My guess is it's correlational. It's almost always correlational. Remember the knowing a second language reduced risks of dementia, turned out it was correlatio

My guess is it's correlational. It's almost always correlational. Remember the knowing a second language reduced risks of dementia, turned out it was correlational. The real cause was under diagnosis in immigrants who were disproportionately more likely to speak a second language. Still worth investigating further but dollars to donuts it's not causal.