When we are actively working, we want information to be immediately available to us. In our brain, this happens in Working (short-term) Memory.
Long Term Memory is for extra information. It contains everything you know. It is storage for information that is not used right now but may be needed later.
Storage Capacity of Working and Long-term memory
Long-term memory capacity: huge
Working memory capacity: more modest
Memory span: way of measuring working memory capacity
Random, unrelated information: we can store about 7, plus or minus 2, items (5 – 9 items)’
Referred to as “the magic number 7”
Working Memory
“Loading platform” analogy
Long term memory must be “loaded” or “pass through” WM
How does it move? How is it transformed into Long term memory?
Rehearsed
Chunked
Chunking
Working memory can only handle a small number of items at one time. However what these packages contain can be up to us.
149162536496481
Can you remember all of these digits?
Chunking
If you look at these digits independently, you will fail to remember them!
What about if you organize them differently?
1 4 9 16 25 36 49 64 81
Now you only have to remember the relationship between these items. So working memory’s capacity is dependent on these chunks, not independent items.
Learner’s activities must be considered when examining memory
Maintenance rehearsal
Processing and organizing information: the “Royal Road into Memory”
Do you know whose picture is on 5 TL?
Athough people see 5 TL many many times, they seem to have little recollection of it’s layout
Depth of processing
Deep processing:
Meaning-based attention
Anything that connects new information to already-learned material
Material that “makes sense” will be encoded more efficiently
Results in superior recall
Depth of processing
Memory connections:
Links among ideas
Abstract similarities
When the time comes to recall something, these connections, established during initial learning or acquisition, can be used as retrieval paths.
Mnemonics
“Method of loci”
Based on rhythm/rhyme/melody/visualization
Research participants shown related elements, such as a doll sitting on a chair and waving flag (A), are more likely to associate the words doll, flag and chair than participants who are shown the three objects next to each other but not interacting (B).
A
B
Storage
Once encoded, must be stored until needed
Record (stored memory): memory trace or the engram
Storage process difficult to research: But: a memory is NOT stored in a single location: different aspects of a memory can be stored in different brain structures
Consolidation
Memory traces are not created instantly. A period of time is needed after the experience to become established in memory. This makes memories permanent. (You need to sleep in order for this to take place!!!!)
Evidence for consolidation?
Retrograde amnesia: a blow to the head can interrupt the process of consolidation for events that happened 1-2 hours before the accident occurred
Memory for events during that time period is lost
Retrieval
Storage is not enough; we must be able to access the memory when needed
With an adequate retrieval cue, sometimes we realize that encoding wasn’t the problem after all. Like, if you see the person’s face, you’ll remember their name. A word or a smell may help you remember. These are all cues (hints).
Retrieval cues
Context reinstatement
Re-creating or re-minding oneself of the context in which one originally learned something increases likelihood of being able to retrieve it later
Example: Studying for an exam in the same room you will take the test; returning to your hometown and remembering things you had “forgotten”
Inadequate encoding: Forgetting can often be traced to poor or missing strategies for encoding
Forgetting: we knew it once, but no longer
Passage of time
Can be graphed with a “forgetting curve” – the opposite of a “learning curve”
Ebbinghaus: Memory declines with time, more sharply at first, then more gradually
Memory failures
Decay: a process that occurs on a cellular level by normal metabolic “wear and tear” on cells involved with memory
Interference: New learning interferes – independent of the passage of time
Passage of time not a powerful factor in explaining forgetting
Number of intervening events a more useful variable to examine to explain forgetting
Other retrieval errors
Retrieval failure:
One type: the “tip of the tongue” phenomena
Who was the famous American basketball player who wore “23” as a uniform number?
Who was the man who played in the movie “Psycho”, with a knife in his hand in the shower scene?
Misinformation Effect
Imagine you eye witnessed a crime and see the thief flee in a blue car. The next day, you read a newspaper account of the same crime and learn that another witness reported that the thief fled in a green car.
How will this new information influence your memory?
The errors we make can be very large. People can be led to remember cars that were not actually present in an event, and whole buildings that do not exist. They can even recall events that never happened.
Misinformation Effect
It is common to ‘remember’ things that never happened.
Example of this is experiment by: Wade, Garry, Read, & Lindsay (2002)
People were shown photographs of themselves in a hot-air balloon and asked what they remembered. Most people remembered the experience. But the photos were made using photoshop. The people had never been in a hot-air balloon
Misinformation Effect
Misinformation can be used to insert new ideas into memory. In these cases the original memory may even be lost because the person who is given the misinformation (new information about an event that happened) overwrites the original memory with the fake one.
Difference between recollection memory and familiarity
Big problem for us: No reliable way to tell “good” memories (accurate) from “bad” memories (those that are false or contain misinformation or inaccuracy)
Techniques for improving memory
How to help us create better memories?
Techniques for improving “eyewitness identifications” that are more reliable:
Re-create mind-set
Minimize distractions/distractors
Unhelpful techniques:
Hypnosis
Amnesia : Memory Loss
Different brain tissue supports implicit memories as compared to explicit memories
Evident when studying anterograde amnesia
Lesions in hippocampus and temporal cortex: create anterograde amnesia
Lesions from other types of brain injury: create retrograde amnesia
Supports the theory that different brain structures/regions “handle” different types of memory
Retrograde amnesia
Forgetting the past, but being able to make new memories. Soldiers are sometimes unable to remember their experiences in battle-even the ones that occured a day before.
Anterograde Amnesia
Anterograde means ‘in a forward direction’. May be caused by a stroke or a physical trauma.
It is essentially an inability to learn anything new/make new memories.
Anterograde Amnesia
Famous case; Patient H.M.
He could read and write. His long-term storage is completely closed to new memories. His memories before the operation remain intact. He can function and comment intellectually on events.
Anterograde Amnesia
What is wrong with H.M.?
He had an uncle that he really loved. His uncle passes away and then he is told about the death of his uncle. He was deeply distressed when told about this, but the he forgot! Some time later he would ask where his uncle was, and was again told about his death. His sadness and grief was just as intense as before each time he hears this sad news. He said he is hearing it for the first time-with all the shock and grief.
Anterograde Amnesia
It turns out these anterograde amnesia patients can acquire some new memories. For example H.M. plays the piano and each time he plays a piece, he plays it more skillfully.
Distinction between different types of knowledge: memory for skill, memory for general knowledge, memory for episodes.
KNOWING HOW vs. KNOWING WHAT
Emotional Remembering
Does memory for emotional events differ in any systematic way?
Emotional events: remembered…
More vividly
More completely
More accurately
… than memories for emotion-neutral events
“Flashbulb memories”
Especially vivid memories
Focus: immediate and personal details
Special mechanism to produce this type of memory?
No evidence that these types of memories are in a special class with respect to immunity from error or extreme longevity
“Flashbulb memories”
They are likely to involve people we love and care about.
Some emotional memories are particularly long-lived, so that people claim to remember events from years and years ago “as if it were yesterday”.
Flashbulb memories are highly special events, usually unexpected and emotionally strong. Such as 9/11 terrorist attacks to the World Trade Center, or Princess Diana’s death.
Where and who were you with when you first heard these events? Most people remember all the details…
Memory and Trauma
Most traumatic events are well-remembered
Some events seem to be “enhanced” or even more vivid than other memories
Exceptions do exist and memory may be troubled/incomplete/absent:
Youth / age at time of event
Other confounding factors (sleep deprivation, head injury, medication/drug usage at time of event)