It weighs like half a bag of flour and has more holes than a sponge, but if we look closely, we find that the brain is also a complex and vibrant part of our body, one that undergoes physical changes as we learn. Join neuroscience for a brief sojourn into the realm of memory ? a world of neurons and synapses, the agents of our learning, which with a ?do or die? approach demand care and stimulation. Use of gum is recommended during in-flight ? not to prevent earaches, but to promote learning.