Doing more than one thing at a time divides attention and fragments consciousness. When we read and eat at the same time, for example, part of our mind is on what we are reading and part on what we are eating; we are not getting the most from either activity. Similarly, when talking with someone, give him or her your full attention. These are little things, but all together they help to unify consciousness and deepen concentration.
Everything we do should be worthy of our full attention. When the mind is one-pointed it will be secure, free from tension, and capable of the concentration that is the mark of genius in any field.
— Eknath Easwaran, Your Life Is Your Message