Case Studies Supporting the Multi-Store Model

This page presents several important case studies that provide evidence for the multi-store model of memory and its components.

HM Case Study

HM experienced problems with long-term memory after brain surgery, while his short-term memory remained intact. This case supports the idea that short-term and long-term memory are separate systems, as proposed by the multi-store model.

Highlight: The HM case study is one of the most famous in neuroscience and has significantly contributed to our understanding of memory systems.

Clive Wearing Case Study

Clive Wearing suffered damage to his memory but could still perceive the world around him and play the piano. This case provides evidence that:

1. Short-term memory (STM) and long-term memory (LTM) are separate
2. The multi-store model's sequential process is valid, as Wearing couldn't store new memories

Example: Clive Wearing could play the piano, demonstrating intact procedural memory, but couldn't form new episodic memories.

Patient KF Case Study

Patient KF was involved in a motorbike incident and could retrieve from LTM but had problems with STM. This case suggests:

1. Information is stored acoustically in STM, as this was what KF had difficulty with
2. There may be another element to STM, as KF could remember visual information
3. The multi-store model of memory might be oversimplified

Vocabulary: Acoustic encoding refers to the process of converting information into sound-based representations for storage in memory.

These case studies provide valuable insights into the structure and functioning of memory, supporting some aspects of the multi-store model while also highlighting its limitations.

Characteristics of Memory Stores and Supporting Studies

This page delves into the specific characteristics of each memory store and presents key studies supporting the multi-store model of memory.

Characteristics of Memory Stores

1. Sensory Register:

   • Duration: milliseconds
   • Capacity: very large
   • Encoding: sense specific

2. Short-term Memory:

   • Duration: 18 seconds
   • Capacity: 7±2 chunks of information
   • Encoding: acoustic

3. Long-term Memory:

   • Duration: lifetime
   • Capacity: unlimited
   • Encoding: semantic

Vocabulary: Encoding refers to the process of converting information into a form that can be stored in memory.

Supporting Studies

1. Peterson and Peterson (1959):

   • Found that information is quickly lost from short-term memory without rehearsal
   • 24 psychology students memorized trigrams and were prevented from rehearsing
   • After 18 seconds, only 10% recalled correctly

2. Bahrick (1975):

   • Studied long-term memory duration by testing recall of ex-classmates' names
   • Free recall declined most within 30 years
   • Name recognition was better than photo recognition
   • Showed that information in long-term memory is hard to retrieve but forgetting is slow

3. Miller (1956):

   • Investigated short-term memory capacity using a digit span test
   • Found average capacity was 7±2 chunks of information

Example: The capacity of short-term memory is often demonstrated by asking people to remember a string of numbers, like a phone number.

These studies provide crucial evidence supporting the multi-store model's assertions about the characteristics and functioning of different memory stores.

Evidence for Different Types of Long-Term Memory

This page presents evidence supporting the distinction between different types of long-term memory, particularly focusing on studies of patients with amnesia and brain imaging research.

Amnesia Studies

Patients with amnesia provide evidence that procedural memory is separate from semantic and episodic memory:

1. HM Case Study (continued):
   • After hippocampus removal, episodic memory was affected
   • HM could improve at drawing a star, showing intact procedural memory

Highlight: The HM case study demonstrates the dissociation between procedural memory and other types of long-term memory.

2. Patient PM:
   • Lost memory due to a virus
   • Couldn't remember past or plan future (impaired episodic memory)
   • Recognized care worker and could learn new musical pieces
   • Suggests musical memory may be stored independently of other memory types

Brain Imaging Studies

Buckner and Peterson's research found:

• Semantic memory retrieval occurs in the left side of the brain
• Episodic memory retrieval occurs in the right side

Vocabulary: Dissociation in psychology refers to the separation of normally related mental processes, resulting in a lack of connection in a person's thoughts, memories, feelings, actions, or sense of identity.

This evidence supports the idea of different types of long-term memory and suggests that they may be processed in distinct brain regions. However, it's important to note that this research also challenges some aspects of earlier theories about the localization of memory functions in the brain.

Applications and Implications of Memory Models

This final page discusses the practical applications and broader implications of the multi-store model and working memory model in various fields.

Educational Applications

1. Multi-store model:

   • Emphasizes the importance of rehearsal for long-term retention
   • Informs study techniques like spaced repetition

2. Working memory model:

   • Helps explain individual differences in learning capacity
   • Informs strategies for presenting information in multiple modalities

Example: Teachers might use visual aids alongside verbal explanations to engage both the phonological loop and visuo-spatial sketchpad, potentially enhancing learning.

Clinical Applications

Both models have implications for understanding and treating memory disorders:

• Helps in diagnosing specific memory impairments
• Informs rehabilitation strategies for patients with memory deficits

Highlight: Understanding these memory models is crucial for developing effective interventions for conditions like Alzheimer's disease and amnesia.

Cognitive Research

These models have spurred further research into:

• The nature of consciousness
• The relationship between attention and memory
• The neural basis of memory processes

Vocabulary: Neuroplasticity refers to the brain's ability to change and adapt as a result of experience, which is crucial for memory formation and learning.

While these models have their limitations, they continue to be influential in shaping our understanding of human memory and cognition, driving ongoing research and practical applications in education, clinical psychology, and cognitive science.