One of the “soft signs” for identifying autistics is the predilection for lining things up. Like anything else, this isn’t an exclusive activity, but rather something that is done in more pronounced frequency than the average population. Meaning, it’s not that neurotypical people don’t line things up, but rather, don’t do so with such intensity or such relish. What’s the big deal (the fascination) with lining things up, anyway? Why line things up?
There are a variety of inter-related reasons. For one, it makes it easier to find things without the “mental speedbumps” so I don’t get distracted and forget what I was doing in an ADHD moment. When pulling out four spice jars from the fifty others lined up on the pantry door racks I don’t even have to read the labels, just because the alphabetisation helps maintain the intrinsic order: cardamom is between caraway seed and cayenne pepper. This is good because quite a few of my (recycled) jars don’t even have labels.
Lining things up gives the hands something to do that isn’t mentally demanding, so the brain is free to relax and think about other stuff (some people describe knitting as being like that). This is like walking a labyrinth or meditating in its focused, relaxing qualities. Think of it as meditation for the ADHD person who can’t sit still!
Lining things up is not unlike ironing out wrinkles; the symmetry gets rid of the unevenness in the universe and gives one a happy, settled feeling. Objects seem relaxed and more likely to stay where they belong when they are comfortable – they won’t unfathomably “disappear” from where they were last left! All is right in the world because they are where they are supposed to be, like when jigsaw pieces are fitted together. There’s a happy “zip” feeling from running the fingers along the picket-fence effect of objects in a perfect row. Lining things up makes the world less of a jumble – there’s a visual appeal to the evenness.
It can also be fun to manipulate the patterns and constantly be creating new ones, this being a process-oriented task rather than a results-oriented task because it’s the doing that is pleasing, rather than the finished product.
When I had more room (in another house), I lined up cans and boxes in the pantry, creating neat files of canned fruits and different tomato sauces that made preparing grocery lists easier. I got particular satisfaction pegging diapers on the clothes line in neat arrays, and also hanging up the clothes to dry with all the shirts in rainbow order. I’m constantly fixing the alignment of the houses on the Monopoly board, or facing and centering the chess pieces. If I pause in front of a library bookshelf for more than a minute, I leave behind me a section of books lined up along the shelf edge. (No, it’s not quite at the level of Obsessive-Compulsive Disorder; I don’t do it to ward off Bad Things from happening, and it doesn’t create problems for me.) I keep my hangers sorted by style; crayons in rainbow order; reference books on shelves by category and novels by author; music CDs neatly lined up alphabetic within genre; positively relished organising my collections of stamps sorted by country, rocks by type, and insects by family; and tidy my wrapped tea bags or seed packets in neat horizontal stacks. I have been doing these things all my life, and in my mid-forties am not likely to change — there’s really no need to!
So, why not? What’s the big deal (the problem) with lining things up, anyway?
Andrea's Buzzing About: 
Sue said,
16 August 2008 at 1:53
I don’t have autism or aspergers, but I do have a personality disorder and I line things up when I am in stress. My more favorite thing to do is to go outside and line up rocks.
Centenary Retrospective « Andrea’s Buzzing About: said,
1 June 2007 at 23:07
[…] on developmental timetables, or they worry and wonder why their child likes to spend lots of time lining things up (it’s a good thing, […]
Autism Street » Next Year Is Right Around The Corner said,
15 December 2006 at 13:42
[…] On that note, don’t miss Andrea’s personal look at lining things up here, which includes the following: Lining things up is not unlike ironing out wrinkles; the symmetry gets rid of the unevenness in the universe and gives one a happy, settled feeling. Objects seem relaxed and more likely to stay where they belong when they are comfortable – they won’t unfathomably “disappear” from where they were last left! All is right in the world because they are where they are supposed to be, like when jigsaw pieces are fitted together. There’s a happy “zip” feeling from running the fingers along the picket-fence effect of objects in a perfect row. Lining things up makes the world less of a jumble – there’s a visual appeal to the evenness. […]
Bonnie Ventura said,
14 December 2006 at 14:16
Many years ago, my father had serious domestic problems with his second wife because she did not see the need to line up the groceries neatly in the pantry. She would put cans away upside down, and so forth. When he nagged her about it, she just told him to do the grocery shopping himself if it was such a big deal. Eventually they split up — an unfortunate case of incompatibility.
He gets along very well with Wife No. 3, though.