From LifeHacker

http://lifehacker.com/how-clutter-affects-your-brain-and-what-you-can-do-abo-662647035

"Whether it be your closet or office desk, excess things in your surroundings can have a negative impact on your ability to focus and process information. ThatâÂÂs exactly what neuroscientists at Princeton University found when they looked at peopleâÂÂs task performance in an organized versus disorganized environment. The results of the study showed that physical clutter in your surroundings competes for your attention, resulting in decreased performance and increased stress."