Download Chapter 8 Answers to Before You Go On Questions What are

Chapter 8
Answers to Before You Go On Questions
1. What are encoding, storage, and retrieval? Simply put, memory is the faculty for recalling
past events and past learning. Psychologists generally agree that it involves three basic
activities: (1) encoding (getting information into a form appropriate for storage in memory in
the first place), (2) storage (retaining memories for future use), and (3) retrieval (recapturing
memories when we need them).
2. What are the three memory stores suggested by the information-processing model of
memory?The information-processing model of memory has its roots back in early computer
science (Atkinson & Shiffrin, 1968) and was intended to chart the ways that, like computers,
humans process information from their senses into memory. There are three suggested
memory stores used by the information-processing model of memory: (1) sensory memory
(holds sensory information, lasting up to half a second for visual inputs and 2–4 seconds for
auditory inputs; has a large capacity), (2) working memory (holds information temporarily
for analysis, lasting up to 30 seconds without rehearsal, with a limited capacity for about 5–9
items, and (3) long-term memory (permanent storage with a relatively unlimited capacity).
3. How does increased attention affect automatic and effortful processing? Automatic
processing (encoding of information with little conscious awareness or effort) and effortful
processing (encoding information through careful attention and conscious effort) are both
variations on our ability to process information. There are key differences between these two
kinds of processing. First, the encoding of information by effortful processing tends to be
disrupted when a person is forced to perform other tasks or to attend to other information
while trying to encode the information at hand (think about playing an intense video game
and talking on the phone). In contrast, automatic processing is disrupted only slightly by the
performance of other tasks (think about pouring a cup of coffee while talking on the phone).
Therefore, increasing the amount of attention focused upon a particular task has a much
larger and positive effect on effortful processing than automatic processing, which is not
significantly enhanced by a person’s extra efforts to attend and encode.
4. Why is it more effective to study all term long, rather than in one massive session right before
a final exam? Information passes into long-term memory best when our rehearsal sessions
are spread out over a period of time rather than attempting to take in a great deal of
information all at once. This phenomenon (as we observed in Chapter 7) is known as the
spacing effect. Thus, distributed practice, such as studying material weekly followed by
reviews closer to the time of an exam, is usually more profitable than massed practice, such
as studying in one “cram” session just before an exam.
5. Which type of coding would most people use to remember someone’s face? Which type would
most people use to remember a person’s name? To remember someone’s face, typically we
would use visual code, or photographic memories. To remember a person’s name we would
likely employ the use of a phonological code, the repetition of the sounds of the letters to
form the name. Research suggests that people tend to favour phonological codes (as if they
were spoken) when recording verbal information, such as numbers, letters, and words. We
rely more on visual codes for non-verbal information, such as a person’s face or a speeding
car (Just & Carpenter, 2002).
6. What is chunking, and why would you want to use it? Chunking is one way of organizing
information to help enhance memory. If you watch a lot of hockey, you might chunk or
organize strings of single-digit numbers into times for goals in a game—1, 3, 4, 5, 2 might
become a goal at 13:45 of the second period. Chunking pieces of information together into
larger units enables us to encode more information in our working memory system, and it
also enables our working memory to store more information at a given moment.
7. What kind of information is stored in semantic memory and episodic memory? Are semantic
and episodic memories implicit or explicit memories? Semantic memory typically is a
person’s memory of general knowledge of the world. This includes both facts as well as
seemingly general knowledge (for example, bananas are yellow, there are 12 months in a
year, spiders have eight legs). Episodic memory, on the other hand, relates to a person’s
memory of personal events or episodes from his or her life (our memory of our high school
graduation, the birth of our first child, etc.). Both semantic and episodic memories are
considered explicit memories, that is, memories with conscious recall.
8. If researchers show people several pictures of small rodents, then find that a lot of people
include hamsters and mice when asked to name animals that make good pets, what has
happened? Why did it happen? The pictures of the small rodents had a priming effect on the
participants’ memories. As such, the pictures served as cues to recall similar memories,
making it more likely people would think of other small rodents (hamsters and mice) when
asked later about pets.
9. Why do many educators believe it is helpful to take an exam in the same room where you
learned the material? The retrieval of information from memory is facilitated by retrieval
cues—words, sights, or other stimuli that remind us of the information that we need.
Essentially, when we come across a retrieval cue, we enter our long-term memory system
and activate a relevant piece of information. Because the pieces of information in this
memory system are linked to each other in a network of associations, the activation of the
first piece of information will trigger the activation of related pieces until a complete memory
emerges. This is known as context (encoding [context] specificity). The original location
where you first learned a concept or idea is rich with retrieval cues that will make it more
likely you will be able to recall that information later if you are in the same location or
context.
10. How do strong emotions affect our memory processes? Some theorists suggest that strong
emotions may enhance memories by leading to increased rehearsal, elaboration, and
organization of a particular event, or that intense emotions may trigger a special memory
mechanism, producing emotional memories. What were you doing at 9:00 a.m. on Tuesday
May 2, 2006? Can’t remember off the top of your head? That’s not surprising. What were
you doing on Tuesday, September 11, 2001, at 9:00 a.m.? That memory is probably quite
easy to access.
11. How does the decay theory explain forgetting? The decay theory of forgetting suggests that
memories fade over time because of neglect or failure to access them over long periods of
time. This theory is built on the notion that memories leave a physical trace in the brain—a
so-called memory trace—when they are acquired. Theoretically, these traces fade away over
time if the person does not use them.
12. What is repression? Sigmund Freud’s theory of repression is a process in which we
unconsciously prevent some traumatic events from entering our awareness, so that we do not
have to experience the anxiety or blows to our self-concept that the memories would bring.
According to Freud, the repressed material is not lost, but rather hidden from consciousness.
He believed that this hidden material may influence later decisions or interpretations of
events, even though we are not aware of its impact in such cases. In short, the repressed
information takes on the form of an implicit memory.
13. A late night TV comedy show host suggests that supporters of one political party have
happier lives than members of the others. Although this person is obviously unqualified to
know, your friends have started to tell you it’s proven that members of this party have more
fun, so they’re thinking of switching parties. What might be happening to your friends’
memories? Just as retroactive interference causes us to forget something when we are later
exposed to new competing information, so too can exposure to new misinformation. This
new “information” that is inaccurate or misleading can distort our recall or lead us to
manufacture new memories.
14. The saying, “Elementary, my dear Watson,” did not appear in any of the writings of Sir
Arthur Conan Doyle, the author of the Sherlock Holmes series, yet millions of fans vividly
remember reading these words. What processes can explain this manufactured memory? We
often forget or are confused about where we have gathered information that is now stored in
our long-term memory system. This is known as source misattribution (remembering
information but not the source it came from, leading us to remember information as true from
unreliable sources). These source misattributions can render our memories of certain events
distorted or, in some cases, manufactured (Lindsey et al., 2004).
15. Which parts of the brain are most active in memory? How are these parts related to
neurotransmitters involved in memory? Based on a number of studies, researchers have
concluded that there is no specific place—no storehouse—in the brain where memories
reside (Dudai, 2001). Information in the brain is encoded across various neurons throughout
the brain. Among the most important structures of working memory, for example, is the
prefrontal cortex, a key structure within the neocortex; among the most important structures
in long-term memory are the hippocampus and other parts of the neocortex.
16. What is a neural network and how might long-term potentiation contribute to its formation?
Remembering that communication throughout the brain proceeds from neuron to neuron,
when we talk about certain pieces of information being closely linked to other pieces of
information in the long-term memory system, we are really saying that certain neurons in the
brain become predisposed to trigger other neurons. It appears that the repeated stimulation of
certain neurons greatly increases the likelihood that these neurons will respond to future
stimulation of the same kind, a phenomenon called long-term potentiation (LTP) (Wixted,
2006, 2004). LTP affects not just single neurons, but the networks of neurons that make up
neural circuits. The effects of LTP can last quite a long time (hence the name long-term
potentiation), long enough to be a key factor in the formation and retrieval of information.
17. Why are toddlers able to effectively remember faces, places, objects, and certain skills, but
are not able to remember the events of their lives very well? Brain regions holding different
types of memories do not develop at the same rate. That is, the brain circuits responsible for
storing memories of events seem to develop more slowly than the brain regions responsible
for storing information about language, motor skills, and simple associations. We know that
many memories about life events, often called episodic memories, are initially stored in the
hippocampus; the hippocampus is a late-developing brain structure, and this late
development might contribute to the inability to form episodic memories early on.
18. Why do the memories of elderly people tend to decline and what techniques seem to help
prevent or slow down memory problems? Certain parts of the brain, such as the
hippocampus, begin to shrink beginning in our twenties. A study of the brains of elderly
individuals found that the hippocampus was about 20 percent larger in those with excellent
memories than those suffering from Alzheimer’s disease (Winningham, 2010), a finding that
may also have implications for the memory losses that accompany normal aging. Brain
fitness approaches—using computer exercises and mental games to keep the mind “in
shape”—have become popular and are often recommended to elderly patients by health-care
professionals. Research has also demonstrated repeatedly that physical exercise also seems to
help prevent or slow down deficiencies and impairments of memory and other forms of
cognitive functioning (Hoveida et al., 2011; Smith et al., 2011).
19. Compare and contrast retrograde and anterograde amnesia. What are the likely causes of
both? Retrograde amnesia is an inability to remember things that occurred before the organic
disorder (known as an amnestic disorder) or event that triggered the amnesia. Anterograde
amnesia is an ongoing inability to form new memories after the onset of the disorder or
event. So in retrograde amnesia old memories are lost and new memories are formed, and in
anterograde amnesia old memories are maintained but there is an inability to form new
memories. Anterograde amnesia is often the result of damage to the brain’s temporal lobes or
mammillary bodies, areas that play a role in transferring information from working to longterm memory. Head injuries are a common cause of amnestic disorders; although mild head
injuries, for example, a mild concussion, rarely cause memory loss, almost half of all severe
head injuries do cause some permanent learning and memory problems (Sadock & Sadock,
2007). Another cause of amnestic disorders are brain surgeries.
20. What changes happen in the brains of people with Alzheimer’s disease? This gradually
progressive disease sometimes appears in middle age, but most often it occurs after the age of
65. People with Alzheimer’s disease form far more than ordinary numbers of neurofibrillary
tangles and senile plaques, brain changes that are normal features of aging up to a point
(Selkoe, 2002, 2000, 1991). Neurofibrillary tangles are twisted protein fibres found within
the cells of the hippocampus and several other brain areas. Senile plaques are sphere-shaped
deposits of a protein known as beta-amyloid protein that form in the spaces between cells in
the hippocampus, cerebral cortex, and several other brain regions, as well as in some nearby
blood vessels. The presence of so many tangles and plaques indicates that enormously
destructive processes take place in the brains of people with Alzheimer’s disease (MeyerLuehmann et al., 2008; O’Connor et al., 2008).
21. How do dissociative disorders differ from organic memory disorders? Organic memory
disorders all have physical brain-based issues associated with them, while dissociative
disorders seem to occur without any clear physical causes.
Answers to Your Brain and Behaviour Questions (p. 312)
1. Imagine a person who has witnessed a bank robbery. Provide an example of a leading
question that might alter this person’s memory and a non-leading question that is more likely
to preserve the original memory. Many correct answers are possible. One example of a
leading question is, “Wasn’t the perpetrator wearing brown dress shoes?” An example of a
non-leading question is, “Can you describe what the perpetrator was wearing?”
2. Explain how the visual cortex is activated differently when a person is remembering a
witnessed event accurately versus inaccurately. Association areas of the visual cortex are
active regardless of whether the memory is being recalled accurately or inaccurately. But the
primary visual cortex is only active when the memory is being recalled accurately.
3. Discuss the role of the prefrontal cortex and the hippocampus in the storage and recall of
eyewitness memory. The hippocampus allows new memories to be formed and sent to other
areas of the brain for storage. The prefrontal cortex allows memories to be stored, retrieved,
and stored again.