In the second article of this series, we will see how the brain processes information.
All sensory information is screened for importance by a ‘sensory register’. If the information is unimportant, it is not processed. This is called sensory filtering. It occurs without the involvement of the conscious brain, and allows the conscious brain to focus on important things.
There are different stages of memory. Broadly, they may either be temporary (short-term), or permanent (long-term) memory.
Short Term Memory
- Immediate Memory
- Working Memory
This operates like a clipboard on a computing device- information is held here for a short time (up to 30 seconds), then dropped out of the system if it is of little or no importance. The operation may either be subconscious or conscious.
Example: You receive a One Time Password (OTP) to make a transaction, and need to enter it on the same device. Usually, you will be able to remember the number long enough to complete the transaction, after which the number drops out of immediate memory since it has no further importance.
This is a conscious temporary memory that can handle only a few things at the same time. The number of items that can be handled varies with age, and is between 5 to 9 (average 7) for adults.
Items in the working memory of adults can be intently processed for 10 to 20 minutes on average.
Example: You are in town, and a friend calls to request you buy some items on your way back. You repeat the items over the phone, and go shopping nearby, recalling the items on the list. Once your purchase is over, you forget the list.
A process called chunking allows one to increase the number of items within the functional capacity of working memory. That is, by using chunking, the working memory is able to handle more number of items at once.
Long-term memory includes both storage and retrieval, while Long-Term storage refers only to the location of the memories.
Information is most likely to be stored if it makes sense and has meaning.
In this context, sense refers to whether the learner can understand how the information fits with what s/he already knows.
Meaning refers to whether the information is relevant to the learner- why should s/he remember it?
Sense and meaning are independent of each other- one may remember something that makes sense, but has no meaning (is not relevant), and vice-versa.
When new learning makes sense, and can be connected to past experiences (meaning), there is dramatically improved retention.
However, of the two criteria, meaning is more important- something that is highly relevant is more likely to be retained than something that makes sense alone.
Past experiences always influence new learning. Therefore, if students make connections between subjects/ subject areas, and recognize a future use for the new learning, they will increase meaning and retention.
Long-term storage involves processing by the hippocampus, and usually occurs during deep sleep.
If a student cannot recall new learning after 24 hours, it is highly likely that it was not stored permanently, and hence, can never be recalled.
Note 1: Information that was not stored cannot be recalled.
Note 2: Typically, learners participate in activities that have yielded success for them, and avoid those that have produced failure.
Note 3: How a student feels about a learning situation determines the amount of attention devoted to it.
Note 4: Any sensory input that threatens survival, or is associated with emotions, takes priority over other data, and are processed immediately.
Items stored in short-term memory are lost after 20 minutes.
In order for information to be committed to long-term memory, it should make sense, and be relevant.
The process of creating long-term memories usually occurs during deep sleep.
Linking new learning to existing knowledge, and identifying a future use for it, dramatically increases both meaning and retention.
If one cannot recall an item after 24 hours, it was not committed to long-term memory.
Items that were not stored in memory cannot be recalled.
1. Sousa DA. How the Brain Learns: A Classroom Teacher’s Guide. 2nd ed. Thousand Oaks, California: Corwin Press, Inc.; 2001.