Encoding, storage and retrieval, the stage model, working memory, levels of processing, kinds of long-term memory, why we forget and how to remember better.
Key ideas
Memory works in three stages: encoding (registering), storage (keeping) and retrieval (bringing back).
In the stage model, attention moves information from sensory memory to short-term memory, and elaborative rehearsal moves it to long-term memory.
Chunking groups small units into meaningful chunks, so short-term memory holds more.
Working memory (Baddeley) has a phonological loop, a visuospatial sketchpad and a central executive.
Processing for meaning (semantic) gives better retention than processing shape or sound (Craik and Lockhart).
We forget through trace decay, interference and retrieval failure; Ebbinghaus found forgetting is fast at first and then levels off.
Mnemonics using images (keyword, method of loci) and organisation (chunking, first letters) help, but deep processing and good cues matter most.
Remember
Sensory memory
large capacity, less than a second (iconic = visual, echoic = sound)
Short-term memory
about 7 ± 2 items, under 30 seconds without rehearsal
Long-term memory
unlimited capacity, up to a lifetime
Chunks
number of items ÷ chunk size, e.g. 36 digits in 4s = 9 chunks
Long-term memory types
declarative (episodic: life events; semantic: facts) and procedural (skills)
PQRST
Preview, Question, Read, Self-recitation, Test
Watch out
Confusing the interferences: proactive is old learning blocking new, retroactive is new learning blocking old.
Calling riding a bicycle semantic memory; skills are procedural.
Thinking repetition alone (maintenance rehearsal) moves information to long-term memory; linking it to what you know does.
Worked example
Suppose a 36-digit number is grouped into chunks of 4. How many chunks are there, and can short-term memory (7 ± 2, so at most about 9 items) hold them all?