I was very surprised to learn that there are actually three types of memory. According to Multimodal Learning Through Media: What the Research Says, these are: working memory, sensory memory, and long-term memory.
Working memory is where thinking gets done. It is dual coded with a buffer for storage of verbal/text elements and a second buffer for visual/spatial elements. Working memory is short-term and limited to approximately four objects that can be simultaneously stored in visual/spatial memory and approximately seven objects that can be simultaneously stored in verbal short-term memory. [Keep in mind that these ‘objects’ could be very large and complex schemas.]
If the person shifts attention when those buffers are full, new elements may be introduced into working memory, causing others to disappear from thought/consciousness. This is called an attention blink!
As trainers, we have known for a long time that the more senses engaged, the more likely the learning will be retained. We work to engage as many senses as possible through vivid stories or visualizations, meaningful metaphors, and participatory learning activities. Neurological research now explains that if a number of senses provide input to working memory at the same time, this convergence will have a positive effect on memory retrieval. It creates linked memories, so that triggering any aspect of the experience will bring to consciousness the entire memory, often with context.
Sensory memory occurs when we experience any aspect of the world through our senses. A sensory experience is involuntarily stored as episodic knowledge in long-term memory. We need to pay attention to sensory memory episodes for them to get introduced into working memory. Once the experience is in working memory, we can consciously hold it in memory and think about it in context.
Long-term memory in humans is estimated to store the equivalent of 50,000 times the text in the U.S. Library of Congress. The brain has two types of long-term memory, episodic and semantic:
Episodic memory comes directly from sensory input and is involuntary.
Semantic memory stores the thinking accomplished in working memory, such as ideas, thoughts, schema, and processes. The processing in working memory automatically triggers storage in long-term memory.
How the brain works has direct implications for effective training design.
Next week, we will conclude our discussion of multimodal learning with a look at three key principles that should be considered when designing learning.