CHAPTER 8. Memory
Memory refers to the processes that allow us to record and later retrieve experiences
People with Amnesia, or memory loss can discuss his childhood, teens but has
forgotten some events that occurred within the two years, and has lost the ability to
form new memories.
MEMORYAS INFORMATION PROCESSING
Encoding refers to getting information into the system by translating it into a neural
code that your brain processes.
Storage involves retaining information over time. Once in the system, information
must be filed away and saved.
Retrieval is the way to pull information out of storage when we want to use it.
Encoding, storage, and retrieval represent what our memory system does with
Memory has three major components:
(1) sensory registers, which detect and briefly hold incoming sensory information;
(2) working memory, which processes certain information received from the sensory
registers and information retrieved from long-term memory;
(3) long-term memory, which stores information for longer periods of time.
Sensory memory holds incoming sensory information just long enough for it to be
recognized. It is composed of different subsystems, called sensory registers, which
are the initial information processors.
Our visual sensory register is called the iconic store. Iconic memory stores complete
information for only a fraction of a second, the image would quickly vanish.
The echoic store is the auditory sensory register.
Echoic memory lasts longer than iconic memory.Anearly complete echoic trace
may last about two seconds and a partial trace may linger for several more.
Short-Term/Working Memory Short-term memory also is referred to as working memory, because it consciously
processes, codes, and “works on” information
Memory codes. Once information leaves sensory memory, it must be represented by
some type of code if it is to be retained in short-term and eventually long-term
We may try to form a mental image (visual encoding), code something by sound
(phonological encoding), or focus on the meaning of a stimulus (semantic encoding).
For physical actions, such as learning sports or playing musical instruments, we code
patterns of movement (motor encoding).
e.g. You use phonological codes (saying the words silently to yourself) and, as you
think about the material, semantic codes that represent their meaning when you read
these words (visual stimuli)
e.g. They might recall a V instead of a B because of the similarity in how the letters
sound. Because phonological codes play an important role in short-term memory.
Short-term memory can hold only a limited amount of information at a time. Most
people can hold no more than five to nine meaningful items in short-term memory.
Most people can recall a maximum sequence of five to nine digits.
8 3 5 2
4 3 9 3 1
7 1 4 9 3 7
5 4 6 9 2 3 6
The limit on short-term memory capacity concerns the number of meaningful units
that can be recalled.
Chunking: Combining individual items into larger units of meaning helps recall.
Maintenance rehearsal: Simple repetition of information
e.g. When you look up a telephone number and keep saying it to yourself,
Elaborative rehearsal involves focusing on the meaning of information or relating it
to other things we already know. e.g. by thinking about examples of iconic memory in your own life.
Both are under short-term memory, but elaborative rehearsal is more effective in
transferring information into long-term memory
Baddeley divides working memory into 4components.
First, maintain some info in an auditory working memory
e.g. You repeat a phone number, name, or new vocabulary terms to yourself mentally.
Asecond component, visual-spatial working memory (the “visuospatial sketchpad”),
allows us to temporarily store and manipulate images and spatial information
e.g. forming mental maps of the route to some destination.
Athird component, the episodic buffer, provides temporary storage space where
information from long-term memory and from the phonological loop and/or
visuospatial subsystems can be integrated, manipulated, and made available for
e.g. after reading or hearing me say, “How much is 87 plus 36?” your phonological
loop initially maintains the acoustic codes for the sounds of 87 and 36 in working
Your visuospatial sketchpad also might maintain a mental image of the numbers.
This creates the ingredients for the conscious perceptions that you experience as you
perform the mental addition (e.g., “7 + 6 = 13, carry the 1 …”). The episodic buffer
also comes into play when you chunk information.
Finally, a control process, called the central executive, directs the action. It decides
how much attention to allocate to mental imagery and auditory rehearsal, calls up
information from long-term memory, and integrates the input. Research suggests that
the prefrontal cortex, the seat of “executive functions” is heavily involved in
directing the processing of information in working memory
Long-term memory is our vast library of more durable stored memories. . Long-
term storage capacity essentially is unlimited. Once formed, a long-term memory can
endure for up to a lifetime
Serial position effect is a U-shaped pattern that recall is influenced by a word's
position in a series of items. The serial position effect has two components, a
primacy effect, reflecting the superior recall of early words, and a recency effect,
representing the superior recall of the most recent words.
Even a short delay of 30 seconds in recall (during which rehearsal is prevented) eliminates the recency effect.
The first few words enter short-term memory, we can quickly rehearse them and
transfer them into long-term memory
Effortful processing, encoding that is initiated intentionally and requires conscious
e.g. Rehearsing, making lists, and taking class notes
Automatic processing, encoding that occurs without intention and requires minimal
e.g. Information about the frequency, spatial location, sequence, and timing of events
often is encoded automatically
Which group of words will be recognized most easily: those processed structurally,
phonologically, or semantically?
Semantic(focus on the meaning of information)- structural (e.g., capitalized versus
lowercase) shallow processing- phonemically encoding words is intermediate.
Even thousands of shallow exposures to a stimulus do not guarantee long-term
Elaborative rehearsal focuses on the meaning of information- involves deeper
processing than maintenance rehearsal and should be more effective in transferring
information into long-term memory.
An organizational scheme can enhance the meaningfulness of information and also
serve as a cue that helps to trigger our memory
e.g. FIC as Fraser...
Hierarchical tree (breaking down as layers)
Chunking refers to combining individual items into a larger unit of meaning.
Acronyms combine one or more letters (usually the first letter)
e.g. “colours of the rainbow” (red, orange, yellow, green, blue, indigo, violet).
e.g. How many windows are there in your home?
-Try to construct and scan a series of mental images in your working memory, based
on information that you draw out of long-term memory. Paivio proposes that information is stored in long-term memory in two forms: verbal
codes and non-verbal (typically visual) codes. According to his dual coding
theory. In short, two codes are better than one
Abstract concepts are easier to encode semantically than visually.
Aschema is a “mental framework”—an organized pattern of thought about some
aspect of the world
Schemas create a perceptual set, which is a readiness to perceive—to organize and
interpret—information in a certain way.
e.g. a class of people, events, situations, or objects
e.g. Your schema—your mental framework for “washing clothes”—helps you
organize these ideas and recall a great deal more.
Schemas, Encoding, and Expertise
The relation between expertise, schemas, and encoding in a classic study.
e.g. You have used language for most of your life and have years of experience about
how the world works
Associative network shows what a small portion of such a network might be like.
Iitems within the same category—types of flowers, types of fruits...—generally have
the strongest associations and therefore tend to be clustered closer together.
In a neural network, each concept is represented by a particular pattern or set of
nodes that becomes activated simultaneously. Neural network models are often called
parallel distributed processing models (PDP).
TYPES OF LONG-TERM MEMORY
Declarative memory involves factual knowledge, and includes two subcategories
Episodic memory is our store of factual knowledge concerning personal
experiences: when, where, and what happened in the episodes of our lives.
e.g. I ate pizza last night is an episodic memory.
Semantic memory represents general factual knowledge about the world and
language, including memory for words and concepts.
e.g. Mt. Everest is the world's tallest peak Episodic and semantic memories are declarative; their contents can be verbalized.
Procedural memory is nondeclarative; its contents cannot readily be verbalized.
In contrast to declarative memory, whose contents are verbalized, procedural memory
(nondeclarative memory) is reflected in skills and actions. Classically conditioned
responses also reflect procedural memory
e.g. typing, riding a bicycle, or playing a musical instrument.
Explicit memory involves conscious or intentional memory retrieval
e.g. short-answer, and fill-in-the-blank questions involve recall or cued recall.
Implicit memory occurs when memory influences our behaviour without conscious
e.g. Riding a bicycle or performing any well-learned skill.
Associative network models view long-term memory as a network of associated
nodes, with each node representing a concept or unit of information. Neural network
models propose that each piece of information in memory is represented not by a
single node but by multiple nodes distributed throughout the brain. Each memory is
represented by a unique pattern of simultaneously activated nodes.
Declarative long-term memories involve factual knowledge and include episodic
memories (knowledge concerning personal experiences) and semantic memories
(facts about the world and language). In contrast, procedural memory is reflected in
skills and actions. Explicit memory involves conscious or intentional memory
retrieval, whereas implicit memory occurs when memory influences our behaviour
without conscious awareness.
Priming shows how a retrieval cue (“fire engine,” “MO”) can trigge