
This article from the BBC say that it is. Due to the fact that many Arabic letters are very similar, mainly the ones that only differ in the number of dots they have, the left side of the brain is the only side that works when reading Arabic. This is in contrast to languages like English and Hebrew where most of the letters are very different from each other. I remember confusing "b" and "d" as a child though and I've seen some people who are learning English do the same since the two letters are just a mirror image of each other. When I was learning the Arabic alphabet about 3 years ago I always mixed up the letters, and one can see how that is easy to do. You've got ن ت and ث which only vary in number of dots, ح ج and ح as well as ص and ض and don't forget ع and غ. Pretty much every letter can be changed into another letter by adding or taking away a dot and I guess the right side of the brain has trouble dealing with that. I wonder what the brain does when you're trying to decipher Arabic calligraphy. :)