MEMORY
Memory
Any sign that
Information Processing
•
Encoding – (Getting information into the brain)
•
Storage – (Retaining the encoded information)
MEMORY – Page 257 (Excellent
Diagram)
•Sensory Memory - The immediate, very brief recording of sensory information in the memory system.
•Short Term Memory (AKA Working Memory) - Activated memory that holds a few items briefly, such as the seven digits of a phone number while dialing, before the information is stored or forgotten.
Sensory Memory Experiment
K ZR
Q B T
Sensory Memory – Lightening Fast
•Iconic Memory – (a fleeting photographic memory) a momentary sensory memory of visual stimuli; a photographic or picture-image memory lasting no more than a few tenths of a second.
Working/Short Term Memory
•Among the vast amounts of information registered by our sensory imagery memory, we illuminate some with out attentional flashlight.
•Unless our working memory (STM) meaningfully encodes or rehearses that information, it quickly disappears from our short term store.
•Short-term memory is limited not only in duration (3-7 seconds.) but also in capacity, typically storing about seven bits of information, plus or
ENCODING
ENCODING: Getting the Information In
•How we encode ….
•Automatic Processing – without conscious effort you automatically process information such as space, time, frequency, well-learned
information (such as word meanings).
•Effortful Processing – encoding that requires attention and conscious
Hermann
Ebbinghaus
(1850-1909)
Effortful Processing
•
Rehearsal
– the conscious repetition of
Rehearsal – Ebbinghaus Experiment
•JIH, BAZ, FUB, YOX, SUJ, XIR, DAX, LEQ, VUM, PID, KEL, WAV, TUV, ZOF, GEK, HIW
•After the first day of learning, Ebbinghaus could remember very few words …however, the were not entirely forgotten …
•The more frequently he repeated the words aloud on day 1, the fewer repetitions he needed on day two.
•Simple Principles:
•1. The amount remembered depends on the time spent learning.
Rehearsal Continued
•Massed practice (cramming) can produce speedy short-term learning, but
distributed practice/study time produces better long-term results.
•Spacing Effect – The tendency for distributed study or practice to yield better long-term retention than is achieved through massed study or
practice.
•The Testing Effects - testing repeatedly improves learning
Which names will you most likely
remember????
HELLO,
I’D LIKE TO
Rehearsal Continued
•Serial Position Effect – Our tendency to recall best the last and first items in a list.
•When you meet a group of people, you will most likely remember the first few names and possible the last name.
•Last name is remembered due to the recency effect
•If you were asked the following day … you would probably best remember only the first few names.
Levels of Encoding Experiment …
1. Is the word in capital letters?
2. Does the word rhyme with train?
3. Would the word fit in this
sentence? The girl put the ______ on the table?
WHICH WORD WILL YOU MUST LIKELY REMEMBER??? WHY?
•CHAIR
•Brain
•Gun
What We Encode
Visual Encoding – the encoding of picture images
Acoustic Encoding – the encoding of sound, especially the sound of words
Semantic Encoding – the encoding of meaning, including words
***The deeper semantic processing produces better recognition later than does shallow processing such as appearance (visual encoding) and sound (acoustic encoding).
Ebbinghaus estimated that compared with learning nonsense material, learning
meaningful material required one-tenth the effort.
*** The amount remembered depends on both the time spent learning and on you making it meaningful.
Helpful Encoding Techniques
•Rehearsal
•Imagery – mental pictures (especially when combined with semantic encoding)
•MNEMONIC – memory aids, especially those that use imagery and organizational devices.
•Relating new material to your own experience and things you already know.
•Organizing Information into helpful Hierarchies (i.e. Outline format)
Encoding Cont. … Chunking
•Chunking – organizing items into familiar, manageable units such as letters, words, and phrases, we recall it more easily. This often occurs automatically.
Hierarchy Example
Encoding
(Automatic and Effortful)
Meaning Imagery Organization
Retaining Information
WORLD MEMORY
CHAMPIONSHIP
RECORDS – PAGE 268
LTM Champion
During the winter
and early spring
the Clark’s
Nutcracker can
locate up to
6000
caches
of pine
seeds it had
LTM - Karl
Lashley (1950)
Helped determine that memories do not reside in single, specific spots in the brain.
Trained rats to find their way out of mazes
Then, he cut pieces of their cortexes and retested their memories.
No matter which small brain sections were
LTM – Synaptic
Changes
Synapse:
meeting place where
neurons
Aplysia
Neuroscientist Eric Kandel studied this type of sea slug for 45 years
His study has increased our understanding of the neural basis of learning.
LTP
Aplysia
While learning occurs,
the slug releases more
of the neurotransmitter
serotonin
.
These synapses then
become more efficient
at transmitting signals.
Increased synaptic
Long-term
Potentiation (LTP)
(The potential for firing has been strengthened)
An increased in a synapse’s firing potential after brief, rapid stimulation.
Believed to be the neural basis of learning.
The sending neuron now needs less prompting to release NTs The receiving neuron’s
receptor sites may increase (Overall …. Better
Interesting Facts About LTP
•Drugs that block LTP interfere with learning
•Mutant rats engineered to lack an enzyme for LTP can’t learn their way out of a maze ☹
•Rats given a drug that enhances LTP will learn a maze with half the usual number of mistakes.
•Injecting rats with a chemical that blocks the preservation of LTP erases recent learning.
•This knowledge could help to find a cure for Alzheimer’s and help produce other memory enhancing drugs.
•CREB (protein)
•Glutamate (neurotransmitter)
Memory and Emotion
•
Stronger emotional experiences make for stronger
more reliable memories.
•
People given drugs to weaken emotions have
more trouble remembering.
Flashbulb
Memories
A clear memory of an emotionally significant moment or event.
Your first kiss
Where you were on 9/11 Shocking Events
Misinformation can seep into the memories.
Amnesia
•
Loss of Memory
•
Retrograde Amnesia
– can’t remember some, or
all, of the past
H.M.
“The most important patient in the history of brain science.”
In 1953, surgically removed a brain area necessary for laying new conscious memories and facts.
Old memories remained intact However – he could no longer form new explicit memories.
“I’ve known H.M. since 1962, and he still doesn’t know who I am.” – his long term
Jimmie
•Psychologist Oliver Sacks worked with “Jimmie”
•Jimmie damaged his brain in 1945 --- he then could not remember anything (thus, no time elapsed) after his injury.
•Asked in 1975 to name the U.S. President: Jimmie replied, “FDR’s dead. Truman’s at the helm.”
•Jimmie would give his age as 19
•Episode with Sacks and mirror
Odd Findings
People like H.M. and Jimmie can still learn certain tasks
• Where’s Waldo experiment
• Find their way to the
bathroom – without being told where it is.
• Can be classically conditioned!
Implicit
Memory
•
Retention independent of conscious
recollection. (Also called
nondeclarative or procedural memory)
•
Learn “How To” Do Something
•
I.e. motor skills such as bike riding
and playing an instrument
•
Classical conditioning – reflexive
learning
•
Although one cannot form new explicit
memories they can still form new
Explicit
Memories
Memory of facts
and experiences
that one can
consciously
know and declare
(also called
Long Term Memory
Cerebellum - Implicit
Hippocampus
• Brain scans and autopsies of people with amnesia reveal that new
explicit memories of names, images, and events are laid down in the hippocampus.
• Left Hippocampus damage – trouble remembering verbal info
• Right Hippocampus damage – trouble remembering visual details
Hippocampus
•Is active during slow-wave sleep, as memories are processed and filed for later retrieval.
•The greater the hippocampus activity during sleep = the better the next day’s memory.
•During sleep, our hippocampus and brain cortex display simultaneous activity rhythms, as if they were having dialogue.
Hippocampus
•
Acts as a loading dock – memories are not permanently stored in
the hippocampus.
•
Removing the hippocampus 3 hrs after rats learn a maze disrupts
long-term memory formation
•
Removal 48 hours later does not
Cerebellum – (Processes Implicit Memories)
•Skills
•Motor Control
•Classical Conditioning
Getting Information Out
ANYTHING STORED IN
LTM LIES DORMANT,
WAITING TO BE
Retrieval
•To remember an event requires more than getting it in (encoding) and retaining it (storage). On must also be able to retrieve it.
•Recall – a measure of memory in which a person must retrieve information learned earlier; fill-in-the blank test.
•Recognition – a measure of memory in which the person need only identify items previously learned; multiple choice test
•Relearning – a measure of memory that assesses the amount of time saved when learning new material.
Retrieval Cues
Anchor points you use to help you access
information.
The more retrieval cues you have, the better chances for finding the memory.
Best cues come from associations we form at the time we encode a memory. Tastes, smells, sights often evoke
Priming
Often our associations are activated, or primed,
without our awareness
Priming is often
“memoryless memory” – although you don’t
Rapid Fire
•How do you say this word?
•S-H-O-P
•What do you do when you come to a green light?
Context Also Influences Retrieval
•Putting yourself in the same context where you experienced something can prime your memory.
•Scuba divers experiment – (words heard underwater are best recalled underwater / words heard on land are best recalled on land)
Mood Also Affects Retrieval
•Events in the past may have aroused a specific emotion that later primes us to recall its associated events. When you return to that state, you will recall what was encoded in that state.
•State-dependent memory
Mood-congruent
Memory
The tendency to recall
experiences that are consistent with one’s current good or bad mood.
When happy, you recall happy events and therefore see the world as a happy place, which helps prolong our goods mood.
Why do we forget?
Jill Price
Remembers
everything since
age 14, including
both the joys and
the unforgotten
hurts.
Encoding
Failure
We cannot remember what we have not encoded.
Oftentimes, without effort or the right kind of effort many memories will never form.
Storage Decay
Even when we encode something well, we can still forget it.
Ebbinghaus’
experiments reveal that forgetting is initially rapid, then levels off.
Fading of physical
Retrieval Failure -Interference
•Often, forgetting is not memories discarded, but memories unretrieved. Sometimes Due To:
Interference – learning of some items may interfere with retrieving others, especially when they are similar.
Proactive interference –something you learned earlier disrupts your recall of something you experienced later. (hinders recall of newer info)
Retroactive interference – something you have newly learned or are presently learning disrupts your recall of something you had learned earlier. (hinders recall of older information)
Retrieval Failure - Motivated Forgetting
•People unknowingly revise their own histories. Memory can be unreliable and self serving.
•Repression – unconsciously banish anxiety-arousing memories
•People’s efforts to intentionally forget neutral material are often
Forgetting
Summary
Depending on
MEMORY
CONSTRUCTION
We often construct our memories as we
encode them, and we may also alter our
memories as we withdraw them from
storage.
We don’t just
retrieve
memories – we
Elizabeth Loftus
Has studied memory construction.
“How fast were the cars going when the smashed into each other?”
Misinformation Effect
After exposure to subtle misinformation, many people misremember.
• This can be detrimental to eye-witness testimony
• Also may effect child eyewitness recall
“The human mind comes built-in with PhotoShopping software.”
You can literally create false memories that you do not realize are false. Experiments:
Digitally altered childhood photos of balloon ride
Memory and Imagination
• Often become fused
• Imagination inflation occurs partly because visualizing something and actually perceiving it activates similar brain areas.
Source Amnesia
•We retain the memory of the event, but not the context in which we acquired it.
•“Where do I remember you from?”
•“Was that a dream or did it really happen”
Memory Construction
•Explains why 79% of 200 convicts are later exonerated by later DNA testing.
•It explains why “hypnotically refreshed” memories of crimes can be unreliable
•Story about Psychologist Donald Thompson being falsely accused of rape – he was seen on television right before incident occurred.
Memory Construction
•Also can be detrimental to Child Eyewitness accounts of abuse.
•58% of preschoolers produced false (often vivid) stories regarding one or more events they never experienced.
•Study – asked 3-year olds to show on a anatomically correct doll where a pediatrician had touched them. 55% of children who had not received genital examinations pointed to either a genital or anal area on the doll.
Repressed or Constructed
Memories of Abuse?
•In one American survey, the average therapist estimates that 11% of the population – some 34 million people – have repressed memories of
childhood sexual abuse.
•Considering what we have just discussed, what are some implications of this statistic?
•Studies show that the most common response to trauma is not
banishment of the memory but rather vivid haunting memories of the event.
Improving Memory
• Study Repeatedly
• Make the material meaningful
• Activate Retrieval Cues
• Use mnemonic devices
• Minimize Interference
• Sleep More
• Test you own
