Human Memory II

2-3 Minute Read

Author: Bruce Morgenstern, MD

Purpose

Establish an understanding of the processes of memory and memory formation to assist in promoting student learning so that teaching faculty are better prepared.

Learning Objectives

1. Discriminate between different steps in memory formation;

2. Expunge the analogy between human memory and computer memory – especially recall of memories; and

3. Appreciate-in more detail-the role of genes in generating long term memories.

Let’s dig just a bit deeper into what we believe we know about human memory.

A “simple” model based on the Atkinson–Shiffrin(1) model.

Of course, who really likes “simple” models?

This more expanded version,

Adapted from Figure 9.2 Types of Memory (2) and Memory Graphic (3)

You may be curious, so we’ll slake that curiosity, certain in the knowledge you’ll forget anyway!  Explicit memory usually refers to those memories that can be evoked consciously, and is often called declarative memory.  Episodic memory is recall of events, such as a specific birthday or a trip.  Semantic memory is the storage of factual information, such as the meaning of words or general knowledge (furosemide is a potent diuretic).

Implicit memory refers to the movement of the body in using objects, like riding a bicycle.  Procedural memory is probably the largest subset of implicit memories, a set which also includes associative and non-associative memories. Priming involves both the association between two stimuli that the subject has encountered together frequently or recently and the influence that activation has on the person’s behavior.(2) Learning Through Classical Conditioning involves Pavlovian responses to neutral stimuli.(2)

We will return to the issue of memory versus learning. One way to think about this is that if a long-term memory has been created and retrieved, it’s been learned. Remember the image below? In Human Memory 1, we presented it with both panels a and b. Panel a shows another sequence for memory formation, of course now in drosophila, which is why panel b had gene names (for genes associated with memory) like radish and rutabaga and amnesiac [We didn’t make this up].(4)

Adapted from Figure 1 (4)

It’s important to explain the initials to better understand the figure: STM = short-term memory, ITM = intermediate-term memory, ARM = anesthesia-resistant memory, LTM = long-term memory. “Observed” represent “lost” memory.  Drosophila, like us humans, forget.

We can’t not touch on the topic of memory palaces, but there really is not much published on the Medical Education literature, perhaps because there is a sort of binge-purge aspect to this tool:

https://archive.nytimes.com/well.blogs.nytimes.com/2014/05/19/remembering-as-an-extreme-sport/■

References

1. Atkinson R, Shiffrin R. Human memory: a proposed system and its control process. In: Spence K, Spence J (eds). The Psychology of Learning and Motivation. Vol 2. New York Accademies Press; 1968. pp 89-195. https://doi.org/10.1016/S0079-7421(08)60422-3

2. Stagor C, Walinga J.9.1 Memories as types and stages. In: Introduction to Psychology. BC Open Textbook Project; 2014. Accessed November 28, 2022. https://opentextbc.ca/introductiontopsychology/chapter/8-1-memories-as-types-and-stages/

3. Queensland Brain Institute. Types of memory. Accessed November 22, 2022. https://qbi.uq.edu.au/brain-basics/memory/types-memory

4. Tully T, Bourtchouladze R, Scott R, Tallman J. Targeting the CREB pathway for memory enhancers. Nat Rev Drug Discov. 2003;2(4): 267-277. doi:10.1038/nrd1061