January 16, 2017

SAM Retrieval model

First described by Atkinson and Shiffrin.

Human memory has three components

  1. Sensory Register
  2. Short Term Store
  3. Long Term Store
┌──────────┐           ┌──────────┐           ┌──────────┐
│          │           │          │ Transfer  │          │
│ Sensory  │ Attention │Short Term│──────────▶│Long Term │
│  Store   ├──────────▶│  Memory  │           │  Memory  │
│          │           │          │◀──────────│          │
└──────────┘           └──────────┘ Retrieval └──────────┘

Sensory Register

  • When the environmental stimulus is detected by the senses, it is briefly stored in the Sensory Registers.
  • They act as buffers
  • There is one register for each of the senses
  • They donot process information

Visual System Sensory Register

  • Also called as Iconic memory
  • It is limited only by the field of vision
  • Information rapidly decays after 0.5 - 1.0 seconds

Auditory System Sensory Register

  • Also called as Echoic memory
  • Information retain duration is between 1.5 and 5 seconds, but can last upto 20 seconds in the absense of competing information

Short Term Store

  • Also called as working memory
  • Information processing happens here
  • The information in the Sensory Store that is attended to, is transfered to the Short Term Memory
  • Information lasts between 18-20 seconds
  • Information can be held longer by rehersal
  • The information in short-term memory need not be at the same modality as the Sensory Input
    • For ex: Visual Information can be stored as Auditory Information
  • It can hold around 7 +- 2 chunks at a time
    • Chunks are independent items of Information

Long Term Store

  • Also called as permanent memory
  • Memory in Long Term Store can be copied to Short Term Stoe, where it can attended to and manipulated
  • The transfer from STM to LTM occurs automatically, as long as the information is attended to in the STM
  • Nearly limitless in the duration and capacity

Retrieval of information

  • Memories stored in long-term store are retrieved by assembly of cues, sampling, recovery and evaluation of recovery
  • When an item has to be recalled from LTM, the user assembles various cues for the item in the STM
  • Using these cues the user determines which area of the LTM has to be searched
  • Items with the strongest association to the cue items are eventually recalled
  • Once the item is recalled, the user evaluates it
    • If the user believes it is match, then it is the output
    • If not the user restarts the process with different cue or weighting cues differently