Capacity of Long Term Memory
Scientists say that our brain can hold up to 100 billion neurons. If we compare the human brain to a computer, scientists speculate the storage limitation is between 1 terabyte to 2.5 petabytes.
KB 1,000 bytes
MB 1,000,000 bytes
GB 1,000,000,000 bytes
TB 1,000,000,000,000 bytes
PB 1,000,000,000,000,000 bytes
But those are just numbers. What do they even mean?
One petabyte can store roughly, 13 years of HDTV content. Or as gizmodo says, 58,292 movies. In 2013, Google’s entire satellite mapping and 3-d viewing is 20 petabytes. The truth is, no one really knows the exact limits of a healthy fully developed human brain, and that scientists will agree that we won’t be running out of memory in one lifetime.
Life Span of Long Term Memory
Unfortunately, not all long term memories are created equal. A long term memory’s life span can range from a few days to decades. It all depends on how strong the memory was when it was created (how many hooks, cues, and other memories are attached to it), how many times it’s been traversed over (how many times it’s been revisited), and whether it’s been attached to newer memories. So whether or not you remember something ‘forever’, or until you die, is up to how you maintain your memories.
Leveraging Long Term Memory as a Tool
One of the two ‘super-tools‘ I’ve noticed the fastest learners of our time use is the question, “How is this something like I already know?”. It jogs their existing long term memory, making the new information easy to digest and store, and merges the two memories (new and old) together for quick access and better long term storage..
I highly recommend use it anytime you learn something new and leverage the power of existing long term memories.
Types of Long Term Memory
Long term memory can be broken down into Procedural Memory and Declarative Memory.
Procedural memory is remembering how to do things. Ride a bike, brush your teeth, drive a car, etc. Anytime you acquire a skill, it’s being stored in your long term procedural memory.
Declarative Memory, sometimes known as explicit memory, is when you remember what something is. It can be either semantic or episodic.
- Semantic memory is information stored about the world. Names of countries in the world, names of celebrities or people in your life, what your gender is, etc.
- Episodic memory is remembering something that happened in the past. It is where all of our memories about our past experiences and life events are stored. Typically when you hear someone say, “remember the time when…” they are accessing their long-term episodic memory.
Typically, when someone gets amnesia, they’re declarative memory is damaged but their procedural memory remains more or less intact. For example, in retrograde amnesia, people are unable to recall the past, but their skills set is roughly unaffected. Similarly, in anterograde amnesia, the person is no longer able to store declarative memories, but their procedural memory is once again roughly unaffected.