Definition of Memory

The process by which we acquire, store, and retrieve information

Functions of Memory

To provide our consciousness with continuity

To allow us to adapt to situations by calling on past skills and experiences

To enrich our emotional life by allowing us to remember past moments

Stages of Memory (Atkinson & Shifrin) Encoding Storage Retrieval

Levels of Processing during Encoding1. Effortful—requires concentration2. Automatic

Space Time Frequency Well-learned material

Types of memory (Atkinson and Shrifrin) Sensory memory Short-term memory Long-term memory

Sensory memory Stores sensory events in their original form

briefly Iconic memory—visual memory (traces) Echoic memory—auditory memory Flashbulb memory—episode of very detailed

recall; Souvenirs—a sensory reminder of something

that happens (smell, taste, sound, etc.) Selective attention; cocktail party phenomenon

Short-term memory Transferred to conscious awareness from

sensory memory Something must be processed in working

memory before it moves to long-term memory Working memory—very limited capacity memory

storage that lasts only 30 seconds or so Can hold 5-9 pieces of information Can make this larger by chunking Working memory is basically the newer term for short-

term memory

Long-term memory

Very large capacity; some say limitless Can store things permanently (more or

less) Rehearsal gets things into LTM

Maintenance rehearsal—simple repetition Elaborative rehearsal—create associations

Types of Long-term memory

Nondeclarative or procedural—how to do things

Declarative—facts and personal events Semantic memory—knowledge of facts Episodic memory—memory of personal

experiences

Ways to improve memory

Mnemonics: memory aids, especially those that use visual imagery or organizational devices

Make up a jargon or song about what you’re trying to remember

Create a visual image of things like grocery lists.

Come up with acronyms—ROY G BIV for colors of the rainbow.

Semantic network

A hypothetical organized network of related facts and knowledge in memory

It’s thought that we store items together with associations between them, and these interconnected pieces of information make up the semantic network.

It’s believed we also have “episodic networks” for memories of our own lives.

Spreading activation

The process by which recalling one bit of information along the semantic network triggers memory of another idea.

Example: Thinking of everything you know about the 1980s; one memory or thought will trigger another

Role of emotion in memory

Stress hormones cue brain that something needs to be remembered.

Amygdala boosts activity in hippocampus, where new memories are created.

Stronger emotional events stronger memories (as in flashbulb memories).

The hippocampus

Part of the limbic system (along with the amygdala) that is responsible for forming new memories.

Active during stage 3 & 4 (slow-wave) sleep; the greater the hippocampus activity during sleep after a training experience, the better the next day’s memory.

Where are memories stored?

Not in the hippocampus; it acts more as a “loading deck” for new memories before they’re shipped to the cortex.

Parts of the frontal and temporal lobes are involved in memories, but there is no one specific “memory storage” location.

Some memories are held in the left hemisphere; others in the right.

The cerebellum’s role in memory storage Seems to hold implicit (procedural)

memories Also seems to hold the implicit

memories formed from classically conditioned responses

Ebbinghaus’s research

Did experiments on memorizing lists of nonsense syllables to see how long it took him to forget them

Huge drop in retention in first few hours More than 60% is lost after 9 hours

Ebbinghaus’s conclusions Amount remembered depends on the time

spent learning. Additional rehearsal increases retention.

Learn and remember better when it’s spaced over time (spacing effect)

Cramming (“massed practice”) is not as effective as “distributed study time.” Cramming may produce speedy short-term memory, but it won’t stay in memory long-term.

Three ways to test memory

Recall—reproduction with no cues (essay tests)

Recognition—reproduction with cues (multiple choice)

Relearning—memorizing a second tiem with less effort

Why do we forget?

Code things ineffectively Interference (proactive, retroactive) Motivated forgetting (repression) Amnesia

Anterograde (amnesia for events AFTER an injury Retrograde (amnesia for events BEFORE an

injury Posttraumatic (alternating lucidity & confusion

Primacy & recency effects

Together, these make up a concept called the serial position effect.

Primacy effect—you remember items at the beginning of the list better

Recency effect—remember things at the end of the list (probably reflects STM storage)

Moods & Emotions in Retrieval State-dependent memory—improved recall

when in the same emotional state as you were in when the info was stored

Mood-congruence effects—memory is better for information consistent with your mood

Proactive vs. retroactive interference Proactive—something you learned

previously interferes with something new

Retroactive—something you learned recently interferes with something old.

Infantile Amnesia Autobiographical memory--Memory of our own lives Infantile amnesia—the inability to remember events

before the age of 2-3 Could be because hippocampus doesn’t develop

until later (cerebellum, an “older” part of the brain, handles procedural memory & conditioned responses)

May not have enough language skills before age 2-3

Do not have a well-developed sense of self

Eidetic memory

“Photographic” memory—no such thing exists. There is something called eidetic memory that involves a very high degree of recall. Common in childhood but not in adulthood. Falls off as language skills increase. Common in autistic children.

False memories

Have less specific detail than real memories; they’re confined to the “gist” of the situation

Once formed, can be very persistent and outlast real memories.