PSY100
ATTENTION AND MEMORY
[CHAPTER 7]
Henry Molaison (H.M.): Underwent a surgery for his sever epilepsy. He got his medial
temporal lobes, including hippocampus, removed in hopes of stopping the seizures.
However from this surgery, he lost the ability to form new long term memories. The
only memories he had were the ones that he knew at the time of the surgery
(childhood, members of his family, etc). He was able to learn new things and acquire
knowledge, but not remember it or remember doing it.
Memory: The nervous system’s capacity to acquire and retain useable skills and
knowledge.
How does attention determine what is remembered?
Visual Attention is Selective and Serial
- According to Treisman’s theory about attention, we automatically identity
“primitive” features such as colour, shape, orientation and movement, within an
environment.
o Separate systems analyze objects’ different visual features; through
parallel processing, these systems all process information at the same
time, and we can attend selectively to one feature by effectively blocking
the further processing of the others
o Visual research task: consisted of a target (red) along with distractors
(many black)
o Serial: searching for 2 features (you need to look at stimuli one at a time)
Effortful: takes longer and requires more attention
Conjunction task: stimulus you are looking for is made up of two
simple features
Auditory Attention Allows Selective Listening
- Because attention is limited, it is hard to perform two tasks at once, especially if
they rely on the same mechanisms
Cocktail party phenomenon:
- Can focus on a single conversation in a chaotic cocktail party, but a pertinent
stimulus like hearing you name mentioned in another conversation or hearing
gossip, can capture your attention
o Your selective attention can also determine which conversation you hear
- Shadowing: selective-listening studies to examine what peoples minds do with
the unattended information when people pay attention to one task o When given different auditory messages in each ear, and asked to repeat
just one (“shadow”)
o The subject usually notices the unattended sound (the message given in
the other ear) but will have no knowledge about its content
Selective Attention Can Operate at Multiple Stages of Processing
- Filter theory: People have a limited capacity for sensory information and thus
screen incoming information, letting in only the most important
- Some stimuli such as those that evoke emotions, may capture attention because
they provide important information about potential threats in an environment
o Same object produces a stronger attentional response when it is viewed
as socially relevant (eg, if someone is a potential mate) or may intend to
cause physical harm (angry face)
o Found that faces, especially when threatening, are prioritized over less
meaningful stimuli by the attentional system
- Studies have found that even when participants cannot repeat an unattended
message, they still have processed its content consciously
- Change blindness: the common failure to notice large changes in environments
o Shows that we can attend to a limited amount of information and that
large discrepancies exist between what most people believe they see and
what they actually see
o Shows how attention influences memory
o Therefore our perceptions of the world are often inaccurate, and we
have little awareness of our perceptual failures; we simply do not know
how much info we miss in the world around us
What are the basic stages of memory?
- Memory allows us to take info from our experiences and store it for retrieval
later
- Memory’s 3 distinct phases
o Encoding phase: processing of info so that it can be stored
o Storage phase: the retention of encoded representations over time that
corresponds to some change in the nervous system that registers the
event
o Retrieval phase: the act of recalling or remembering stored info to use it
- Modal memory model: the 3 stage memory system that involves sensory
memory, short-term memory, and long-term memory
Sensory memory is brief
- Memory for sensory info that is stored briefly close to its original sensory form
- We obtain info about the world through our senses which then take that info
and change it into neural impulses; everything that we remember is the result of
neurons firing in the brain - Sperling concluded that the visual memory persisted for about 1/3 of a second,
after which the sensory memory trace faded progressively until it was no longer
accessible
Working memory is active
- Short term memory (STM): A limited-capacity memory system that holds info
in awareness for a brief period
o Working memory (WM): An active processing system that keeps
different types of info available for current use
o Also called immediate memory, or RAM (random access memory), which
can handle only a small amount of info compared with the vast amount
stored
Memory span and chunking
- Memory span: Miller noted that the limit to WM is generally 7 items (plus or
minus two)
- More recent research says its actually 4 items
- Chunking: organizing info into meaningful units to make it easier to remember
- The 3 processes – retrieval, transformation, and substitution- make distinct and
independent contributions to updating the contents of working memory
(sometimes only need one/two of the processes to update working memory)
Working memory’s four parts
- WM is an active processing unit that deals with multiple types of information,
such as sounds, imagers, and ideas
- Working memory components: central executive, phonological loop, visuospatial
sketchpad, and episodic buffer
- Central executive: presides over the interactions among the phonological loop,
the visuospatial sketchpad, the episodic buffers and long term memory
o It is the control system; encodes info from sensory systems and then
filters info that is important to be stored in long term memory
- Phonological loop: encodes auditory info and is active whenever a person tries
to remember words by reading them, speaking them or repeating them
- Visuospatial sketchpad: processes info such as objects’ features and where they
are located
o Patients with brain damage find it hard remembering spatial layouts but
have little difficulty remembering words, or vice versa
- Episodic buffer: holds temporary info about oneself, drawing heavily on long
term episodic memory
Long-term memory is relatively permanent
- The relatively permanent storage of info
Distinguishing long-term memory from working memory
- In two ways: duration and capacity
- Serial position effect: the ability to recall items from a list depends on order of
presentation, with items presented early or late in the list remembered better
than those in the middle o Involves two separate effects: primacy effect (refers to the better
memory people gave for items presented at the beginning of the list- due
to LTM) and recency effect (refers to peoples better memory for the last
most recent items- due to WM)
What gets into long-term memory
- Possible explanations:
o Info enters permanent storage through rehearsal (showed that
overlearning, where you keep rehearsing info you already know leads to
improved memory over longer periods of time – distributed practice,
whereas through massed practiced or cramming)
o We attend just enough attention for the task at hand and lose info that
seems irrelevant
o Only info that helps us adapt to our environment is typically transformed
into a long-term memory
o Evolutionary theory helps explain how we decide in advance what
information will be useful
What are the different long-term memory systems?
- Most basic distinction between memory systems is the division of memories we
are consciously aware of from memories we acquire without conscious effort or
intention and do not know we know
- Implicit memory: the system underlying unconscious memories
- Explicit memory: the process involved when people remember specific info
o Episodic memory: memory for one’s personal past experiences
o Semantic memory: memory for knowledge about the world
- Declarative memory: the cognitive info retrieved from explicit memory;
knowledge that can be declared through words/concepts &/or visual images
Implicit memory occurs without deliberate effort
- Not able to put memory into words
- Example would be classical conditioning, because you experience fear at sight of
person in white lab coat but might have past associations between a person in
white lab coat and pain
- At social level of analysis, implicit attitude formation can affect our beliefs about
people, such as whether particular people are famous
- False fame effect: if all you remember about a name is that you have heard it
before or it feels familiar, you will likely assume it belong to a famous person (if
were given a list of famous people the day before)
- Implicit memory is involved in repetition priming: the improvement in
identifying or processing a stimulus that has been experienced previously
- Procedural memory: a type of implicit memory that involves motor skills and
behavioural habits employed to achieve goals
o Have automatic and unconscious aspect
Prospective memory is remembering to do something - Prospective memory: remembering to do something at some time in the future
o Takes up valuable cognitive resources, either by reducing number of
items we can deal with in WM or by reducing the number of things we
can attend to
o Involves automatic and controlled processes
How is information organized in long-term memory?
Long-term storage is based on meaning
- We have mental representations for complex and abstract ideas, including
beliefs and feelings such as love
- All this info is stored in networks of neurons in the brain
- Memories represent many different kinds of info whether images, facts, ideas,
tastes or muscle movements
- Retrieval often involves an explicit effort to access the contents of memory
storage
- Levels of processing model: the more deeply an item is encoded, the more
meaning it has and the better it is remembered
- Maintenance rehearsal: repeating the item over and over
- Elaborative rehearsal: encodes the info into more meaningful ways, such as
thinking about the item conceptually or deciding whether it refers to oneself
Schemas provide an organizational framework
- Schema: a hypothetical cognitive structure that helps us perceive, organize,
process and use info
o Help us sort out incoming info, and guide our attention to an
environments relevant features
o We construct new memories by filling in holes within existing memories,
overlooking inconsistent info, and interpreting meaning based on past
experiences
- Can lead to biased encoding because culture heavily influences schemas
Information is stored in association networks
- Network of associations: similar concepts are connected through their
associations
- Node: each unit of info in a network
o The closer the nodes, the stronger the association will be
o Each node connected to many other nodes
o Activating one node increases the likelihood that closely associated
nodes will also be activated
- Associative networks’ overall organization is based on hierarchically structured
categories, which provide a clear and explicit blueprint for where to look for
needed info
Retrieval cues provide access to long-term storage - Retrieval cue: anything that helps a person (or another animal) recall info from
memory
- It is easier to recognize than to recall info
Encoding specificity
- Encoding specificity principle: any stimulus that is encoded along with an
experience can later trigger memory for the experience
- Context dependent memory: when the recall situation is similar to the encoding
situation
o Can be based on thing such as physical location, odors, background
musi
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