The modal model because of the huge influence it has had on memory research.

Structure  Sensory  Short-term  Long-term Processes  Encoding: activities taking place during presentation of information (study phase)  Storage: activities taking place during the study-test interval  Retrieval: activities taking place when stored information is utilized (test phase) ▪ Failure to retrieve – forgetting

 Purpose  Passively registers input & briefly retains stimulus trace after stimulus vanishes  Functions  Helps us retain info that doesn’t last long  Aids perception by allowing you to continue processing after the stimulus is gone  Keeps accurate record of stimulation so most important can be processed further

 DURATION< 30 sec lifetime  CAPACITY~7 chunks unlimited  MAIN CODE acoustic- semantic articulatory  RETRIEVAL serialparallel  FORGETTING decay, interference displacement STMLTM

 Memory span  the number of items that can be correctly recalled in order (e.g., digit span test).  Miller (1956) “The Magical Number Seven, Plus or Minus Two” Limit of chunks in STM  Chunk: unit of info organized according to a rule or some familiar pattern  Chunk: collection of elements that are strongly associated.

B V S M T A U I vs. T V U S A I B M F B I J F K F D R L B J Task: immediate serial recall (“memory span”) Capacity of STM: "about seven chunks”

Demo

Support for A & S model  Two serial position effects  Primacy Effect  Better recall for words at beginning of list  Recalled from LTM  Recency Effect  Better recall for words at end of list  Recalled from STM

Support for A & S model  Effect on serial position curve  Speeding up presentation rate?  Eliminate primacy effect  Delaying the start of recall with an interfering task?  Eliminate recency effect

Task: free recall of word lists Primacy effect: better recall of first few words Recency effect: better recall of last few words Glanzer & Cunitz (1966): delay between study and test eliminates recency effect :

Which list is faster to read aloud? Which list is harder to recall? STM CAPACITY AND REHEARSAL TIME

Number of syllabesReading Rate 1mumps2.2 words/sec 2measles2.0“ 3leprosy1.7“ 4diphteria1.5“ 5tuberculosis1.3“ Task: immediate serial recall of 6-item lists The word length effect

% words in correct TYPE OF SERIAL position RECALL TASK: A S C STM: 5 words, one trial, no delay__%__%76% LTM: 10 words, four trials, delay__%__%72% Acoustically similar lists: mad, plan, nap, bag…. Semantically similar lists: big, large, huge, great… Control lists: pen, day, wish, bill…

 Varied set of digits held in STM  E.g., memory set size of four: 2, 5, 8, 1  Task: is it in the set? 2yes 7no Retrieval for STM: parallel or serial?

 Conclusions:  STM duration:  most info was gone after about 18 seconds.  Why do we forget?  Strong support for decay? Lachman, Lachman, & Butterfield (1979)

 Replicated the Peterson & Peterson Task.  But, they also analyzed their data by trial number.  1 st trial is 1 st word presented to participants  Conclusion:  Forgetting almost does not occur at the first trial,  But more forgetting with each succeeding trial.  Why? Adapted from Keppel & Underwood (1962)

Things learned prior to study can proactively interfere with memory STUDY phase. Things learned between study and test can retroactively interfere with memory TEST phase.

 Proactive Interference (PI) also occurs.  Proactive interference refers to forgetting that occurs due to prior learning.

 Clive Wearing: impaired STM but LTM deficit  Case of H. M. – Bilateral medial temporal lobectomy (amygdala, uncus, hippocampal gyrus and anterior 2/3 of hippocampus were removed) in 1953 to control for epileptic seizures. The resulting effect was profound anterograde amnesia – loss of LTM  Case of K. F. (Shallice & Warrington, 1970) – who suffered brain damage because of motorbike accident had normal LTM but poor STM. Evidence in digit span task performance (commonly used in ability tests).

Current status  Sensory memory is part of perception, rather than memory  Short-term memory is more flexible than just a passive storehouse  working memory  Parallel processing