Memory

Three memory stores that differ in function, capacity and duration

  • Sensory memory

  • Working or short term memory

  • Long Term memory

Sensory Memory—divided into two types:

  • iconic memory/visual memory—brief memory of an image or icon

  • echoic memory/auditory memory—auditory sensory memories may last a bit longer than visual sensory memories

    • George Sperling studied iconic memory.

Sensory memory forms automatically, without attention or interpretation. Attention is needed to to transfer memory to working memory.

Short-Term Memory

  • Function—conscious processing of information

    • where information is actively worked on

  • Capacity—limited to 7+/- 2 items

  • Duration—brief storage about 30sec

Chunking

  • Grouping small bits of information into larger units of information

    —expands working memory load

    ex. 483 792 516

Long-Term Memory

  • Function—organizes and stores information

    • more passive form of storage than working memory

  • Unlimited capacity

Some Terms

  • Duration—thought by some to be more permanent

  • Encoding—process that controls movement from working to long-term memory store

  • Retrieval—process that controls flow of information from long-term to working memory store

LONG TERM MEMORY

  • Procedural Memory

  • motor skills, actions

  1. Implicit Memory(Nondeclarative Memory)

  • Memory without conscious recall

    • Cant be consciously recollected

Automatic vs. Effortful Encoding

  • Effortful Processing

    —requires attention and conscious effort

    —Examples:

    • memorizing your notes for your upcoming Intro to Psych exam

    • repeating a phone nu per in your head until you can write it down

Hierarchical Organization

  • Related items clustered together of form categories

  • Related categories clustered to form higher-order categories

  • Remember list item better if list presented in categories

    —poorer recall if presented randomly

  • Even if list items are random, people still organize info in some logical pattern

Why do we forget?

  • forgetting can occur at any memory stage

Tip of the tongue phenomenon

  • TOT—involves the sensation of knowing that specific info is stored in long-term memory but being unable to retrieve it

  • Can't retrieve info that you absolutely know is stored in your LTM

    • retrieving info is all or nothing

  • Retrieval—process of accessing stored info

  • sometimes info IS encoded into LTM

Measures of Retrieval

  • Recall—test of LTM that involves retrieving memories without cues, also termed free recall

  • Cued recall—test of LTM that involves remembering an item of info in response to a retrieval cue

  • Recognition—test of LTM that involvers identifying correct info from a series of possible choices

  • Serial position effect—tendency to remember items at the beginning and end of a list better than

Encoding Specificity

—when conditions of retrieval are similar to conditions of encoding, retrieval is more likely to be successful

—You are more likely to remember things if the conditions under which you recall them are similar to the conditions under which you learned them.

  • Context effects—environmental cues to recall

  • State dependent retrieval—physical, internal factors

The Forgetting Curve

  • Hermann Ebbinghaus first began to study forgetting using nonsense syllables

  • Nonsense syllables are three letter combinations that look like words but are meaningless(ROH, KUF)

4 Reasons for forgetting

  1. Encoding failure

    1. absentmindedness

    2. didn't pay attention enough to make it meaningful

  2. Decay theory

    1. memory traces fade away

  3. Interference Theory

    1. forgetting is caused by new memories interfering

    2. Retroactive and proactive

      1. new memories interfere with remember old memory

      2. old memory interferes with a new memory

  4. Motivated Forgetting

    1. Undesired memory is held back from awareness

      1. Suppression—conscious forgetting, think of other things

      2. Repression—unconscious forgetting(freudian)

Loftus Experiment

  • Subjects shown video of an accident between two cars

  • Some subjects asked: How fast were the cars going when they smashed into each other?

  • Others asked: How fast were the cars going when they hit each other?

Eye Witness Testimony

  • Scripts—type of schem

    —Mental organization of events in time

    —Example of a classroom script. Come into class, sit down, talk to friends, bell rings, instructor begins to speak, take notes, bell rings again, leave class etc.

  • Recall not an exact replica of original events

  • Recall a construction built and rebuilt from various sources

  • Often fit memories into existing beliefs or schemas

  • Schema—mental representation of an object, scene or event

Encoding Failure

  • leads to forgetting

Retroactive Interference

  • When NEW memory interferes with remembering old information

Proactive interference

  • When an OLD memory interferes with remembering NEW information

    • ex. where u parked your car last week interfering with remembering where u parked your car today

Biological basis of Memory

  • Karl Lashley searched for a localized memory trace or engram

    • Found that maze-learning in rats was distributed throughout the brain

  • Richard Thompson found that emory for simple classical conditioned responses was localized (in the cerebellum)

Aplysia—a sea snail was used to study how memories can change neurons

  • Amnesia—severe memory loss

  • Retrograde amnesia—inability to remember past episodic information; common after head injury; need for consolidation

  • Anterograde amnesia—inability to form new memories; related to hippocampus damage

Three memory stores: Sensory Memory, Working (Short-Term) Memory, Long-Term Memory.

Sensory Memory:

  • Types: Iconic (visual) and Echoic (auditory; may last longer);

  • Forms automatically without attention; attention needed to transfer to working memory.

Short-Term Memory:

  • Function: conscious processing of information; limited to 7±2 items; duration ~30 seconds.

  • Chunking: grouping small bits of information to expand memory load.

    • ex. 945 654 889

Long-Term Memory:

  • Function: organizes and stores information(passive); unlimited capacity; some consider duration permanent.

  • Key processes: Encoding (movement from working to long-term) and Retrieval (longterm back to working memory).

  • Types: Procedural (motor skills), Implicit (non-declarative; happens automatically).

Forgetting:

  • Can occur at any stage; includes Tip of the Tongue phenomenon.

  • Measures of Retrieval: Recall, Cued Recall, Recognition; Serial Position Effect(

  • The Forgetting Curve: Ebbinghaus’ early studies on forgetting.

    • Reasons: Encoding failure, decay, interference (retroactive and proactive), motivated forgetting (suppression and repression).

Loftus Experiment:

  • Showed how wording affects memory recall; relevant in eyewitness testimony.

  • Schemas: Mental organization of events (e.g., classroom scripts); recall is reconstructive, influenced by existing