Modal Model of Memory Notes

Modal Model of Memory

Memory Process (5 Steps)

  • Sensory Input: Information from the environment (light, sound) enters through senses (eyes, ears) and is briefly held in sensory memory.
  • Short-Term Memory (STM): A small portion of sensory information moves to STM, held briefly, especially with rehearsal.
  • Rehearsal: Repeating information keeps it active in STM and aids transfer to long-term memory.
  • Long-Term Memory (LTM): Information stored here can last a long time. Retrieval brings it back to STM.
  • Forgetting: Information can be lost from any memory store due to decay or interference.

Key Features

  • Three independent memory stores: sensory, STM, LTM.
  • Differ in capacity, duration, and encoding format.

Encoding

  • Encoding: Changing information for storage in memory.
    • Visual (picture)
    • Acoustic (sound)
    • Semantic (meaning)
  • Capacity: How much information can be stored.
  • Duration: How long information lasts in memory before loss or transfer.

Sensory Memory

  • Holds information about a perceived external stimulus for a fraction of a second after it disappears.
  • One sensory register per sensory system.
    • Iconic memory: momentary storage of visual information
    • Echoic memory: momentary storage of auditory information
  • Encoding Format: A copy of input as received by the senses (image, sound, touch).
  • Capacity: Large; 25+ stimuli stored simultaneously.
  • Duration: Very brief; 14\frac{1}{4} - 2 seconds.
  • Information that is attended is transferred to STM; the remainder decays rapidly

Studying Sensory Memory

  • Demo #1: Measuring Iconic Memory – Whole Report Technique (George Sperling, 1960)
    • Used to test the capacity of visual sensory memory
    • Participants are asked to recall all of the presented data, such as a string of letters or numbers
  • Demo #2: Measuring Iconic Memory – Partial Report Technique (George Sperling, 1960)
    • Testing memory in which only some of the total information presented is to be recalled

Short-Term Memory (STM)

  • Information from sensory registers that is attended to moves into STM.
  • Capacity: Holds a small amount of information (limited capacity of approximately 7 items) for a short period of time (limited duration of approximately 20–30 seconds).
  • Duration: If material is rehearsed then it can be maintained in STM for a longer period (e.g., chanting a phone number until it is dialled = maintenance rehearsal)
  • Encoding format: visual, auditory, or semantic

Long-Term Memory (LTM)

  • Encoding format: The representation of facts, images, actions, and skills.
  • Duration: May persist over a lifetime (potentially limitless duration).
  • Capacity: LTM is theoretically limitless.
  • Extracting information from LTM is called retrieval.

Evolution of Memory Models

  • Memory is no longer thought of in terms of a serial processing model
  • Memory is now thought to be comprised of a number of modules which are discrete but interdependent (parallel processing).