milner

Evaluation of Milner (1966): The Case Study of HM (Bullet-Point Format)

Introduction

• Memory: A cognitive process involving encoding, storage, and retrieval of information.

• Hippocampus: A medial temporal lobe structure responsible for consolidating short-term memory into long-term memory.

• Approach relevance:
  

  • Supports the cognitive approach through insights into memory models.

  • Supports the biological approach by linking brain structures to behavior.

• Essay focus: Evaluation of Milner’s (1966) study using the TEACUP framework: Testability, Empirical support, Applications, Construct validity, Unbiasedness, and Predictive validity.

Theory

• Supports the Multi-Store Model of Memory (Atkinson & Shiffrin, 1968): distinct memory stores (STM and LTM).

• Demonstrates localization of function: the hippocampus is crucial for forming new long-term memories.

• Differentiates between explicit (declarative) and implicit (procedural) memory systems.

Evidence

• Aim: Investigate the role of the hippocampus in memory formation.

• Method:
  

  • Longitudinal case study (50+ years).

  • Method triangulation: IQ tests, interviews, memory tasks, MRI scans.

• Findings:
  

  • HM had anterograde amnesia: unable to form new explicit long-term memories.

  • Retained short-term memory and procedural memory (e.g., mirror drawing).

  • MRI scans (Corkin, 1992 & 2003) revealed hippocampal and medial temporal lobe damage.

Application

• Demonstrated memory is not unitary: different brain systems for different types of memory.

• Informed treatments for amnesia and neurodegenerative conditions like Alzheimer’s.

• Encouraged use of neuroimaging techniques (e.g., MRI) in cognitive neuroscience.

Criticism

• Low generalizability: Findings based on one individual.

• Retrospective limitations: Lack of pre-surgical baseline data.

• Confounding variable: Anti-epileptic medication may have influenced cognitive function.

Unanswered Questions

• To what extent can neuroplasticity allow compensation by other brain areas?

• How are semantic and episodic memory differently affected by hippocampal damage?

Practical Use

• Influenced neurosurgical practices: highlighted risks of removing medial temporal structures.

• Supported rehabilitation strategies: focused on preserved memory systems (e.g., implicit learning).

Counterarguments

• Clive Wearing: Similar case reinforces HM’s findings—damage to hippocampus leads to profound amnesia.

• Alternative models:
  

  • Working Memory Model (Baddeley & Hitch, 1974) suggests a more dynamic view of memory than the linear Multi-Store Model.

Conclusion

• HM’s case provides strong empirical support for the role of the hippocampus in memory consolidation.

• Despite methodological limitations, it remains highly influential in both cognitive and biological psychology.

• Future research should explore interactions between memory systems and intervention strategies for memory disorders.