I'm thinking, please do not disturb.

Philosopher Arthur Schopenhauer, after middle age, moved to the bustling downtown area of Frankfurt with his beloved lion dog and began to experience the pain of urban noise. Around 1850, he declared that noise was the great enemy of any serious thinker. His argument was that a great mind could only achieve great thoughts when all its energy was fully focused on one point or one object; once distracted or interrupted, it would not be superior to that of an ordinary person. He also pointed out that even an average person, who might not be a philosopher, could lose rationality under the influence of noise.

In modern life, environmental noise and distractions are omnipresent. What effects do they have on our lives and cognitive activities? A paper published in 2009 studied the impact of airport noise on sleep, finding that even while asleep, the noise from planes taking off and landing caused sudden spikes in blood pressure, increased heart rate, vascular constriction, and the release of stress hormones among test subjects. These harmful cardiovascular reactions continued to affect individuals for hours after they woke up.