Memory

What is memory?

“It isn’t so astonishing the number of things I can remember, as the number of things I can remember that aren’t so.” Mark Twain

“Memory…is the diary that we all carry about with us.” Oscar Wilde The Importance of Being Earnest

• The persistence of learning over time through the encoding, storage, and retrieval of information.

How does memory work?

External Events

Sensory Memory

Short-term

Memory

Long-term Memory

Sensory Input

Encoding

Encoding

Retrieval

Three Stages of Memory

• Encoding-Putting information in• Storage-where information is kept in the brain• Retrieval-getting information back out

Memory is like a computer…

Memory• Encoding

• Storage

• Retrieval

Computer• Installing software or creating files

• Hardware

• File Search

Information Processing

• Automatic- occurs without thinking

• Effortful- occurs when one purposely tries to think about something

Effortful Processing• Rehearsal- conscious repetition• Next-in-line effect- when you are next in line, your

memory is poorest for the information preceding you

• Spacing effect- studying over time produces the best memory results

• Serial position effect- in a list, one tends to remember the first and last items best

Encoding

Things that help us encode• Meaning- we need to know the context

• Imagery- mental pictures

• Mnemonic devices- memory aids

• Organization

Mnemonic Devices- Memory Aids

• Method of loci >Associate a memory with a place

• Keyword method >Associate a word with something that needs to be remembered

• Peg-word method >One is a bun, two is a shoe, three is a tree…

• Acronyms >ROY G. BIV

• Hierarchies >Split items into topics

• Chunking >Put into smaller units

8017686390 becomes (801) 768-6390

Storage

How does memory work?

External Events

Sensory Memory

Short-term

Memory

Long-term Memory

Sensory Input

Encoding

Encoding

Retrieval

How much can be remembered?

Sensory Memory

Short-term Memory

Long-term Memory

Almost nothing, unless it catches your attention

7 items, plus or minus 2

Almost everything, but only if you can get it out

How long?

Sensory Memory

Short-term Memory

Long-term Memory

Images- tenths of a second

Sounds- 3-4 seconds

As long as you are consciously thinking about it

Virtually forever

Neuroscience

Remember the brain cell?Nucleus

Cell Body

Dendrites

Terminal Branches

Myelin Sheath

Axon

So, what does that have to do with memories?• Experience neurons fire. • If they fire enough, new dendrites or terminal

branches form making the connection even stronger

Long-term Potentiation (LTP)• Increase in a neuron’s firing potential• More firing= stronger pathway= better memory

Types of Memories

Implicit (Procedural)• Memories stored

without conscious knowledge (i.e. classical conditioning)

Explicit (Declarative)• Memories stored with

conscious knowledge (i.e. what you remember from class)

Where are memories processed in the short term?

• Implicit – processed in the cerebellum

• Explicit- processed in the hippocampus

Where are memories stored in the long term?• Could be anywhere in the cerebral cortex or even

several places.

Retrieval

Types of Retrieval• Recall- information is recovered from the brain >Fill-in-the blank

• Recognition- identifying information when choices are given

>Multiple choice

• Relearning- how easily information can be stored again

>Studying for a comprehensive exam

What affects retrieval?• Priming- activating prior knowledge or

associations >picture of a rabbit primes the response “hare”

• Context effect >scuba divers remembered better in the context they learned the information

• Mood-congruent memory >if you are happy now, your memories seem happier

Forgetting

Seven Sins of Memory• Absent-mindedness- failure to encode• Transience- storage decay over time• Blocking- failure to retrieve

• Misattribution- confusing the source of information• Suggestibility- false memories can be created• Bias- belief-colored memories

• Persistence- unwanted memories

Interference- memories get in the way of each other

Proactive• Past memories get in

the way of new memories

Ex. You remember an old locker combination instead of the new one

Retroactive• New memories affect

the recall of old memories

Ex. You move to a new neighborhood. When you go back to the old one to visit your friends, you have forgotten some of the streets.

Memory Construction• Repression- the Freudian concept that painful

memories are kept out of consciousness

• Misinformation effect- putting misleading information into one’s memory of an event

• Source amnesia- attributing information to the wrong source