, participants are engaged in an ongoing task and are required to remember
to complete the prospective memory task either:
a) after a specific time or
b) after a cue appears.
For example, the ongoing task can be playing a game of solitaire on the computer and the prospective
memory task can be remembering to press a red button every five minutes or each time you turn over an
How does aging affect semantic memory?
Semantic memory does not typically decline with age. In fact, it actually gets better in many areas.
1. Vocabulary has been found to increase with age.
2. One’s world knowledge increases with more experience, although speed of access to the
information might decline.
3. Written language is judged as “better” or more interesting, although the sentences are usually
shorter than those written by younger adults.
What are some theories for why memory is affected the way it is by aging?
1. The Reduced Processing Resources Theory: Older adults do not spontaneously engage in elaborative
learning strategies, and it is the inability to automatically engage in these strategies that accounts for
a. When younger adults are prevented from using elaborative strategies, their memory
performance looks similar to older adults.
b. Giving older adults good strategies for learning enhances performance, although not typically
to the same level of younger adults.
2. The Associative Memory Deficit (Naveh-Benjamin): Older adults have particular difficulty binding
information that was previously unrelated.
1. For example, numerous studies have found item vs. source memory effects. Older adults have
more trouble remembering whether a man or a woman spoke a sentence than they do
remembering whether they heard the sentence before. In this instance, the gender of the voice
and the sentence were previously unrelated, but needed to be associated.
e.g., Item vs. Source memory study by Glisky (2002).
Item = sentence Source = man or woman’s voice
What are some factors associated with aging well?
1. Good physical health has been found to be related to less cognitive decline, including memory.
2. Continued involvement in mental activities throughout the lifespan can help prevent declines. Explicit
memory training may help, but there is very little evidence to suggest that training results in generalized
3. An enriched environment?
Key Terms from Lecture
Engram – memory record.
Plasticity – the ability of neurons and the brain to change in response to experience.
Long-term neural plasticity – changes in the structure of neurons as a result of experience.
Immediate neural plasticity – changes in neuronal function as a result of experience.
Cell assemblies – networks of cells firing together.
Long-term potentiation (LTP) – the process by which cell assemblies, or networks of neurons,
become more responsive following synchronized firing that is consistent over time. According to
Hebb, restimulating any neuron in the network will increase the firing rate of the whole network. Habituation paradigm – a method used to study the immediate changes that occur in neuronal
function as a result of experience. Immediate changes are mediated through a decrease in
release of a neurotransmitter. In other words, there is a decrease in responding to repetitive
Sensitization paradigm – a method used to study the immediate changes that occur in
neuronal function as a result of experience. Immediate changes are mediated through an
increase in release of a neurotransmitter. In other words, there is an increase in responding to
Limbic system – brain structures involved in emotional processing and memory processing.
Includes hippocampus, amygdala, fornix, frontal lobes, and thalamus.
Papez circuit – an interconnected loop of brain structures originally thought to be the neural
basis for emotional experience. It was later determined to be critical for both emotion and
Post-traumatic amnesia – loss of memory for information from the onset of head trauma until
continuous memory is restored.
Retrograde amnesia – loss of memory prior to head trauma.
Anterograde amnesia – the inability to learn new information.
Hippocampus – brain structure in the medial temporal lobe shown to be important for memory
consolidation via LTP. It is one of the structures of the limbic system and part of Papez circuit.
Hippocampal amnesia – also known as the “classic amnesia.” This type of amnesia results
from damage to the hippocampus. Damage may be due to infections (e.g., encephalitis),
disease states (e.g., epilepsy), surgery (e.g., to relieve intractable seizures), stroke, etc. Deficits
are primarily in episodic memories. Thalamus – structure deep inside the center of the brain also shown to be important for
retrieval of memories. It is one of the structures of the limbic system and part of Papez circuit.
Thalamic amnesia – amnesia due to damage to the thalamus such as stroke or injury. Deficits
may be primarily in retrieval of information or in autobiographical memory.
Amygdala – structure located in front of the hippocampi shown to be involved in emotional
functioning, particularly fear/anxiety and conditioned learning. It is one of the structures of the
Item memory – memory for the informational content of an event.
Source memory – memory for the origin of information, contextual details of an event.
Key Concepts from Lecture
1. How is memory stored in the brain by neurons?
a. Mechanisms for learning must have the following properties:
i. Very fast
ii. Long lasting
iii. Relatively consistent
b. Plasticity – the ability of neurons and the brain to change in response to
i. Long-term – structural changes in neurons.
1. Cell complexity
ii. Immediate – functional changes in neurons.
1. Very fast changes in neurons mediated by increases or decreases in
neurotransmitter. Examples include the habituation and sensitization
responses of Aplysia.
c. Long-term potentiation (LTP) according to Hebb:
i. Networks of neurons that consistently fire together at the same time become
ii. Potentiation refers to the facilitation in restimulating the network’s
response/firing rate. It is important to note that restimulating any of the individual neurons in the network results in an increase in the whole
network’s response/firing rate.
iii. In other words, “neurons that fire together wire together” and “code” a single
iv. Hebb believed that LTP may have been the basis for complex learning.
2. Learning and retrieval of memories
a. Hebb’s two stages of memory formation
i. Short-term memory (STM)
1. The “activated” information is available in consciousness.
2. As long as the cell assembly continues reverberating, the information
is available in STM. Reverberation is analogous to rehearsal in STM,
but at the cell assembly level.
ii. Long-term memory (LTM)
1. If reverberations occur over a long enough period, structural changes
in the anatomy of the neurons occur.
a. Examples of structural changes include the following:
i. Increase in number of receptors, which helps
strengthen synaptic connections.
ii. Increase in production and release of
iii. The synaptic cleft decreases in size, thereby facilitating
b. Predicting a rat’s location and direction in a maze (McNaughton, Barnes, et al.,
i. Recorded activity from hippocampal neurons.
ii. Found networks of cells that fired in response to particular mazes that the
iii. It was even possible to predict a rat’s location and direction of movement
based on the neurons that were f