Psych Boost: Memory Unit Lecture

Overview of Memory Unit

• Six-part series covering memory models and topics.
• Focus on:
  • Models of memory
  • Types of long-term memory
  • Reasons for forgetting
  • Eyewitness testimony and improvements
• Related to the cognitive approach in psychology.

Multi-Store Model (MSM) of Memory

Introduction to MSM

• Developed by Atkinson and Shiffrin (1968)
• Linear information processor model
• Passive stores: Sensory register, short-term memory (STM), long-term memory (LTM)
• Key features to remember:
  • Coding: Format of stored information
  • Capacity: Amount of information that can be held
  • Duration: Time information can be held

Sensory Register

• Directly receives sensory information.
• Coding: Modality specific; different for each sense (iconic, auditory, etc.).
• Capacity: Very large, potentially unlimited.
• Duration: Very short (approx. 250 milliseconds).
• Transfer to STM: Through attention.

Short-Term Memory (STM)

• Coding: Acoustic
• Capacity: 7 items (±2)
• Duration: 18 to 30 seconds
• Information loss: Due to displacement or decay.
• Transfer to LTM: Through rehearsal (maintenance or elaborative).

Long-Term Memory (LTM)

• Coding: Semantic
• Capacity and Duration: Very large, potentially unlimited.
• Information not truly lost, but access may be difficult without cues.

Evaluations of MSM

Research Evidence

• Glanzer & Cunitz (1966): Primacy and recency effect - supports separation of LTM and STM.
• Sperling: Sensory register capacity - large capacity demonstrated through iconic memory tests.
• Baddeley: Coding in STM and LTM - worse recall for acoustically similar words suggests acoustic coding in STM.
• Jacobs (1887): STM capacity - 7±2 items; shows small STM capacity.
• Miller: Chunking increases STM capacity.
• Peterson & Peterson: STM duration - 18 to 30 seconds, tested using trigrams.
• Wagenaar & Bahrick: LTM capacity/duration - very large; diary studies and recognition tasks show high recall across years.

Additional Evaluations

• Artificial Testing: Questions about ecological and mundane realism of lab studies.
• Inferences: Experiments rely on inferences; possibility of wrong conclusions.
• Evolutionary Perspective: Justifies sensory register's large capacity and short duration for survival.
• Simplicity of MSM: Criticized for being too simplistic; research shows multiple LTM types and active STM components.
• Face Validity: MSM assumptions do not always hold true (e.g., LTM of tastes, variable STM capacity).

Conclusion

• MSM provides a foundational understanding of memory processes but has limitations.
• Next video will focus on types of long-term memory.

• Study Tip: Draw the MSM diagram and table for coding, capacity, and duration for each store to aid recall.
• Patreon Support: Access additional resources and video tutorials for deeper understanding.

• Follow-Up: Watch related cognitive approach videos for broader context and understanding.