While there is still debate among attention scientists, most now conclude that there are three types of attention. The first is orienting — the flashlight of your mind. In the case of visual attention, it involves parts of the brain including the parietal lobe, a brain area related to sensory processing. To orient to new stimuli, two parts of the parietal lobe work with brain sections related to frontal eye fields. This is what develops in an infants' brain, allowing them to focus on something new in their environment.
The second type of attention spans the spectrum of response states, from sleepiness to complete alertness. The third type is executive attention: planning, judgment, resolving conflicting information. The heart of this is the anterior cingulate — an ancient, tiny part of the brain that is now at the heart of our higher-order skills. It's executive attention that lets us move us beyond our impulsive selves, to plan for the future and understand abstraction.
We are programmed to be interrupted. We get an adrenalin jolt when orienting to new stimuli: Our body actually rewards us for paying attention to the new. So in this very fast-paced world, it's easy and tempting to always react to the new thing. But when we live in a reactive way, we minimize our capacity to pursue goals.