Is there validity to the assertion that left handed people's brain hemishperes are opposite to those of right handed people (meaning for a lefty the right side is the logical part and the left side is the visual side)?
If this is the case then when listening to paraliminal tapes should left handers reverse the way they wear headphones?

Nope, research has shown that over 67% of left handed people have same brain dominance as 97% of right handed people.

Less than 1/3 of the left handed folks actually showed a reversal.

When it comes to the paraliminal.. matters not.

You can experiement for the variety, however even if you lack hearing in one ear you will still benefit from the duel voices as they are actually both audible in both sides.

Alex