Cognitive Processes PSY 334 Chapter 6 – Human Memory: Encoding and Storage

Ebbinghaus  First rigorous investigation of human memory –  Taught himself nonsense syllables DAX, BUP, LOC  Savings – the amount of time needed to relearn a list after it has already been learned and forgotten.  Forgetting function – most forgetting takes place right away.

Memory Models  Atkinson & Shiffrin – proposed a three- stage model including: Sensory store – if attended goes to STM Short-term memory (STM) – if rehearsed goes to LTM Long-term memory (LTM)  No longer the current view of memory. Still presented in some books.

Criticisms of STM  Rate of forgetting seemed to be quicker than Ebbinghaus’s data, but is not really.  Amount of rehearsal appeared to be related to transfer to long-term memory. Later it was found that the kind of rehearsal matters, not the amount. Passive rehearsal does little to achieve long-term memory.  Information may go directly to LTM.

Depth of Processing  Craik & Lockhart – proposed that it is not how long material is rehearsed but the depth of processing that matters.  Levels of processing demo.

Working Memory  Baddeley – in working memory speed of rehearsal determines memory span. Articulatory loop – stores whatever can be processed in a given amount of time. Word length effect: 4.5 one-syllable words remembered compared to 2.6 long ones. 1.5 to 2 seconds material can be kept. Visuopatial sketchpad – rehearses images. Central executive – controls other systems.

Delayed Matching Task  Delayed Matching to Sample – monkey must recall where food was placed. Monkeys with lesion to frontal cortex cannot remember food location. Human infants can’t do it until 1 year old.  Regions of frontal cortex fire only during the delay – keeping location in mind. Different prefrontal regions are used to remember different kinds of information.