Chapter 7: Attention and Memory
Henry Molaison (HM) had uncontrolled seizures, the anticonvulsive drugs at the time couldn’t
Underwent surgery, removed parts of his medial temporal lobes, including hippocampus.
Seizures were quieted, but lost ability to form new long term memory.
Short term memory was intact but it could not be transformed to long term memory. Brenda
Miller studied him for 40 years, Tracing Task: his performance improved gradually, proving he
could retain some information.
Memory: The nervous system’s capacity to acquire and retain usable skills and knowledge.
(incomplete, biased and distorted)
How does attention determine what is remembered?
Look and Listen commands that direct attention. To get info into memory person needs to
attend “Pay attention”
Visual Attention is Selective and Serial (Anna Treisman)
We automatically identify “primitive” features, such as color, shape, orientation, and
movement. Separate systems analyze objects’ different visual features.
Parallel Processing: Allows us to process info from different visual features at the same time by
focusing on targets over distracters.
Treisman’s visual search tasks (feature search tasks) participants search for targets that differ
from the others in only one feature. Other objects on screen are called distracters.
Searching for a single feature, such as a red stimulus, is fast and automatic, searching for two
features is serial -> you need to look at the stimuli one at a time) and effortful ( takes longer and
requires more attention.
Conjunction Task: The stimulus you are looking for is made up of two simple features.
Auditory Attention Allows Selective Listening
Attention is limited; it is hard to perform two tasks at the same time, esp. if you rely on the
1953 psychologist E.C. Cherry Cocktail Party Phenomenon: you can focus on a single convo in
the midst of a party, yet a pertinent stimulus, like hearing your name in another convo, or jucy
gossip can capture your attention.
Cherry developed selective listening studies to examine what people’s minds do with
unattended info when people pay attention to one task.
His developed Shadowing: Participant receives a different auditory messages in each ear, but is
required to repeat (“shadow”) only one.
Some info goes through the filter of attention eg: hearing your name, or the name of someone
familier. Selective Attention Can Operate at Multiple Stage of Processing
1958 Psychologist Donald Broadbent developed filter theory to explain selective nature of
Attention is like a gate that opens for important info and closes for irrelevant info.
Some stimuli demand attention and shut off the ability to attend to anything else.
Faces are good example of stimuli that capture attention provide social info such as potential
mate or potential danger.
Threats are prioritized over less meaningful stimuli by the attention system.
Decisions about what to attend to are made early in the perceptual process, but other studies
reveal unattended info is processed at least to some extent.
Selective-listening studies have found that even when participants cannot repeat an unattended
message, they still have processed its contents.
Change Blindness: The common failure to notice large changes in the environment.
o Shows large discrepancies exist between what people believe they see and what they
actually see. Shows how attention influences memory.
What are the Basic Stages of Memory?
In late 1960s psychologists thought memory processing is analogous to computers info
processing. Memory’s multiple processes operate in 3 phases:
o Encoding Phase: occurs at time of learning, as info is encoded or changed into neural
code that the brain can use.
o Storage Phase: Can last a sec to a lifetime (there are 3 storage systems; they differ in
how long they store information.)
o Retrieval Phase: Act of recalling or remembering stored information to use it.
Atkinson and Shriffin’s Model Memory Model: The three-stage memory system that involves
Memory is a three part system that involves: Sensory Memory, Short-Term (working memory)
The model is somewhat inaccurate and incomplete, vocabulary from it remain widely used
A: Information Processing Model
1.Encoding 2.Storage 3. Retrieval
Sensory Info is acquired and Info is stored in brain (just Info is retrieved when it is
processed into neural code as it is stored in a needed (just as it shows up
(just as info is entered with computer’s hard drive) on screen to be viewed)
B: Modal Memory Model Maintenance
Sensory 1.Sensory Memory 2.Short Term Memory 3. Long Term Memory
input Unattended info is lost Attention Unattended Encoding Some info may be lost
rehearsed info is lost over time
Retrieval Sensory Memory Is Blind
Sensory Memory: Memory for sensory information that is stored briefly close to its original
A sensory memory occurs when a light, a sound, an odor, a taste, or a tactile impression leaves a
vanishing trace on the nervous system for a fraction of a second.
o When someone says, “ You are not paying attention to me,” you can often repeat back
the last few words the person spoke even of you were think of something else. (Dolder)
1960 Cog Psy. George Sperling provided initial empirical support for sensory memory.
o His experiment: 3 rows of letters were flashed on screen 1/20 of second. Most people
believed they had seen all the letters, but could recall 3 or 4. The time it took them to
name the first 3 or 4, they forgot the others.
o Participants very quickly lost their memories of exactly what they had seen. Tested this
hypothesis by showing the same letters, but signaling a H (top row), M (Middle row),
and L (bottom row) pitched sound as soon as the letters disappeared. Now people were
able to tell almost all of the letters. But this correlated with the delay between the
letters’ disappearance and the sound.
o Conclusion: Visual Memory for ~1/3 sec, after which the sensory memory trace faded
progressively until it was no longer accessible.
Our sensory memories allow us to experience the world as a continuous stream rather than in
discrete sensations. (Like a motion picture: movie)
Working Memory is Active
Info attended to is passed from sensory stores to Short-Term Memory (STM): A limited capacity
memory system that holds info in awareness for a brief period, but longer than sensory memory
This short term system also called Working Memory(WM): to indicate it is a memory(storage)
system that combines info from different sources and can work on the info we have in memory.
Also called Immediate Memory: consists of our fleeting thoughts, ever-shifting feelings, and
temporary impressions of things in the world. Analogous to the RAM.
Info remains in the WM for 20 to 30 seconds, then disappears until you actively prevent that
from happening by thinking about or rehearsing the information.
Memory Span and Chunking
WM can hold a limited amount of information.
Cognitive psychologist George Miller said the limit is generally 7±2, a figure referred to as
memory span. Some intelligence tests use memory span as a measure of IQ.
Chunking: Organizing information into meaningful units to make it easier to remember.
o Master chess players can reproduce exact arrangement of pieces moments later.
The greater your expertise with the material, the more efficiently you can chunk information,
and therefore the more you can remember.
Updating of old WM; retrieval, transformation, and substitution -> eg: 20+5=25 Sometimes only one of them is needed: substitute 20 with 25. No need for retrieval &
Working Memory’s Four Parts
Baddeley’s Working Memory System: Four components of working memory: the central
executive, the phonological loop, the visuospatial sketchpad, and the episodic buffer
Central Executive(Control System): Encodes info from the sensory systems, then filters and
stores in long term memory. Also retrieves information from long term when needed.
Central Executive relies on the 3 sub-components which temporarily hold auditory or
visuospatial info or personally relevant info.
Phonological Loop (Rehearsal): Encodes auditory info and is active when person tries to
remember words by reading them, speaking them or repeating them
o Inner Voice reads along as your eyes process written material.
o Recall is poorer when words on a list sound the same than when they sound
o Words are processed by WM by how they sound than by how they look or what
Visuospatial Sketchpad (Rehearsal): Processes visual information, such as object’s features
and where they are located.
Episodic Buffer: Holds temporary information about oneself, drawing heavily on long term
Long Term Memory is relatively permanent: Human LTM is nearly limitless
Distinguishing Long Term Memory from Working Memory
Differ by duration and capacity.
Serial Position Effect: better recall of items early or late in the list relative to items in the middle
of the list. Involves two separate effects:
o Primary Effect is due to LTM: better memory people have for items presented at the
beginning of the list
o Recency Effect is due to WM: people’s better memory of the most recent items, items
at the end of the list.
Henry .M had a normal WM as he was able to keep convo as long as he was not interrupted and
a normal LTM up to the surgery. After surgery he is unable to turn WM to LTM.
28 year old accident victim damaged left temporal lobe which damaged his WM, but was normal
WM and LTM are highly interdependent on each other: eg to chunk info in WM we need to
make meaningful connections form info stored in LM.
What gets into long term memory?
Information enters permanent storage through rehearsal. Overlearning: rehearsing info you know pretty well leads to improved long term memory.
Distributed Practice: material studied in multiple sessions over time; remembered better
Massed Practice: Brief period; cramming
Sometimes rehearsing countless time just doesn’t cut it.
We attend just enough for the task at hand and lose info that seems irrelevant.
Only info that helps us adapt to our environment is typically transformed into long term
Evolutionary theory explains how we decide in advance what info will be useful for assistance in
reproduction and survival. Learning/knowledge from past experiences
What re the Different Long Term Memory Systems?
Memory is not just one entity but a process that involves several interacting systems.
Riding a bike doesn’t require conscious effort, purposely trying to remember something requires
conscious effort to get info from LTM.
Explicit memory involves conscious effort
We all have memories about which we have no conscious knowledge
Implicit Memory: system underlying unconscious memories. (HM mirror tracing exercise)
Explicit Memory: Processes we use to remember info that we can say we know. Eg recall what
you had for dinner last night, how to spell a word.
Declarative Memory: Cognitive info retrieved from explicit memory; knowledge that can be
declared (consciously brought to mind). Involves words, concepts, images. Exams test
Explicit Memory divided into episodic and semantic memory
Episodic Memory: person’s past experiences and info about the time and place the experience
occurred. Eg remembering what happened on your 14 Birthday
Semantic Memory: represents knowledge of facts about the world, independent of personal
experience. We might not remember when or where we learned it. Eg. Capitals of countries.
Case of group of British Children: their episodic memory was damaged; couldn’t remember
what they had for lunch, what they had just watched on TV. But their Semantic Memory (facts)
was intact therefore falling in normal range in IQs.
Implicit Memory Occurs without Deliberate Effort
Unknowingly you have instructions to run and catch a ball (implicit memory); happens
automatically without deliberate effort. Daydreaming while driving (no episodic memory of the
past few minutes), implicit memory of how to drive has kicked in.
Classical conditioning uses implicit memory.
Advertisers use implicit memory, constant exposure to brands False Fame Effect: On day1 participants read a bunch of names. On day 2 were asked to read a
list of names and decide if each person was famous or not. Students misjudged some of the
made up names from day 1 as those being famous. This is because of implicit memory.
Implicit memory is also involved in Repetition Priming: the improvement in identifying or
processing a stimulus that has been experienced previously. Eg app___ che____ pat___
Procedural Memory/Motor Memory (Implicit Memory): Involves motor skills and behavioral
habits. Procedural memories have an automatic, unconscious aspect, sometimes people find
that consciously thinking about automatic behaviors interferes with smooth production of those
behaviors. Eg driving, biking, playing ball
Prospective Memory is remembering to do something
Prospective Memory: remembering to do something at some time in the future.
Remembering to do something takes up valuable cognitive resources, either by reducing # of
items we can deal with in WM or by reducing #of things we can attend to.
Prospective memory involves automatic (without conscious effort or intent) and controlled
Automatic-> seeing something triggers your