Concentration has been defined as "the ability to direct one's thinking in whatever direction one would intend".
Knowing how to do something gives confidence that our efforts will be successful, so we don't have to deal with anxiety about will this work or not. It is much more difficult to concentrate if our surroundings keep intruding on our awareness, perhaps because it is noisy, too hot or too cold, the furniture is uncomfortable or the people around us are stressing out.
People sometimes refer to a concentration span : this is the time we can concentrate on a specific task before our thoughts wander.
Focus on the personal rewards of completing the topic satisfactorily (even if its only to be rid of the task) and build in treats to reward yourself as you progress through the task. If you are not quite sure what you are supposed to be doing or why you are doing it then it will be difficult to maintain concentration. But at other times our thoughts are scattered, and our minds race from one thing to another. In learning concentration skills, we aim to extend our concentration span - bearing in mind that we will have a different span for different tasks. It could be described as a sort of tunnel-vision, or as being focused: you keep your concentration on what is in front of you.

They only have a short-term effect of making you feel alert, and too much or too long an exposure can have serious effects on your physical and mental health. Use mind-maps or spider diagrams to record the search, and write test questions to summarise your learning after each study session. You could try to define the task in terms of its content and purpose, and then to make a realistic estimate of how much time and effort will be required to do it. To deal with such times, we need to learn and practice concentration skills and strategies. This in turn raises self-esteem, which makes us more able to concentrate, if only because we don't have to worry about how awful we are or life is. The following three skills are basic to concentration: if you want to improve your concentration, start by practising them. Once you know your learning style, organise the material to suit it: if you don't, learning will be more of a struggle than it need be and your concentration will suffer.
To expand your concentration span, just try to keep focused for a little longer each time by using STOP! If you dream of sitting out in the sun when you are in a library trying to study, make your reward a period of sun-worship (with the appropriate sun-screen cream).

Ask yourself how you will use the material, where it fits into what you already know, what new questions it triggers. To concentrate, we have to learn a skill, and as with any skill this means practice repeated day after day until we achieve enough improvement to feel that we can concentrate when we need to.
Whenever an anxiety or distracting thought enters your mind during the day, banish it until your next worry time, and re-focus on to what you are supposed to be doing.
If you don't know how you learn best, try to analyse your experience either with someone who knows how you work, or with someone with expertise in this area. Practice with something that doesn't matter in terms of the task: you could expand your lecture concentration span by practising listening to the news on the radio.
Then treat them as individual tasks, summoning up your concentration for each of them separately.
Don't waste energy trying to keep thoughts out of your mind (forbidden thoughts attract like a magnet!), just put the effort into STOP and re-focus.

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