Module 2.3 Memory

Memory is the persistence of learning over time, involving encoding, storing, and retrieving information as a complex system.

Measurement of Memory (2.3-1)

  • Memory retention is measured by:

    • Recall: Retrieving information without cues (e.g., fill-in-the-blank).

    • Recognition: Identifying previously learned items from options (e.g., multiple-choice).

    • Relearning: Measuring time saved when re-learning material, with the savings score indicating memory strength.

Memory Models (2.3-2)

  • Atkinson-Shiffrin Model: Proposes three stages:

    1. Sensory memory: Brief, initial recording (e.g., iconic ~<0.50.5s visual, echoic 3−43-4s auditory).

    2. Short-term memory (STM): Holds ~7extitemshinspaceextforhinspace15−307 ext{ items} hinspace ext{for} hinspace 15-30s without rehearsal; chunking increases capacity.

    3. Long-term memory (LTM): Permanent, limitless store (explicit for facts/experiences, implicit for skills).

  • Updated models:

    • Working memory: Active system replacing STM for processing information in complex tasks, involving a central executive, phonological loop, visuospatial sketchpad, and episodic buffer.

    • Automatic processing: Unconscious encoding of incidental information, contrasting with effortful processing.

Biological Basis of Memory (2.3-3)

  • Long-term potentiation (LTP): Increased efficiency in synaptic transmission after rapid stimulation, strengthening neural connections.

  • Factors:

    • Neurogenesis: Birth of new neurons, especially in the hippocampus.

    • Neurotransmitters: Glutamate (LTP), Acetylcholine (encoding), Adrenaline (emotional events).

    • Brain structures: Hippocampus/frontal lobes (explicit), Cerebellum (implicit), Basal ganglia (procedural).

Key Concepts

  • Neuroplasticity: Brain's ability to change and reorganize, underlying memory formation.

  • Memory is not stored in single locations but across interconnected neural networks, reactivated during recall.