The brain’s level of arousal is a major factor in determining our capacity to give attention, as the neuroscientist Joseph LeDoux explains: Arousal is important in all mental functions. It contributes significantly to attention, perception, memory, emotion, and problem solving. Without arousal, we fail to notice what’s going on—we don’t attend to the details. But too much arousal is not good either. If you are over-aroused you become tense and anxious and unproductive. You need to have just the right level of activation to perform optimally.
