Reading Arabic 'hard for brain'(Link, BBC)
Article says the Arabic letters are too detailed (with the exact placement of dots and squiggles) compared to the relatively much easier Latin, Greek, Cyrillic, and Hebrew alphabets, whose letters are simpler and more clearly different from each other. The right brain gets confused.
Wonder how this compares to other scripts: Hindi, Japanese and so forth?
That was it. Thing is, if you are going to learn islam - in a madrassa or elsewhere - they also steep you in arabic, regardless of your actual language. And madrassas, even the ones in US islamic centers, like to get their students early. From around two and up. So the language training is being done to kids. Little seems to be known about these brain-half-disturbances being permanent or not, but I wouldn’t be surprised. Presto, a possible explanation of the muslim timeline-insanity.
And it is *only* arabic doing this. The other languages you mentioned (the closest being Hebrew) does not have enough irregularities to trigger the effect.