Working Memory Model Flashcards

Working Memory Model (Baddeley & Hitch, 1974)

Overview

  • The Working Memory Model (WMM) was proposed as an alternative to the Multi-Store Model (MSM) to better explain the complexities of short-term memory (STM).
  • WMM posits that STM consists of multiple active stores rather than a single unitary store as suggested by the MSM.
  • Key components:
    • Central Executive
    • Phonological Loop
    • Visuo-Spatial Sketchpad
    • Episodic Buffer (added in 2000)

Components

Central Executive

  • Function: Attentional control system that manages cognitive processes by directing information to other components.
  • Coding: Modality-free, processes information from any sensory modality.
  • Capacity: Limited; can handle one strand of information effectively at a time.

Phonological Loop

  • Function: Processes auditory information, preserving the order of information.
  • Sub-components:
    • Phonological Store (Inner Ear): Stores acoustic information for a short duration (1-2 seconds).
    • Articulatory Control Process (Inner Voice): Rehearses verbal information to prevent decay, with a time-based capacity (approximately 2 seconds).

Visuo-Spatial Sketchpad

  • Function: Stores visual and spatial information, including the relationship between objects.
  • Sub-components:
    • Visual Cache: Stores visual data relating to form and color.
    • Inner Scribe: Processes spatial information and transfers it to the central executive.
  • Capacity: Limited to about three or four chunks of information.

Episodic Buffer

  • Function: Integrates visual, spatial, and verbal information, maintaining a sense of time sequencing; links STM to long-term memory (LTM).
  • Coding: Auditory and visual information.
  • Capacity: Limited to about four chunks of information.

Dual-Task Performance

  • WMM explains dual-task performance by suggesting that if two tasks use the same component, performance will be impaired due to interference. If they use different components, they can be performed concurrently without significant interference.

Strengths

  • Supported by dual-task studies (Baddeley & Hitch, 1974) demonstrating the existence of separate visual and verbal processing components.
  • Brain imaging studies (Paulesu et al., 1993; Braver et al., 1997) provide evidence that different brain areas are activated during verbal and visuo-spatial tasks.
  • Case studies, such as patient KF, support the presence of separate STM components for visual and verbal information.

Weaknesses

  • Case studies may lack generalizability due to the uniqueness of individual brain injuries.
  • Studies may lack ecological validity as tasks are often unrealistic.
  • The model is simplistic concerning LTM.
  • The central executive is not well-defined and difficult to measure directly.

Applications

  • Helps explain multitasking capabilities and learning difficulties.
  • Provides insights into understanding amnesia.