I had two pieces of gluten free banana bread this morning for breakfast. My wife makes it now and then. This morning I noticed, again, that I don't like the round bite marks left in the previously rectangular bread and feel compelled to bite the tips off so that the bread is returned to its roughly rectangular shape.
I'm the same way with a sandwich (don't get many of them these days) or any square food item. The bite mark seems chaotic and disorderly.
I can only guess that there is a part of the brain that identifies the general shape and properties of a piece of bread as being rectangular or square and another part of the brain that assigns meaning to the bite mark. There are probably still other sections that develop texture, color, etc. All these elements a some how combined by another part of the brain and then forwarded to the frontal lobe so that it can decide what I think "about" it.
In a neurotypical brain, a bite mark in food would usually mean nothing unless you hadn't started eating your food yet. Then it would be a problem, especially if the waiter just set it down in front of you supposedly fresh from the kitchen. Then the executive function of your brain would raise an alarm that some one else had taken a bite out of your food, and would set off a cascade of other reactions.
So, I think it goes back to the whole sensory integration. I'm guessing that because those of us in the Autism spectrum have a deficit when it comes to integration, that the something isn't getting combined and forwarded correctly to the decision making part of the brain. So, while that bite mark isn't alarming, it is vaguely disquieting. I even out the edges and it feels right again ( of course then I feel just a little neurotic).
Perhaps the message that the bite mark belongs to me is lost in processing. I have a memory of biting the bread and eating it, yet the perhaps the visual image of the bite mark has not been integrated with the other sensory and cognitive memories of biting and eating. So, I know it's my bite mark, but there is a missing "green flag" and it makes me feel a bit uneasy.
Just some guessing based on what little I've read about brain function.