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					Psychological Science, 3rd Edition
                      Michael Gazzaniga
                       Todd Heatherton
                          Diane Halpern
Attention and
     Memory

           7
      Questions to Consider:
How Does Attention Determine What Is Remembered?

What Are the Basic Stages of Memory?

What Are the Different Long-Term Memory Systems?

How Is Information Organized in Long- Term Memory?

What Brain Processes Are Involved in Memory?

When Do People Forget?

How Are Memories Distorted?

How Can We Improve Learning and Memory?
How Does Attention Determine
What Is Remembered?
   Visual Attention Is Selective and Serial
   Auditory Attention Allows Selective
    Listening
   Selective Attention Can Operate at
    Multiple Stages of Processing
   Critical Thinking Skill: Recognizing When
    “Change Blindness Blindness” May Be
    Occurring
Learning Objectives
Explain how attention is
 adaptive.

Explain why we can be blind to
 many changes in our
 environments.
The portions of the medial temporal lobe that were removed from H.M.’s brain are indicated by the
shaded regions.
Visual Attention Is Selective
and Serial
   Visual attention operates through both
    automatic and effortful processes
       We automatically and rapidly identify stimuli that
        differ in only one single feature (e.g., size, color,
        orientation)
           Parallel processing


       Searching for two features (e.g., red and large)
        happens slowly and serially
Parallel processing allows us to process information from different visual features at the same time
by focusing on targets (here, the red objects) over distractors.
Auditory Attention Allows
Selective Listening
   We can attend to more than one message at
    a time but not well

   Selective listening
       We process some unattended information but in a
        weaker form than we process attended
        information
The participant receives a different auditory messages in each ear, but is required to repeat (“shadow”)
only one.
Selective Attention Can Operate
at Multiple Stages of Processing
   Change blindness

       We often miss large objects in our visual field
        when we are attending to something else

       Although most people do not believe they can fail
        to see large objects right in front of them,
        numerous studies show this is the case
Critical Thinking Skill
   Recognizing when “change blindness
    blindness” may be occurring

       Thinking we always notice large changes in our
        visual field may lead us to perceive things
        incorrectly
           Eyewitness


       Recognize the limits of attention
What Are the Basic Stages of
Memory?
 Sensory   Memory Is Brief

 Working   Memory Is Active

 Long-Term   Memory Is Relatively
 Permanent
Learning Objective

Describe the stages in the
 modal model of memory,
 including how long each
 stage lasts and how much
 information it can hold.
What Are the Basic Stages of
Memory?
   Three parts of memory:

       Sensory memory

       Short-term or working memory

       Long-term memory


   H.M.
(a) The information processing model compares the working of memory to the actions of a computer.
(b) The modal memory model serves as a useful framework for thinking about the basic stages of memory.
Sensory Memory Is Brief
   Visual and auditory memories are
    maintained at the sensory memory
    stage long enough to ensure a
    continuous sensory experience
Working Memory Is Active
   Immediate active memory is limited.
       Working memory holds information for about 20–
        30 seconds unless you make efforts to maintain
        information
       Memory span


   Chunking reduces information into
    meaningful units that are easier to remember.
Working Memory Is Active
   The components of working memory:
       Central executive
           The boss—filters information to long-term memory
           Retrieves from long-term memory as needed
       Phonological loop
           Encodes auditory information
       Visuospatial sketchpad
           Encodes visual information
       Episodic Buffer
           Holds temporary information about oneself
The working memory system details the components and processes of short-term memory.
Long-Term Memory Is
Relatively Permanent
   Long-term memory (LTM) is the potentially
    indefinite storage of all memories
   Distinct from working memory in duration and
    capacity
         Serial position effect
   Meaningful memories are stored in LTM in
    networklike structures
What Are the Different Long-
Term Memory Systems?
   Explicit Memory Involves Conscious
    Effort

   Implicit Memory Occurs without
    Deliberate Effort

   Prospective Memory Is Remembering
    to Do Something
Learning Objectives
Explain the differences among
 episodic, semantic, implicit,
 explicit, and prospective
 memories.

Provide an example of each of
 these types of memory.
What Are the Different Long-
Term Memory Systems?
   Memory is not a single process or brain
    system

   Fundamental differences exist among
    episodic and semantic memory, explicit and
    implicit memory, and prospective memory
Explicit Memory Involves
Conscious Effort
   Explicit, declarative memories that we
    consciously remember include:

       Episodic memory (personal events)

       Semantic memory (knowledge)
Implicit Memory Occurs
without Deliberate Effort
   Implicit memory consists of memories
    about which we have no conscious
    knowledge
       Procedural (motor) memories of how to do things
        automatically
   Implicit memory influences our lives in
    subtle ways
       Attitude formation
       Advertising
Prospective Memory Is
Remembering to Do Something
   Procedural memory consists of remembering
    to do something at some future time

   Has “costs” in terms of reducing attention and
    reducing working memory capacity
How Is Information Organized in
Long-Term Memory?
 Long-Term Storage Is Based on
  Meaning
 Schemas Provide an Organizational
  Framework
 Information Is Stored in Association
  Networks
 Retrieval Cues Provide Access to
  Long-Term Storage
Learning Objectives

Illustrate the organization of
   long-term memory.

Show how retrieval cues can
 determine what we remember.
Long-Term Storage Is Based
on Meaning
   Memory processes include encoding,
    storage, and retrieval

   Memories are stored by meaning
       Elaborative rehearsal involves encoding
        information in more meaningful ways and results
        in better memory than maintenance (repetition)
        rehearsal.
Participants are asked to consider a list of words according to how the words are printed, how they
sound, or what they mean.
Schemas Provide an
Organizational Framework
   Schemas are structures in long-term memory
    that help us perceive, organize, process and
    use information

   Cultural variations in schemas produce
    differences in what and how information is
    remembered
       Can lead to biased encoding
Information Is Stored in
Association Networks
   Networks of associations

       Formed by nodes of information

       Nodes are linked together

       Spreading activation
In this semantic network, similar concepts are connected through their associations.
Retrieval Cues Provide Access
to Long-Term Storage
   A retrieval cue is anything that helps access
    the right information stored in long-term
    memory
       Easier to recognize than recall information
       According to the encoding specificity principle,
        any stimulus encoded along with an experience
        can later trigger the memory of the experience
           Memory’s context also activated
What Brain Processes Are Involved
in Memory?

 There Has Been Intensive Effort to
  Identify Memory’s Physical Location
 The Medial Temporal Lobes Are
  Important for Consolidation of
  Declarative Memories
 The Frontal Lobes Are Involved in
  Many Aspects of Memory
 Neurochemistry Underlies Memory
Learning Objective

Describe the underlying changes
 in the brain when something is
 learned.
There Has Been Intensive Effort to
Identify Memory’s Physical Location

   Research during the past thirty years has
    demonstrated that memories are encoded in
    distributed networks of neurons in relatively
    specific brain regions

   Karl Lashley
       Unable to locate a specific site of memory storage
        (engram)
           Equipotentiality
There Has Been Intensive Effort to
Identify Memory’s Physical Location

   Memories are stored in multiple regions of
    the brain and linked through memory circuits
       Different regions responsible for storing different
        information


   Research has revealed that a number of
    specific brain regions contribute to learning
    and memory.
Medial Temporal Lobes: Important for
Consolidation of Declarative Memories

   Immediate memories become lasting
    memories through consolidation
   Consolidation involves changes in neural
    connections
   The hippocampus, a structure in the medial
    temporal lobe, is important for declarative
    memories
Four horizontally sliced brain images acquired using magnetic resonance imaging indicate that
regions of the sensory cortex are reactivated when we remember sensory-specific information.
Medial Temporal Lobes: Important for
Consolidation of Declarative Memories

   Spatial memory:
       Memory for the physical environment

       Place cells in the hippocampus aid spatial
        memory
           In lab, place cells fire only when a rat returns to a
            specific location, not in a new environment
           Taxi drivers
The Frontal Lobes Are Involved
in Many Aspects of Memory
   Extensive neural networks connect the frontal
    lobes with other memory regions of the brain

   Brain imaging studies show that the frontal
    lobes are crucial for encoding

   Activation of neurons in the frontal lobe is
    associated with deeper meaning
The amount of brain activation and the areas activated in the brain depend on the type and timing of
the material being remembered.
The Frontal Lobes Are Involved
in Many Aspects of Memory
   The frontal lobe may also play a role in
    working memory

       Patients with damage to frontal areas, human
        infants, and monkeys with frontal lesions all have
        difficulty with tasks associated with working
        memory
Neurochemistry Underlies
Memory
   A group of neurochemicals modulates the
    storage of memories (memory modulators)

   Epinephrine enhances memory
       Excreted from adrenal glands when an animal is
        excited or afraid
Neurochemistry Underlies
Memory
   The Amygdala:

       Probably responsible for memory modulation
        through activity in its norepinephrine receptors

       Amygdala is activated during emotional memory
           Gender differences
Studies have shown that men’s and women’s brains respond differently to emotional experiences and to
the memories of those experiences.
(Top) This image shows the greater activity in the right amygdala of a man’s brain while the man is
viewing emotionally arousing images. (Bottom) This image shows the greater activity in the left amygdala

of a woman’s brain while the woman is viewing emotionally arousing images.
When Do People Forget?

 Transience Is Caused by Interference
 Blocking Is Temporary

 Absentmindedness Results from
  Shallow Encoding
 Amnesia Is a Deficit in Long-Term
  Memory
Learning Objective

List and explain the basic
 processes used to understand
 forgetting.
When Do People Forget?
   Forgetting is the inability to retrieve memory
    from long-term storage

   The ability to forget is just as important as the
    ability to remember
       Forgetting allows us to function in normal society
Transience Is Caused by
Interference
   Forgetting over time occurs because of
    interference from both old and new
    information.
   Proactive interference
       Old information inhibits the ability to remember
        new information
   Retroactive interference
       New information inhibits the ability to remember
        old information
Proactive interference occurs when information already known (here, psychology material) interferes with the ability to
remember new information (here, anthropology material). Retroactive interference occurs when new information
(anthropology material) interferes with memory for old information (psychology material).
Blocking Is Temporary
   Blocking is the tip-of-the-tongue phenomenon
    when a person temporarily has trouble
    retrieving the right word, usually from
    interference from a similar word
Absentmindedness Results
from Shallow Encoding
   Inattentive or shallow processing causes
    memory failure

   Inattentiveness also leads to change
    blindness
       Cultural differences seem to exist in change
        blindness
Amnesia Is a Deficit in Long-
Term Memory
   Both injury and disease can result in amnesia

   The two basic types of amnesia are:
       Retrograde amnesia(the inability to recall past
       Anterograde amnesia (the inability to form new
        memories)
How Are Memories Distorted?
   Flashbulb Memories Can Be Wrong
   People Make Source Misattributions
   People Are Bad Eyewitnesses
   Critical Thinking Skill: Recognizing How the
    Fallibility of Human Memory Can Lead to Faulty
    Conclusions
   People Have False Memories
   Repressed Memories Are Controversial
   People Reconstruct Events to Be Consistent
   Neuroscience May Make It Possible to
    Distinguish between “True” and “False” Memories
Learning Objective

Describe how memories can be
 distorted.
Flashbulb Memories Can Be
Wrong
   The strong emotional response that attends a
    flashbulb memory may modulate the
    memory’s strength and affect the memory’s
    accuracy
People Make Source
Misattributions
   A person can misremember the source of a
    memory (source misattribution)
       False fame effect


   In cryptomnesia, a person thinks he or she
    has come up with a new idea, but has only
    retrieved a memory
People Are Bad Eyewitnesses
   Poor eyewitness recall occurs
     Particularly when people try to identify those
      of other ethnicities

   Suggestibility leads to misinformation
     Elizabeth Loftus and her colleagues



   Eyewitness confidence is high (whether they are
    right or wrong), which makes them convincing
Critical Thinking Skill
   Recognizing how the fallibility of human
    memory can lead to faulty conclusions
       Despite the fact that eyewitnesses are often
        wrong, people tend to believe them
       There is little or no relationship between a
        person’s confidence and the accuracy of the
        memory
       Remember that memory is often inaccurate and
        check it against facts whenever possible
People Have False Memories
   Source amnesia occurs when a person has a
    memory but cannot remember where he or
    she got the information

   Immature frontal lobes cause childhood
    amnesia
       Many events we remember from early childhood
        are constructed from information learned later in
        life
People Have False Memories
   False memories can be implanted

   Confabulation (the false recollection of
    episodic memory) can occur because of brain
    damage
       H.W.
Repressed Memories Are
Controversial
   One of the most heated debates in
    psychological science centers on repressed
    memories
   Some psychotherapists claim that long-
    repressed memories of traumatic events can
    resurface
   Evidence suggests that some therapeutic
    techniques can result in false repressed
    memories
People Reconstruct Events to
Be Consistent
   Memory bias:

       People’s memories change over time to maintain
        consistency between their past memories, their
        current knowledge, and their current attitudes
Distinguishing between “True” and
“False” Memories?
   When a memory is true (accurate), the brain
    regions activated by retrieval are the same
    ones that were active at encoding
   By examining brain activity at retrieval,
    researchers hope to distinguish true from
    false memories
   The current research has many flaws, but the
    techniques may be improved in the future
The fMRIs below come from a study in which the investigators examined brain activity while the subjects
engaged in deception. T-score is a statistical estimate of the size of the difference in neural activity between
truth and deception conditions; on the scale here, bright yellow indicates the strongest brain activity. As the
images show, various brain regions were involved in deceptive answers. The investigators were particularly
interested in their theory linking memory and language processes to deception, and activity in areas indicated
by arrows most strongly supported their theory.
How Can We Improve Learning
and Memory?

 Mnemonics     Are Useful Strategies
 for Learning
Learning Objective

Explain how we can use
 scientific knowledge about
 memory to improve memory.
Mnemonics Are Useful
Strategies for Learning
   Practice
       Memory is strengthened with repeated retrieval
           Frequent testing and active responding spaced out
            over time provides a strategy to enhance memory

   Elaborate the material
       When you relate new information to information
        you already know, you create more retrieval cues,
        which make you more likely to recall the new
        information later
Mnemonics Are Useful
Strategies for Learning
   Overlearn
       Creates stronger memory traces, probably
        because of repeated retrieval
   Get adequate sleep
       Because memories undergo consolidation during
        sleep, it is important to get adequate sleep
   Use verbal mnemonics
       Catchy verbal associations can act as retrieval
        cue
Mnemonics Are Useful
Strategies For Learning
   Use Visual Imagery
       Imagery requires you to pay attention
       Also uses both the verbal and visuospatial
        components in working memory, thus creating
        stronger memory traces
       External aids, including paper and pencil, can be
        helpful when you need to remember something
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