The way our brain stores, maintains and retrieves memory is a fascinating process. It is only recently that neuroscientists and academic researchers are beginning to really understand how this complicated process works. There are three primary ways we process incoming information: sensory memory, short-term (working) memory, and long-term memory.
- Sensory Memory – Sensory memory is used to describe our ability to retain impressions of information that come from our five senses. A sensory memory can exist for any of these sensory channels:
- Visual Memory | sight
- Auditory/Echoic Memory | hearing
- Haptic Memory | touch
- Olfactory Memory | smell
- Gustatory Memory | taste
Each of these memory types is important and deficiencies in any one of these can cause certain tasks to become more difficult. For instance, deficiencies in visual memory can affect your ability to read and write. Deficiencies in auditory memory can affect your ability to understand words or remember information that has been presented verbally.
One of the main factors that separates sensory memory from other types of memory is that this type of memory is usually stored in your brain for less than two seconds. This brief time window gives us just enough time to process, analyze and interpret the incoming message. If we deem the information important enough we move it on to the next type of storage.
- Short-term Memory/ Working Memory – When information is deemed important we move it from sensory memory to our short-term memory. When using short-term memory most humans can handle about seven pieces of information for about half a minute. We can extend this period if we “rehearse” the information by repeating the thoughts in our head, which helps it move to long-term memory. Most information is lost (forgotten) within short-term memory. The limits of short-term memory make it impossible for anyone to remember everything they experience. Even people with eidetic memory (photographic memory) cannot remember everything contrary to popular belief.
- Long-term Memory – If information is lucky enough to survive the first two stages it has a chance of getting processed and finds a home in your long-term memory. A common metaphor is that long-term memory is the brain’s library. Like a traditional library, information in long-term memory is sorted, filed, and indexed in a variety of ways. Because we are spatial creatures, and for the most part organize our lives based on time, our long-term memories are organized by date and time chronologically. Our brain’s long-term cataloging system is complex but is made up of three key components:
- Semantic memory: The portion of long-term memory which is concerned with formulating our ideas, meanings, and concepts.
- Procedural memory: The portion of long-term memory which helps us remember how to do things.
- Episodic memory: The portion of long-term memory which refers to our ability to recall personal experiences from our past.
Admittedly, this is a very cursory review of what makes up our memory and by no means is it exhaustive. Also, there are special definitions within memory that fall out of the realm of this three stage progression. For instance, priming is an aspect of memory that describes our subconscious mind’s increased sensitivity to certain information when we are exposed to it multiple times over a given time period. A real world example is your increased ability to remember a co-worker’s name better when you have heard it for the fifth time versus hearing it for the first.
Studies show that our memory gets better with practice, such as playing brain and memory games.