Why We Forget
1.Negative self-concept: we think of ourselves forgetting things.

2.We have not learned the material well.
If something is to be retained, it must be correctly, clearly and forcibly impressed on the mind.
We must give it the necessary attention and interest. Self-questioning and spaced or periodic reviews are essential.

3.Psychological reasons: defensive forgetting
Generally, unpleasant things are remembered better than pleasant things (especially by pessimists) and both pleasant and unpleasant things are remembered better than materials we are indifferent to.
Freudian theory holds that unpleasant things are often barred from consciousness. This is often referred to as active forgetting.

4. Disuse
Memories fade away rapidly when not reviewed or used. The curve of forgetting is like a playground slide; we forget most immediately after we learn -in the first 24 hours; then it proceeds slowly. Motor learning seems to be better retained than verbal learning because a motor act has to be completely done to be done at all and so requires a higher degree of organization and competency which involves over-learning.
But "forgotten" material can be relearned in less time than is required for the original learning, even after many years' disuse. EVEN MATERIAL THAT WE DO NOT RELEARN HAS UNDOUBTEDLY BEEN TRANSFORMED INTO ATTITUDES AND VALUES THAT FORM THE FOUNDATIONS OF OUR JUDGMENT. EDUCATION PAYS IN SPITE OF ALL THE DETAILS THAT ARE FORGOTTEN.

Forgetting through disuse is normal and unavoidable. The mind is a marvelous instrument, but not a perfect instrument.

Eman Abdulmohsen, peace be upon you
Honey, I'm pleased to read your post here. Motor learning is the opposite of verbal learning. Consider this example:
You hold ten papers and memorize them orally, then this learning is VERBAL.
You try to illustrate the data you read on these papers using diagrams, pictures, etc. or even just you try to rewrite them on your hand in certain order, so this learning is MOTOR.

Motor learning is also related to the information the brain gets in association with certain activities, movements, sounds,etc. consider the famous experiment of the Russian psychologist, I think his name is Pafflo?, “ the dog and the bell”. In this experiment he noticed that the dog’ saliva was increasing when it heard the bell of its master calling it to have its meal. When the psychologist closed the dog’ eyes and rang the bell, the dog produced also much saliva though there was no meal actually in front of it.

Here we are!
Where are the readers? Everything is ok? I hope so. At the same time,I hope we discuss the information furnished here. That’s why I’ve posted this topic here.

It's the last part of "why we forget"; if you are interested I'll go on mentioning afterthat " Memory Improvement".

5.Interference
Forgetting was formerly thought to be mainly the result of disuse, but now it is believed that disuse may be a less important factor than interference due to emotional problems, anxieties, distractions, intense concentration on something else, and intellectual interference.
Intellectual interference or mental overcrowding can be minimized if we reflect on our reading and experiences, understand them, clarify them, associate, synthesize and organize them so they will not interfere with each other. Above all, we must avoid pushing, cramming and overcrowding our learning hours with unorganized material.

Forgetting caused by later learning is called retroactive inhibition. There is more interference between two similar subjects than between two unlike subjects. (Follow study of history with chemistry rather than English history or literature.
Since we cannot be awake without thinking, it should follow that there is more loss of memory for learned material when one is awake than when one is sleeping. (Study and then sleep.) Next to sleep, nonintellectual activities like exercise, music, dancing, recreation and the like cause the east interference with remembering what has just been learned.

When previous learning interferes with subsequent learning, this is called proactive inhibition. (An old poem interferes with a new poem-the more familiar the subject, the more interference.

Life, it seems, should be more organized, certainly our mental life, and should be approached with a degree of deliberation. There should be rest periods at intervals to allow the brain to lie fallow. Continuous undifferentiated activities apparently fight for a place in the memory; some things are pushed out and forgotten. FOR EXAMPLE, YOU WILL LOSE MOST OF THE KNOWLEDGE IF YOU QUICKLY READ BOOK AFTER BOOK WITHOUT ORGANIZING THE INFORMATION, REFLECTING ON IT, AND CLARIFYING IT.

Blocking is another kind of interference. It occurs when one wishes to recall some quite well-known information but cannot do so, such as names. Relax and try association.

6.Changed Cues
You may have all the information you need stored away in your mind somewhere but be unable to get at it if the right cue is missing. Recall what happens on tests. You studied the material one way, the test question was presented in another (cues were changed). If you learn material with too great dependence upon the phraseology of the textbook, you may be at a loss to remember some of the material if you cannot recall the exact wording of the text. As with your outlining assignments, restate or rephrase the ideas in your own words to insure remembering.

7.Lack of Attention and Effort
The art of memory is the art of attention-attending to the material WHOLLY. Moreover, there must be effort to remember.
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