Study Notes on Memory and the Multi-Store Model

MEMORY

Lesson 4 - Multi-Store Model

Topic Overview

  • Introduction to memory: Overview of memory as a mental process that encodes, stores, and retrieves information.
  • Baddeley and encoding: Focus on how information is encoded in memory.
  • Types of Long-Term Memory: Explore various forms in which information can be stored long-term.
  • Multi-Store Model: Introduction to Atkinson and Shiffrin’s model of memory with its distinct stores.
  • Murdock’s Research: Examination of Murdock's investigations into memory storage.
  • Bartlett’s research: Study of reconstructive memory through Bartlett’s experiments.
  • Reconstructive Memory: How memories can change over time through external influences.
  • Memory Interference: Discussion of how memories can interfere with each other.
  • Context-Dependent Memory: The impact of the environment on memory recall.
  • False Memories: Exploration of incorrect recollections of past events.

Lesson Objectives

  • To describe features of the Multi Store Model: Detailed understanding of the components and characteristics of the model.
  • To explain real life memory examples using the Multi Store Model: Application of theoretical knowledge to everyday situations.
  • To discuss strengths and weaknesses of the Multi Store Model: Evaluation of the model's effectiveness and limitations.

Information Flow in Memory

  • Sensory Memory: Initial stage where sensory information is stored briefly.
  • Attention: Critical for transferring information from sensory to short-term memory.
  • Short-Term Memory (STM): Temporary storage requiring rehearsal to maintain.
  • Rehearsal: The technique used to keep information in STM and help transition to LTM.
  • Long-Term Memory (LTM): Storage of memory that can last a lifetime and may hold unlimited information.

The Multi-Store Model (Atkinson and Shiffrin)

  • Components:
    • The model posits that memory consists of three distinct and sequential stores:
    • Sensory Memory
    • Short-Term Memory
    • Long-Term Memory
  • Differences among the stores:
    • Capacity:
    • STM: Limited, typically 7 ± 2 items.
    • LTM: Potentially unlimited.
    • Duration:
    • STM: Brief, average of 18 seconds.
    • LTM: Long-lasting, potentially over 48 years.
    • Encoding:
    • STM: Primarily acoustic (sound-based).
    • LTM: Primarily semantic (meaning-based).

Definitions

  1. Capacity: The maximum amount of information that can be held in memory.
  2. Duration: How long information can be retained in memory.
  3. Encoding: The process through which information is translated into a format that can be stored in the brain.

Differences between STM and LTM

  • Capacity:
    • STM: 7 ± 2 items.
    • LTM: Potentially unlimited.
  • Duration:
    • STM: Average of 18 seconds.
    • LTM: May last a lifetime (+48 years).
  • Encoding:
    • STM: Acoustic.
    • LTM: Semantic.

Visual Representation of the Multi-Store Model

  • The model reflects a linear flow of information through the three distinct memory stores.
  • Information is transferred from sensory memory to short-term memory via attention, and from short-term memory to long-term memory via rehearsal.

Fill out the Memory Characteristics

  • Sensory Memory:
    • Coding: Senses (touch, smell, sight, taste, sound)
    • Capacity: High (almost limitless)
    • Duration: Very brief, less than half a second.
  • Short-Term Memory (STM):
    • Coding: Acoustic
    • Capacity: 5 – 9 pieces of information
    • Duration: Up to 30 seconds (18 seconds average)
  • Long-Term Memory (LTM):
    • Coding: Semantic (meaning)
    • Capacity: Unlimited
    • Duration: Lifetime (+48 years)

Strengths of the Multi-Store Model

  • Neuroscientific Support:
    • Brain scans (e.g., fMRI) show different brain areas are activated for STM and LTM tasks.
    • Prefrontal cortex: Active during short-term memory tasks.
    • Hippocampus: Active during long-term memory tasks.
  • Evidence from Case Studies:
    • Case study of individual H.M., who lost the ability to form new memories following hippocampus removal, supporting the distinction between STM and LTM.
  • Controlled Studies: Numerous lab studies demonstrating the capacity, coding, and duration of memory stores.
  • Support from Baddeley (1966): Affirmation that STM and LTM are indeed different through experimental findings.

Limitations of the Multi-Store Model

  • Rehearsal Not Solely Responsible:
    • Research indicates that simple rehearsal does not guarantee memory retention.
    • Craik and Lockhart (1972) suggest memory is formed by deep processing, not merely through rehearsal.
  • Shallow vs. Deep Processing:
    • Craik & Tulving (1975): Participants remembered more words when required to engage in deep processing (semantic) compared to shallow processing (structural).
  • Non-Unitary Nature of Memory Stores:
    • The model oversimplifies memory by treating STM and LTM as unitary, while other models (like the working memory model) discuss multiple components.
    • Example: Clive Wearing demonstrates different functioning in memory systems.
  • Lack of Ecological Validity:
    • Lab studies often lack relevance to real-life memory use, utilizing meaningless materials (e.g., consonant syllables) and lacking everyday context.
    • However, these studies do maintain higher control, promoting clearer cause-and-effect relationships.

Exam Question

  • Describe and evaluate the multi-store model of memory (9 marks):
    • Understanding the structure, functionality, strengths, and criticisms of the Multi-Store Model is essential for answering this question effectively.