Psych CH.7 Memory: Constructing and Reconstructing Our Pasts

Memory

• Memory: The retention of information over
time.
• Paradox of memory: Our memories are remarkably good in some situations and
surprisingly poor in others.

The Reconstructive Nature of Memory

• When you recall an event are you experiencing it in first person or third
person?
• If you said third person, that demonstrates the reconstructive nature of
memory. You didn’t experience it that way, so the brain must have created it.
• Individuals from Asian countries are more likely than European Americans to
see themselves at a distance in such memories.

The Three Types of Memory

• Sensory Memory
• Short-Term Memory
• Long-Term Memory
• Vary along two dimensions:
• Span – how much information each system can hold
• Duration – over how long a period of time that type of memory can hold
information

The Assembly Line of Memory

Sensory memory——→ Short-Term memory——→ Long-Term memory

Sensory Memory

• Brief storage of perceptual information before it is passed to short-term
memory.
• Helpful because it buys our brains a bit of extra time to process incoming
sensations.
• Allows us to “fill in the blanks” in our perceptions and see the world as an
unbroken stream of events.

• Each sense uses its own form of sensory
memory.
• Iconic memory:
• The type of sensory memory that
applies to vision.
• Iconic memories last only about a
second, then they’re gone forever.

Echoic Memory

• Echoic or auditory memories can last as long as 5 to 10 seconds
• Eidetic memories for hearing – individuals can report their echoic memories for
an unusually long period of time.

Short-Term Memory

• A memory system that retains information for brief periods.
• Working memory: Your ability to hold on to information we’re currently thinking about, attending to, or processing actively.
• Working Memory Task

Memory Loss from Short-Term Memory

• Decay: Fading information from memory over time.
• Interference: Loss of information from memory because of competition from additional
incoming information.

• Retroactive interference: Occurs when learning something new hampers earlier learning.
• The new interferes with the old
• Proactive interference: Occurs when earlier learning gets in the way of new learning.
• The old interferences with the new.

The Capacity of Short-term Memory: The Magic Number
• The digit span of most adults is between 5 and 9 digits with an average of 7
digits.
• 7 plus or minus 2 is the magic number
• Universal limit of short-term memory
• Applies to:
• Numbers
• Letters
• People
• Vegetables
• Cities
• Phone numbers in North America are exactly 7 minutes long.

Levels of Processing

• Depth of transforming information, which influences how easily we remember it.
• Pearson Video – Depth of Processing

• Three levels of processing of verbal information:
• Visual: Most shallow
• Phonological (sound-related): Somewhat less shallow
• Semantic (meaning-related): Deepest

Depth Of Processing

• The idea is not falsifiable.
• It’s impossible to determine how deeply we’ve processed a memory in the first place
• “Depth” is basically how well participants remember at a later time.

Long-Term Memory

• Relatively enduring store of information
• Includes facts, experiences, and skills we’ve acquired over our lifetimes.

• Long-term memory is large.
• We don’t know its limits
• Some estimate up to 500 huge online
encyclopedias – each about 1,500 pages long
• Long-term memory often endures for years,
even decades, and sometimes permanently.

Long-Term Vs. Short-Term Memory

• Primacy effect: The tendency to remember stimuli, like words, early in a list.
• Recency effect: The tendency to remember stimuli later in the list.
• We also tend to remember things that don’t seem to match or seem odd.

• Serial position curve:
• Graph depicting both primacy and recency effects on people’s ability to recall items on a list.

Types of Long-Term Memory

• Semantic memory:
• Our knowledge of facts about the world
• Episodic memory:
• Recollection of events in our lives
• Use different parts of the brain, but common neural networks may bring together
semantic and episodic memories regardless of their content.

• In what year did the United States become independent from Great Britain?
• Semantic memory
• What Republican candidate for president did Barack Obama defeat in the 2012
U.S. election
• Semantic memory
• How old were you when you first tried to ride a bicycle?
• Episodic memory
• Where did you celebrate your last birthday?
• Episodic memory

• Explicit Memory:
• Memories we recall intentionally and of which we have conscious awareness
• Semantic and episodic memory are examples of explicit memory
• Sometimes also called declarative memory
• Implicit Memory:
• Memories we don’t deliberately remember or reflect on consciously.
• Ex: Going through the steps of unlocking our front doors

Three Processes of Memory

Encoding

Storage

Retrieval

Encoding: Getting Information Into Our Memory Banks

• Many of our memory failures are failures of encoding
• Once we lose the chance to encode an event, we’ll never remember it

Retrieval

• Retrieval:
• Reactivation or reconstruction of experiences from our memory stores
• Many types of forgetting result from failures of retrieval:
• Our memories are still present, but we can’t access them.

Measuring Memory

• Recall:
• Generating previously remembered information
• Ex: Essay questions – generating previously remembered information on our own
• Recognition
• Selecting previously remembered information from an array of options
• Ex: Multiple-choice questions – selecting previously remembered information from an array of options

Encoding Specificity

• Phenomenon of remembering something better when the conditions under which
we retrieve information are similar to the conditions under which we encoded it
• I might have mentioned to you before about mints
• Sitting in the same seat you did during the lecture and when you take the test

Context-Dependent Learning

• Superior retrieval of memories when the external context of the original memories
matches the retrieval context
• Students tend to do slightly better on their exams when tested in the same
classroom in which they learned the material
• Sorry guys!
• But not super powerful and not always replicated

State-Dependent Learning

• Superior retrieval of memories when the organism is in the same physiological or
psychological state as it was during encoding.
• People who learn something while drunk remember those things better when
they are drunk than when they are sober

Mood Dependent Learning

• Similar to state-dependent learning but with mood.
• Find it easier to recall and recognize unpleasant memories than pleasant ones
when they’re sad and vice versa
• Might explain some things about depression!
• BUT – retrospective bias
• Our current psychological state can distort memories of our past

Amnesia

• Retrograde amnesia
• Loss of memories from our past
• Think “retro” and old
• Anterograde amnesia
• Inability to encode new memories from our experiences

• Generalized amnesia
• Those who have lost all details of their previous life
• Extremely rare
• Retrograde amnesia isn’t that common either
• Anterograde amnesia is more common among those with brain damage
• Recovery from amnesia is often portrayed as “abrupt” but it is normally gradual if at all.

Emotional Memory

• The amygdala is responsible for the emotional components of memories – especially fear
• The amygdala interacts with the hippocampus during the formation of memory

• Amygdala-damaged individuals remembered facts about the fear-producing
experience but did not experience the fear itself
• Hippocampal damaged person experienced the fear, but not facts surrounding
the fear-producing memory
• The amygdala helps us recall the emotions associated with fear-provoking
events and the hippocampus helps us recall the events themselves.

Erasing Painful Memories

• Emotional memories can persist, even if they often become distorted over time
• Hormones adrenaline and norepinephrine are released in the face of stress and
stimulate protein receptors on the nerve cells, which solidify emotional memories.

The Biology of Memory Deterioration

• As we age, cortical tissue decreases
• Some theorize that cognitive impairments (memory) doesn’t occur until a “critical”
amount of tissue has been lost

Infants Implicit Memory

• Infants demonstrate an ability to retain memory
• The amount of time that can pass where they can still remember increases as
they age
• If anything about the environment in which they were conditioned changed, they
couldn’t remember (state-dependent learning?)

Infantile Amnesia

• Inability of adults to remember personal experiences that took place before an
early age
• Earliest memories around 2-3 years (two is VERY early)
• Regardless these memories aren’t as trustworthy and reliable
• Earliest memory content varies by culture

• Why?
• Hippocampus isn’t fully developed
• We might not possess the brain architecture needed to retain memories of events
• We possess little or no concept of self – can’t encode or store memories of their experiences in a meaningful fashion
• I argue language.

False Memories

• Hypnosis (This is why I don’t like it).
• Nadean (130 personalities)
• Memories surfaced after she participated in repeated sessions involving guided imagery (the therapist asks clients to imagine past events)
• Hypnotic age regression – the therapist uses hypnosis to “return” clients to the psychological state of childhood
• Nadean was subjected to an exorcism and a 15-hour marathon therapy sessions
• Dissociated Identity Disorder (DID) Multiple Personality Disorder
• Characterized by the existence of “alter” personalities or “alters”

Flashbulb Memories

• Emotional memory that is extraordinarily vivid and detailed
• Don’t decay over time like ordinary memories
• Phantom flashbulb memory:
• Capture the idea that many seeming flashbulb memories are false
• After 32 months, 40% of the memory reports contained “major distortions” relative to their initial recollection only 3 days after the event.
• Typically contain substantial kernels of accuracy.

Misinformation Effects

• Misinformation effect:
• Creation of fictitious memories by providing misleading information about an
event after it takes place
• Participants were shown brief clips of traffic accidents and asked the participants
to estimate the speed of the vehicles involved.
• Varied wording:
• “About how fast were the cars going when they ____ each other?”
• Contacted, hit, bumped, collided, and smashed
• Inserted word affected the speeds they estimated

Eyewitness Testimony

• 375 prisoners, including 21 who served time on death row, have been acquitted
of a crime and released because their DNA didn’t match genetic material left by
perpetrators
• 63% of these cases involved eyewitness identification

• Eyewitness misidentification is the most common cause of wrongful convictions
• When witnesses seem sure they’ve identified a culprit, juries tend to believe them
• The correlation between witnesses’ confidence and the accuracy of their testimony is often modest

• Rarely are you going to get a perfect image in your mind of an assailant during a
crime.
• Eyewitness testimony is less likely to be accurate when people observe
individuals of races different from their own
• When they talk to other witnesses
• When they catch only a brief glimpse of the criminal
• Or when they view a crime under highly stressful circumstances
• Some mistake the perpetrator’s appearance for someone they’ve seen shortly
before the crime

• Weapon focus:
• When the crime involves a weapon, people understandably tend to focus on the weapon rather than the perpetrator’s appearance

Learning Tips

• Distributed versus massed study:
• Spread out your study time – review your notes and textbook in increments
rather than cramming
• Testing effect:
• Put down what you’ve read, and test yourself frequently on material (sorry guys, I do that a lot in class!)
• Elaborative rehearsal:
• Connect new knowledge with existing knowledge rather than simply memorizing facts or names

•Levels of processing:
• Work to process ideas deeply and meaningfully –avoid taking notes word for word from instructors’ lectures or slides. (This is why I give the PowerPoint to you in advance!) Try capturing the information in your own words and using other concepts from the course
• Mnemonic devices:
• The more reminders or cues you can connect from your knowledge base to new material, the more likely you are to recall new material – including the material you learned in this chapter!