LTM and STM

• MSM: describes how information flows through the memory system

  
• sensory register: all stimuli from the environment pass into this (someone talking).

  • coding = modality-specific (depends on the sense), iconic = visual and echoic = acoustically
  • duration = less than a second
  • capacity - high

  attention = info passes further into the memory system if you pay attention to it
• STM: a temporary store because it has a limited-capacity before it starts to forget things

  • coding = mainly acoustically
  • duration = 18 seconds unless it is rehearsed
  • capacity = 7+/-2

  maintenance rehearsal: occurs when we repeat material to ourselves over and over again - keep in STM as long as we rehearse it long enough for it to pass into LTM
• LTM: potentially permanent store for information, rehearsed a prolonged time

  • coding = semantically
  • duration = potentially unlimited
  • capacity = lifetime

  when we want to recall something from LTM, it has to go back through STM - process called retrieval
• MSM:

  strength:

  • baddeley support: tend to mix up words that sound similar when we use our STM, and mix up words that have similar meanings - shows STM and LTM are separate memory stores

  weakness:

  • everyday life we tend to remember important things rather than random digits - MSM not a valid model of how memory works in our everyday lives as we have to remember more meaningful information
• LTM: Tulving (1985) - 3 types of LTM: episodic, semantic and procedural

  • episodic = ability to recall events, time-stamped, conscious effort to recall
  • semantic = shared knowledge of the world, not time-stamped,
  • procedural = actions or skills, recall without conscious effort, automatic actions through practice
• types of LTM evaluation:

  strength:

  • HM and Clive Wearing: episodic memory was impaired due to brain damagem, semantic memory and procedural was unaffected. Clive = remembered how to play piano and read music - supports different memory stores in LTM
  • real-world application to help treat individuals, age increase the episodic memory goes - target specific treatment

  weakness:

  • clincal studies have a lack of control variables, cannot have control before or after the injury, so you cannot see memory before damage
• WMM: Baddeley and Hitch (1974) explanation of how STM is organised and how it functions.

  • central executive = monitors incoming data and divides our attention
  • phonological loop = deals with auditory information and preserves order in which it arrives in
  • visuo-spatial sketchpad = stores visual or spatial information
  • episodic buffer = temporary store for information, recording events - links to working memory to LTM
• WWM:

  • central executive has a limited processing capacity
  • phonological loop has a capacity of 2 seconds
  • visuo-spatial sketchpad has a limited capacity
  • episodic buffer has a limited capacity
• Murdock: participants showed list of 10-40 words, then asked to recall them in no order

  • likeness of a word being recalled depended on the position in the list (serial position curve)
  • words earlier or later on in the list were recalled more often than the ones in the middle
• serial position curve: the accuracy of recall is affected depending on the position of an item in a sequence. - tested by Murdock
• murdock evaluation:

  strength:

  • supported by MSM - rein forces idea that there are two different stores of memory
  • study was standardised - easy to replicate, high internal validity as the same procedure was used for each participant

  weakness:

  • lack of mundane realism, memorising lists of words is not an everyday thing