As far as I know, there have been exactly zero scientific studies of directional dyslexia. As a consequence, all of our knowledge is anecdotal. No one can say for certain whether the condition is inherited or acquired, or whether it's more (or less) common among women, southpaws, redheads, eastern Europeans, bad spellers, or chocoholics. "Common sense" suggests that it might be associated with right-left confusion, and indeed, a number of the individuals who've commented on ""People who Lose their Way" indicate that they have severe problems telling the one hand from the other. For example: one commentator reports that a lifelong problem is that "I've been completely unable to instinctively tell left from right." The emphasis on the word "instinctively" is meaningful. Without conscious effort, most unaffected people intuitively and easily understand the difference between right and left; for another class, some of them DDers, it's something that must be learned by effort, as in the case of the reader who thinks her DD is related to the fact that she "had lots of trouble as a child learning right and left," or of another who, learning to dance, can't consistently raise "right hand and left leg -- or vice versa." Another non-instinctive person "still doesn't know my left from my right (I have to put my hands out and see which one makes an 'L).'" A high school student plaintively confesses that her mom "threatened to write the words left and right on the back of my hands before I had to take the test for my driver's license." It's a frequent complaint: "I was almost 20 years old before I stopped having to think 'I write with my left hand... if I were to pick up a pencil which hand would I hold it in.'"
Is there, then, an association between right-left confusion and directional dyslexia?
I don't think that the evidence allows us to conclude so.
Most of the people who commented do not mention any such condition.
Perhaps they take it for granted that everyone in the DD community shares the trait -- but we don't. Even though I'm among the world's most frequently lost souls, I have not the slightest bit of trouble with left and right. In fact, I'd say that I'm hyperconscious of my handedness as well as the handedness of others. I always observe and remember which of my acquaintances are right or left-handed. And if someone says, "turn left," I turn left. Unerringly and instinctively.
Pending further investigation, the evidence suggests that left-right confusion is independent of directional dyslexia. It's a separate problem (and one which may further disorient those of us who are chronically lost).
Coming soon: east/west/north/south.