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How Does Human Memory Work Mail to Me   

What is memory? Oxford Talking Dictionary explain the word as "the faculty by which things are remembered; the capacity for retaining, perpetuating, or reviving the thought of things past; an individual's faculty to remember things." This simply means memory is the knowledge which a person can recover or has recovered by mental effort; and the function of the mind is regarded as a store for this.

It would have been absolutely impossible for humankind to make any progress if we were not endowed with the faculty of memory without which we would have not been able to learn, retain the knowledge and pass it on to next generation.

Imagine yourself waking up each morning with tabula rasa - i.e. mind without any recorded impressions. How would you behave then? How would you make sense of the world around you? You are just as good as a newborn baby. And what kind of world it would be with billions of newborn babies of all ages. It's scary, isn't it?

However memory is so much of an integral system of brain processes that we seldom notice it being active. But whether we observe it or not brain is constantly registering details form our surroundings and storing it for future usage.
This happens largely in three parts. From an 'information processing perspective' there are three main stages in the formation and retrieval of memory:

  • Encoding or registration: at this stage brain is receiving, processing and combining received information so that it can be categorically stored.

  • Storage: at this stage brain is involved in creation of a permanent record of the encoded information.

  • Retrieval  or recall: this is when brain is calling back the stored information in response to some cue for use in a process or activity

A basic and generally accepted classification of memory stored like this is based on the duration of memory retention, and it identifies three distinct types of memory: 

  • headbrainx-large.jpgSensory memory:Â Sensory memory corresponds approximately to the initial 200 - 500 milliseconds after an item is perceived. Many of us must have participated in this exercise at schools where teacher would show us things randomly and then we are asked to reproduce their names. Well whatever we could remember within that short span is due to sensory memory. Scientists have preformed experiments on it which tells us that the capacity of sensory memory is approximately 12 items, but that it degrades very quickly (within a few hundred milliseconds). Sensory memory cannot be prolonged via rehearsal.
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  • Short term memory: Some of the information in sensory memory is then transferred to short-term memory. Short-term memory allows one to recall something from several seconds to as long as a minute without rehearsal. Its capacity is also very limited. Modern estimates of the capacity of short-term memory are lower, typically on the order of 4-5 items, and we know that memory capacity can be increased through a process called chunking.
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    For example, if presented with the string:

    FBIPHDTWAIBM

People are able to remember only a few items. However, if the same information is presented in the following way:

FBI PHD TWA IBM

People can remember a great deal more letters. This is because they are able to chunk the information into meaningful groups of letters.

Short-term memory is believed to rely mostly on an acoustic code for storing information, and to a lesser extent a visual code. People usually have more difficulty recalling collections of words that were acoustically similar (e.g. dog, hog, fog, bog, log).

  • Long term memory:Â The storage in sensory memory and short-term memory generally have a strictly limited capacity and duration, which means that information is available for a certain period of time, but is not retained indefinitely.

Image49.gifBy contrast, long-term memory can store much larger quantities of information for potentially unlimited duration (sometimes a whole life span). For example, given a random seven-digit number, we may remember it for only a few seconds before forgetting, suggesting it was stored in our short-term memory.

On the other hand, we can remember telephone numbers for many years through repetition; this information is said to be stored in long-term memory. While short-term memory encodes information acoustically (according to sound of the words), long-term memory encodes it semantically (according to meaning of the words). This means after duration of time we can easily remember words that are similar in meaning (e.g. big, large, great, huge).

Overview:
In psychology, memory is an organism's ability to store, retain, and subsequently retrieve information. Traditional studies of memory began in the realms of philosophy, including techniques of artificially enhancing the memory.

The best way to improve memory seems to be to increase the supply of oxygen to the brain, which may be accomplished with aerobic exercises; walking for three hours each week suffices, as does swimming or bicycle riding. One study found that eating frequently such as five small meals a day promotes a healthy memory by preventing dips in blood glucose, the primary energy source for the brain.
Other ways are..

  • to stay intellectually active through learning, training or reading, to keep physically active so to promote blood irrigation to the brain,
  • to socialize,
  • to reduce stress,
  • to keep sleep time regular,
  • to avoid depression or emotional instability and
  • to observe good nutrition.

The hippocampus is essential to the consolidation of information from short-term to long-term memory, although it does not seem to store information itself. Rather, it may be involved in changing neural connections for a period of three months or more after the initial learning.

One of the primary functions of sleep is improving consolidation of information, as it can be shown that memory depends on getting sufficient sleep between training and test, and that the hippocampus replays activity from the current day while sleeping.

So all the parents reading this; encourage your children to have enough sleep. Do not let them lose sleep during exam days. As we advise them never to skip meal we as should as well ask them not to abuse their body and mind and have enough sleep.

However all the student friends reading this; mind it not to make this information an excuse to nourish your laziness and oversleep. Remember there is no alternative to hard work and rehearsal and repetitive performance of a task also helps a great deal to boost your memory.

Editorial Team,
Mindfiesta

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