by Dr. Julie Schwartzbard, MD
Memories are information that is taken into your brain and stored. The process of memory-making is second nature to your brain but the specifics of how it works are still mysterious to us. We do know that there are three basic functions that allow information to become a memory:
1. Acquisition — you learn or experience something new.
2. Consolidation — the memory of the acquired information lodges in your brain.
3. Recall — after “sleeping on it,” your brain allows indefinite access to the memory of that information now, and in the future.
While there are several subsets, there are two main types of memory: short term memory (STM) and long term memory (LTM). These two work together to absorb, store and recall information.
Short term memory
STM is a temporary process that sets off specific “firing” patterns in the neurons in your brain’s prefrontal lobe. All memories start as STMs. When the same neuronal firing pattern is repeated, the brain then stores that information as an LTM for retrieval later though some information never makes it that far.
When information is in the STM stage — only about 30 seconds long — you can only recall it when that specific firing pattern is active. It’s sort of like a chain reaction associated with a specific collection of mini information events. But information in this stage is not stored forever. Instead, you only remember it right then when the same neuronal firing is
happening. If the information is not repeated during STM, because of a distraction or interruption, that information may be lost for good, never becoming LTM.
Long term memory (LTM)
LTM is memory that you keep indefinitely. It’s stored, used and retained — sort of like food you keep in the fridge, take out for a while and then put back in to eat later. The hippocampus near the center of the brain turns STM into LTM and makes memories “stick.” The neocortex on the outer surface of the brain stores LTMs. Both repetition and emotional connections to information help create LTM, which is thought to be stored in the temporal lobes of the brain.
Other types of memory
In addition to STM and LTM, other types of memory are used to acquire and maintain all the different types of knowledge your brain uses and stores.
- Working memory
Often used interchangeably with STM, working memory includes verbal and visual information along with the functions that manage STM. “Working memory is your brain’s Post-it™ note,” says Tracy Packiam Alloway, PhD, at the University of North Florida in Jacksonville, Florida. “It makes all the difference to successful learning.”
- Conscious memory
Conscious memory is what your brain knows and is able to find, retrieve and produce when you need it. The brain holds a lot more information than you’re consciously aware of or could ever access.
- Subconscious memory
The thoughts, sensations and feelings that exist but are unavailable to your brain for instant retrieval make up most of subconscious memory.
- Explicit or declarative memory
Explicit memory is a part of conscious memory. It’s composed of information that you remember and know because it is based in fact: what you did last night, where you were born, and that Washington D.C. is the capitol of the US.
- Implicit memory
This type of memory is experience-based and refers to knowledge you retain without thinking about it, especially behaviors and actions. It includes procedural memory which is used for things like reading or riding a bike.
- Immediate memory
As you might expect, immediate memory is information that’s only stored for a few seconds, like sounds or a short number sequence, though its span can vary from person to person.
The mystery of remembering — and forgetting
The memory-making process allows you to remember a nearly endless stream of important, and sometimes not-so-important, information. The hippocampus processes memories but they can be stored in several parts of the brain including the visual cortex, the language areas and the motor cortex. This explains why you can lose certain pieces of memory if there is an injury to the part of the brain where they’re stored.
It’s confounding when you’re desperately trying to pin down a memory, but the process of recalling can be very selective. Wrong or right, your brain will make the final decision about whether it’s important to remember something — or someone — or not. Some people have memories of traumatic events that they’d rather not recall. And sometimes, something good ends up connected to a bad memory, and your brain won’t categorize that good thing as positive anymore.
But even with all its quirks and curiosities, your memory is a wonder. Each day it registers, processes, categorizes and stores endless amounts of information, and retains most of it. When your memory is working properly, you can recall information from its deepest recesses.
Many factors affect and influence your ability to remember, either negatively or positively. From my research and experience as a practicing neurologist, I know what you can do today to preserve and enhance your memory now, and for the future. The memory-supporting factors most in your control are lifestyle, diet and nutrition. It’s easy to provide your brain with the specific nutrients known to work to enhance and improve memory with my exclusive Memory Solutions. Find out more now.
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