CHAPTER 7 – ATTENTION AND MEMORY
- Memory: the nervous system’s capacity to acquire and retain usable stills and knowledge.
- H.M. suffered from severe epilepsy (seizures are uncontrolled random firings of groups of
neurons; can spread across the brain) originating in temporal lobes; doctors removed parts of
medial temporal lobes, including hippocampus.
• Lost ability to form new long-term memories, but was able to learn new motor tasks. (ex: drawing
a star, while looking at another object).
ATTENTION DETERMINES WHAT IS REMEMBERED
- We automatically identify “primitive” features (color, shape, orientation and movement) within
environment. (Finding your friend wearing a red shirt, in a crowd of people wearing black shirts)
- Parallel Processing: allows us to process information from different visual features at the same
time by focusing on targets over distracters (e.g. a red object in the midst of black objects).
• In visual/feature search tasks studies, people look at display of diff objects on screen and search
for targets which differ from the others in only one feature.
- Features like color, size, motion, orientation pop out when targets differ from distracters.
- Searching for single feature is fast and automatic but searching for two features is serial (need to
look at stimuli one at a time) and effortful (takes longer); e.g trying to find objects both blue and
square among many.
- Talking on cellphone, even hands-free cellphone, while driving more hazardous than talking w/
passenger in the car; person talking to driver on phone does not know what’s happening but driver
talking to passenger can signal that conversation needs to pause as situations demand.
- Cocktail Party Phenomenon: a pertinent stimulus (like hearing your name) at chaotic cocktail
party will capture your attention (proximity and loudness may affect what you will attend to but
your selective attention can determine what conversation you hear).
- In selective-listening studies, researchers can use shadowing, in which participant receives
different auditory messages in each ear but is required to repeat (“shadow”) only one; the subject
notices the unattended sound but has no knowledge of content.
- Filter Theory: assumes that people have a limited capacity for sensory information and thus
screen incoming information, letting in only the most important; attention is a “gate” that opens for
important info, closes for irrelevant info.
• Some stimuli, like those that evoke emotions, readily capture attention b/c they provide
important info about potential threats in environment.
• Same object produces stronger attentional response when it is viewed as socially relevant
(e.g. an eye) than when it viewed as nonsocial (e.g. arrowhead).
• Faces capture attention b/c they provide important social info (e.g. whether someone is
• Faces, esp. when threatening, are prioritized over less meaningful stimuli by attentional
- Studies show that unattended info is process at least to some extent; in selective-listening studies,
even when people cannot repeat unattended words, those presented with “river” interpreted same
attended message differently than people presented with “monkey”.
- Change Blindness: the common failure to notice large changes in environments.
• Half of people in studies giving directions to stranger never noticed they were talking to diff
person when stranger is changed as long as replacement is the same race and sex.
• Shows we can attend to limited amount of info and shows how attention influences memory. - Change Blindness Blindness: people’s unawareness that they often do not notice obvious
changes to environment (people believe that they always notice large changes b/c people often do
not find out about the things they failed to perceive).
BASIC STAGES OF MEMORY
(2) Storage (3) Retrieval
Information Information Information is
Processing (1)Encoding is stored in retrieved when
Model: Information is acquired and brain (e.g. needed (e.g.
(analogous to processed in to neural code stored on shows up on
computers) (e.g., information entered on computer computer screen).
- Sensory Memory: memory for sensory information that is stored briefly close to its original
sensory form; we are not aware that it is operating.
- Occurs when light, sound, odor, taste or tactile impression leaves vanishing trace on the nervous
system for a fraction of a second.
- In Sperling’s experiment, people looked at a screen on which three rows of letters flashed for
1/20th of second; tones were sounded at different intervals after letters displayed (e.g. 0.15 sec
after, 0.30 sec after, etc.) for people to recall the letters in each row (different tones for different
rows); the longer the delay b/w disappearance of letters and tone, worse the participants recalled
• Sensory memory persists for about 1/3 of a second and progressively fades
- Sensory memory allow us to experience world as continuous (keeps information long enough to
connect one image with the next).
- Short-Term Memory (STM)/ IMMEDIATE MEMORY: limited-capacity memory system that
holds information in awareness for brief period (but longer than the fraction of second that
sensory memory lasts). (EX: REMEMBERING A PHONE NUMBER)
• The short-term memory system is Working Memory (WM): an active processing system that
keeps different types of information available for current use (aka. Immediate memory). • Analogous to Random-access memory (RAM) in computers
- Information remains in WM for 20-30 seconds then disappears unless you actively prevent that
from happening by thinking about or rehearsing the information.
- George Miller (cognitive psychologist) said that WM can hold 7 ±2 items; called Memory Span;
recent-research says WM may be limited to four items.
• Items can be letters/groups of letters, groups of numbers, words, concepts
- Chunking: organizing information into meaningful units to make it easier to remember; more
efficiently you chunk, the more you can remember (meaningful units more easy to remember than
- WM is updated by three processes: retrieval, transformation and substitution.
• Sometimes only one of processes in necessary to update WM (e.g. to transform 25 to 20,
person may not have to retrieve 20, just substitute new number into WM).
- Central Executive encodes information from sensory systems then filters important info to be
stored in long-term memory; retrieves information from long-term memory as needed.
- Phonological loop encodes auditory information and is active when person tries to remember
words by reading them.
• People tend to make errors when trying to remember consonants w/ consonants that sound
similar (like D & T) rather than those that look similar (like Q & D).
• Recall is poorer when words on list sound the same than when they sound dissimilar but related in
meaning; words processed in WM by how they sound rather than how they look or what they
- Visuospatial Sketchpad processes visual info and where they are located (e.g. allows you to keep
track of where a dog is and whether you need to be aware of the dog during dog walking).
- Patients may have difficulty remembering words (phonological) but may be good at remembering
spatial layouts (visuospatial); shows WM is more than all-inclusive storage system.
- Episodic buffer hold temporary information about oneself and draws heavily on long-term
- Long-Term Memory: relatively permanent storage of information (analogous to computer hard-
drive); LTM is nearly limitless.
- Different from WM in duration and capacity.
- Evidence that LTM and WM are separate systems come from studies where people recalled long
list of words; demonstrated serial position effect. - Serial Position Effect: the ability to recall items from a list depends on order of presentation –
items presented early or late in list is remember better than those in middle.
Primary Effect: better memory people have for items at the beginning
• Recency Effect: better memory people have for most recent items (end of list)
• Relies on distinction b/w LTM and WM: earliest items are transferred to LTM b/c people
rehearse early items the most; the last few items are still in WM when participants have to
recall items immediately.
When there is delay b/w presentation of list and recall task, it interfered w/ recency effect but
not primary effect.
- For H.M.,WM system was perfectly normal (able to keep track of conversation as long as he was
actively involved) and much of LTM intact (remembered events before surgery) but unable to
transfer new information from WM into LM.
- To chunk information in WM, people need meaningful connections based on info from LTM.
- What gets into LTM: (LIMITED TO FOUR CHUNKS)
• Information may enter LTM through rehearsal (e.g. memorizing lines for actors); over learning
(keep rehearsing material you know really well) leads to improved memory.
• Distributed practice (material studied in multiple sessions over time) leads to better memory than
massed practice (cramming).
• Information that is familiar, seen countless times, may not get into LTM (e.g. penny experiment);
we attend just enough for task at hand and lose irrelevant info; only info that helps us to adapt to
environment is typically transferred through LTM.
Long-Term Memory Systems
- Memory is not just one entity but a process that involves several interacting mechanisms.
(University of Toronto - Research on human memory)
- Processes involved when people remember specific information (acquired w/ conscious effort).
• The cognitive information retrieved in explicit memory is declarative memory: knowledge
that can be declared/consciously brought to mind.
• E.g. recalling what you ate for dinner last night, exam tests declarative memory.
- Explicit memory can be divided into episodic and semantic memory:
• Episodic Memory: refers to personal past experiences.
• Semantic Memory: knowledge of facts independent of personal experience (e.g. knowing the
capital of country we never visited).
• Children w/ poor memory for episodic info had trouble remembering what they ate for lunch
but remembered many facts like who Martin Luther King Jr. was (can retrieve semantic
- Consists of memories without awareness of them; not able to put the memories into words;
classical conditioning in learning employs implicit memory.
- Does not require conscious attention and happens automatically w/o deliberate effort.
• E.g. daydreaming while driving; you employ implicit memory not to crash/go in wrong
• Attitudes influenced by implicit learning (e.g. exposure to brand names make us more likely to
think of them)
- False Fame Effect: when research participants given a list of made-up names and, the day after,
told to read a list of names and determine who was famous, some misjudged some made-up
names as being famous people b/c they were familiar.
- Implicit memory involved w/ Repetition Priming: improvement in identifying or processing a
stimulus that has been experienced previously. • Study participants counted letters in words appearance, chestnut etc., when asked to
complete the stems app___, che___, more likely to choose words they encountered even
when they could not recall explicitly the words in first task.
- Procedural Memory (Motor Memory): involves motor skills, habits, behaviors employed to
achieve goals like coordinating muscle movements to ride bicycle (automatic and unconscious).
- Remembering to do something at some time in the future. (future oriented)
- Reduces the number of items we can deal with in working memory or reduces the number of
things we can pay attention to.
- Involves both automatic and controlled processes: retrieval cues may occur in environment (e.g.
seeing something makes you remember to do something) but environment may not have obvious
retrieval cues; might require ongoing remembering or sticky notes.
ORGANIZATION OF INFORMATION IN LONG-TERM MEMORY
- Memories are stored mental representations: e.g. the concept of “dog” is a mental representation
for a category of animals w/ similar features.
- Retrieval is involved in explicit and implicit memory systems (trying to remember your 5th
birthday, or w/o effort like instantly remembering name of an acquaintance).
- Long-term storage is based on meaning:
- 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: encoding information in meaningful ways (e.g. thinking about item
conceptually, making connections to oneself); link it to knowledge from LTM.
- In studies, the words processed at the deepest level, based on semantic meaning, were
remembered the best, compared to words remembered by what it looked like or how the word
• Semantic encoding activated more brain regions than shallow encoding; greater brain activity
= better memory
- Structures in long-term memory that help us perceive, organize, process and use information;