What is Memory?

Memory is the ability of an organism to retain, store, and recall past experiences and information.

There are three different stages of memory, these are: sensory, short-term, and long-term. Not everything is known about memory, and there is still a lot more to research.

Sensory Memory

After an object is received, approximately 200-500 milliseconds into the function, is what sensory memory corresponds to.

An example of this ability is being able to remember what an item looks like just a couple of seconds after viewing it.

There are different types of this memory, all of these lasting for a short amount of time and are not able to be recalled with clear precision, decaying over time.  

Short-term Memory

Short-term memory's capacity (like sensory memory) is also very limited, allowing a person to recall something for a period of a few seconds to a minute, without repetition or rehearsal.

A persons short-term memory capacity is said to be low, but can be improved with a technique called 'grouping'/'chunking'. This is where you split something into smaller more manageable sizes for your short-term memory to digest. For example: Someone gives you a number of 117342334. 

Instead of trying to learn the whole number off by heart, you would split it up to say: (117), (342), (334). Then you could (instead of naming these groups by there numbers, e.g. one, one, seven (117,)) name the three new numbers by there whole new numbers, e.g. one-hundred-and-seventeen, three-hundred-and-forty-two, three-hundred-and-thirty-four.

Herbert Simon found that the ideal 'grouping'/'chunking' size for numbers was three.

Short-term memory is believed to rely more on an acoustic code for retaining information, rather than, to an extent a visual code.

Long-term Memory

Whilst sensory and short-term memory have a limited capacity for retention and duration, long-term does not. This type of memory holds a far more vast quantity of information (some of these can last a lifetime).

With short-term memory, the likelihood of forgetting phone numbers, names, addresses and directions (and the like), is a probable circumstance. However, with long term memory (and techniques such as repetition), a huge amount of information can be catalogued inside the mind. For example: Lu Chao from China managed to recall off by heart 67,890 digits of pi! 

Baddely discovered (1966) that after 20 minutes, it was hardest to recall names, numbers, and words with similar meanings. (Big, large, huge; small, tiny, miniature, etc).