Concentration

There is a limited capacity for our brains to hold information in our immediate consciousness. If you were at a party, and you were introduced in quick succession to a number of people, you might be able to hold around 7 names in your mind. This is about as much as the average person can hold in the conscious memory (without applying specific memory techniques such as mnemonics). This ‘conscious’ capacity is essential to every task we do where we need to consciously interact with information. Most of what we do is not conscious. When you walk downstairs in your house you probably do not consciously think about putting one foot in front of the other on each step. You have walked up and down stairs, including your own stairs, so many times that it has become an unconscious action. But if I asked you to build me a spreadsheet in order to help me manage my finances, this task might involve a lot more conscious interaction on your part.

Norman and Shallice have called this ‘conscious’ capacity of the brain the SAS.The employment of the SAS is necessary every time we attempt a task that involves conscious application of our thoughts. Many tasks that we attempt to do involve some conscious interaction.

If we have to concentrate for long, (which involves utilising the SAS) the SAS gets tired. So for example, if you decided to sit down and learn some Spanish words, when you first sit down you might find you can concentrate quite well on this task. However, after a few minutes you may find that less information is being processed. After a little while longer, you may find that you can barely concentrate at all! Your SAS, which was being used to consciously process the new information being learnt, has become tired.