02 Declarative Memory

Aka smRti.

Procedural vs declarative knowledge

Knowledge can be declarative or procedural depending on whether it is stored using some language (which may include words, sounds, pictures, videos, touch, taste etc..); here we are concerned with the former kind. Procedural memory is considered separately.

Importance

Memory (short and long term) is fundamental to computation (mechanical or animal). Like thoughts, memory is like a mosaic, rather than linear.

Classification, uses

Depending on how quickly stored information (memory) is forgotten, memory is classified into short and long term. Activation of long term memory is crucial in innovative thought.

Important, frequently used information is stored for a long time.

Acquisition of procedural memory is considered elsewhere.

Working memory

Most people can hold 2-4 items in their memory. Working memory is fundamental to attention and behavior inhibition.

Exceeding this limit results in cognitive overload. So, prioritizing and picking information to store is critical. \experience{This may be accomplished by a process of repeated summarization.}

Greater working memory implies greater speed. It also entails stronger ability to recover attention towards a goal from distractions.

Memory updates with recall

As an memory is recalled, the memory stored in the brain is modified.

For example, 1] Whenever we remember a face, we actually reconstruct picture of the face. 2] in one case a rape victim in trying to identify the rapist from a lineup merged the memory of a similar face with the memorized face of the rapist.

Long-term storage techniques

General knowledge acquisition techniques are considered elsewhere. Memory champions use “strategies for encoding information with the sole purpose of making it more memorable”.

Long term storage necessarily requires paying attention to the material.

Location method

Location method is also the technique to remember lists of objects where one, in imagination, places objects in different parts of a structure (eg: a room).

Mnemonics

Mnemonics are short, easier-to-remember sounds used to remember larger sentences and lists.

Number memory

Some memorize a simple image to associate with each of the two-digit combinations from 00 to 99 — one of the most basic techniques in the mnemonist’s tool kit.

Exercises

Working harder while getting the information helps with storing memory - like associating it with previous ideas or using deliberately hard text.

Repetition

Spaced repetition strengthens memory. So, interleaving different information to be stored helps.

With retrieval practice, one tests and updates one’s memory with attempts at recall. Retrieving a memory makes it stronger.

Recall techniques

Recall is a form of thought, and has an associative/ mosaic nature.

Priming

With priming, one exploits the social nature of the brain’s working to access long-term memory. To remember something related to what happened while playing cricket, it helps to crouch into the posture adapted while playing cricket.

Conneciton with age

Stored memory does not dissipate during most of peoples’ lives, but quickness in recall declines after youth. Storing ability may also decline. \tbc

Effect of external memories

With the advent of tools such as written books and computers, there is a (cultural and possibly biological) decline in accurate memorization and recall techniques. Eg: oral poetry in multiple cultures has declined.