vender. we did this poll and asked if that's a model for the whole country. 33% yes. 37% say let's wait and see how it plays out. what do you think? first of all, let's look at the age. 21 and older, you specifically look at the impact on brain development. what do you make of that age of 21 being the cut off? >> during development, lots of things happen to the brain. it's unfortunate that we don't have a definitive time at which we know the brain is finished developing and it's clear you can go whatever you'd like. while the brain is developing the frontal cortex is the last to come online. the most important for things like regulating pulsivety, we already know that lots of emerging adults have difficulties making good decisions for not being impulsive. if you add to that different types of drugs or alcohol, it's going to be more difficult to behave appropriately. and what we have seen is some