Another hypothesis - kids now are overstimulated, their brains are saturated with new stuff, but have not time to process it deeply. The deep processes are most

Another hypothesis - kids now are overstimulated, their brains are saturated with new stuff, but have not time to process it deeply. The deep processes are mostly activated when there is nothing new to register - i.e. mostly when the child is a bit bored. When there is new interesting stuff the brain is preoccupied by registering it and have no time for any deep reflection. This is not much different from our problems with too much food.