You can often feel bored when taking a practice repeatedly. You may have a strong memory of spelling tests. Catch is one of the primary menus in baseball practice. Beginner Karate fighters have to mimic senior trainee's gesture again and again. Is it necessary to do such a simple task many times for the mastery?
The answer is yes, according to scientists. An experimental study suggests that "overlearning" has a preventive effect from forgetting the skill once you have acquired.
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Perhaps, there are some stages in your brain from the beginning to the mastery. The first stage is initial learning, or simply knowing the matter. You make a glance at the manual and recognize the manner of the skill. But this memory will vanish immediately because it is stored in the working memory. Through repeated practice, the instant memory is enhanced, to be changed into long-term memory. It means that you hardly forget the process of the skill. However, you may have difficulty to do the same thing in a different situation. The third stage is the generalization. You can utilize the manner you have acquired in another object, surrounding, and perspective.
And the final stage is overlearning. At this stage, the process of the skill is done at the unconsciousness level. Professional sports players often say, "My arms automatically catch the ball," or "I jumped up before I wanted to do so."
Once reached this stage, your skill never betrays you. Even if you are staying far from the field of the skill for a long time, you can remember the skill immediately when you need it.
Physician's skill is one of the examples. Elder physicians have many experiences of treating patients. Their observation and technique are overlearned to their body and mind. Therefore, they can behave as if a skillful doctor, even with dementia. Indeed, it is difficult to detect mild dementia among doctors.
Driving technique is also overlearned in many people. In Japan, traffic accidents caused by elder people is sometimes reported recently. But the percentage of the cases is far fewer than expected, considering the high prevalence rate of dementia in aged people.
In conclusion, overlearning is beneficial, at least in some kind of fundamental skills for you.