Cognitive Psychology: Baddeley’s WM

Introduction to Memory Models

• Human memory is commonly modeled as a three-box system: sensory memory, short-term memory, and long-term memory.

• Sensory Memory: Captures brief impressions of the world, allowing for initial processing of sensory information.

• Short-Term Memory: Temporary storage for information that is currently being processed; this capacity is limited.

• Long-Term Memory: Stores information indefinitely, encompassing all memories that a person can access later.

Limitations of the Three-Box Model

• Oversimplification: The three-box model primarily explains learning and memory but does not account for ongoing cognitive processes occurring in real time.

• Dynamic Memory Processing: Cognitive tasks are often running in the background, similar to a computer's multiple processes, indicating that short-term memory cannot fully capture our immediate cognitive activities.

The Shift from Short-Term Memory to Working Memory

• The evolution of memory models includes the move from short-term memory to the concept of Working Memory, which provides a more nuanced understanding of how we manipulate and use information in real-time.

• Parallel Distributed Processing: Suggests that the brain processes multiple streams of information simultaneously rather than in a linear fashion.

Factors Affecting Short-Term Memory

• Two key factors influencing how we remember information:

  • Pronunciation Time: The duration taken to pronounce a word impacts its memorability. Shorter words are generally easier to recall than longer, more complex ones.

    • Example Exercise: Two lists of country names showed that people generally remember shorter, simpler names better (e.g., "Burma, Greece, Tibet" vs. "Switzerland, Nicaragua, Botswana").

  • Semantic Similarity: Words with related meanings may interfere with each other in memory recall, impacting how well items can be remembered.

    • Proactive interference occurs when older memories interfere with new memory formation, especially when items share semantic features.

Research Insights on Memory

• Christopher Wickens' Studies: Found that items from different semantic categories are easier to recall compared to similar-sounding or related items by testing memory under conditions where participants had to recall letter strings while engaged in a secondary task.

  • Release from proactive interference occurs when the final items presented differ semantically from prior items.

The Working Memory Model by Alan Baddeley

• Baddeley and Hitch introduced the Working Memory Model in the early 1970s, which includes several distinct components:

  • Phonological Loop: Responsible for the processing and storage of verbal and auditory information.

  • Visuospatial Sketchpad: Handles visual and spatial information, enabling navigation and visual memory tasks.

  • Central Executive: Acts as the manager, coordinating activities between the phonological loop, visuospatial sketchpad, and long-term memory while suppressing irrelevant information.

  • Episodic Buffer (added later): Integrates information across the various components and connects working memory with long-term memory.

Describing the Components of the Working Memory

• Phonological Loop

  • Limited capacity for sound information.

  • Active during tasks involving auditory memory and processing.

  • Involved in phenomena like the recency effect in memory recall.

• Visuospatial Sketchpad

  • Manages visual and spatial information, allowing one to visualize and interact with the environment.

  • Engages in tasks like navigating, drawing, or mentally visualizing scenes.

  • The right hemisphere is significantly involved in these processes.

• Central Executive

  • Functions as the system's CEO, overseeing and allocating resources to the various memory subsystems.

  • Does not have its own capacity but uses resources from the phonological loop and visuospatial sketchpad.

  • Facilitates attention, problem-solving, and decision-making.

Conclusion

• The concept of working memory provides a comprehensive framework to understand how we process, hold, and manipulate information in real-time, as opposed to just storing it passively.

• This model emphasizes the dynamic and multifaceted nature of human cognition, moving away from the oversimplistic three-box approach.