Jon Krakauer said this quote

“ Boredom presents a very real, if insidious peril. To quote Blaine Harden from the Washington post:“Boredom kills, and those it does not kill, it cripples, and those it does not cripple, it bleeds like a leech, leaving its victims pale, insipid, and brooding. Examples abound...Rats kept in comfortable isolation quickly become jumpy, irritable, and aggressive. Their bodies twitch, their tails grow scaly. The backcountry traveler, then, in addition to developing such skills as the use of a map and compass, or the prevention and treatment of blisters, must prepare mentally and materially to cope with boredom, lest his tail grow scaly. ”