You can think too much

People can think too much about their capabilities. Once you've mastered something, it's not a good idea to spend too much time thinking about it. Leiden cognitive psychologists Bruno Bocanegra and Bernhard Hommel have published an article on the subject in Psychological Science.

Sometimes less can be more

Bocanegra and Hommel discovered that in certain circumstances performance can deteriorate if you exercise too much cognitive control. This finding calls into question the traditional assumption that more information and more mental effort should lead to a faster and better result. But less can sometimes be more, in terms of cognitive control, particularly if the environment already offers enough information for the cognitive system to carry out the task on 'automatic pilot'. 

System of cognitive control can only handle one thing at a time

To give a few practical examples: when driving, you have no difficulty reacting to situations until you suddenly think about how to do a hill start, for example. You are then switching from automatic pilot to conscious activity, but that conscious system of cognitive control can only handle one thing at a time. Your extra mental effort disrupts your more than adequate automatic skills.  When you exercise cognitive mental control over something that you are already capable of doing, such as playing the piano or touch-typing, you break the chain of automatic actions. The automatic system is put on hold, as it were. Bocanegro comments, 'Cognitive control is effective until you have masterd something and your skills become automatic.'

Testing the hypothesis with computer tasks

The Leiden researchers developed computer tasks where a participant had to click the left or right button, depending on the stimulus given.  The participant was asked to make a mental effort to carry out a complex task.  A much simpler task cost the same participant a very limited mental effort. Without the participant knowing, the tasks were manipulated such that colour always predicted the right answer. According to the traditional hypothesis, the cognitive system automatically picks colour as predicting the right answer. Moreover, mental effort on the part of the participant should further strengthen the improvement.

Traditional hypotheseis falls short

The performances of the participants in the computer tasks indicate the opposite. More information for the participant should lead to the tasks being carried out faster and better. But this was not what Bocanegra and Hommel observed. Contrary to what you would intuitively expect, the predicting information of the colour had a negative effect on how the performance of the task. Even with extra information and more cognitive control, the participants did not perform any better. 

(28 April 2014)

Zie ook

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Last Modified: 06-05-2014