Selective Attention

One concept that I find interesting in the Lilienfeld textbook is selective attention. Selective attention gives us the ability to focus on one stimulus even when we are receiving many inputs from our surroundings. There are so many things happening around us in our everyday lives, it would be impossible to function if we could not "turn down the volume" of certain stimuli. This particular brain function occurs in the reticular activating system and the forebrain. This concept is important because it affects everyone on a daily basis. It affects our ability to have a conversation with someone while walking down the street, pay attention while driving, or respond to our name being called across a room. We tend to hear things that are important to us, such as our names. This phenomenon is called the filter theory of attention and the basic steps are shown in the image below.
One real life example of selective attention that is important in my life is rowing. In rowing there are many stimuli around each rower and the boat; the wind, the water, splashing, other boats, riverbank scenery, and the cold temperatures. However, the stimuli that are important to pay attention to are the rower in front of you, the voice of the coxswain, and your own muscle and body signals. Selective attention allows me to pay attention to what is necessary in order to perform to my best ability. Rowing takes a lot of focus so this concept is very important to my teammates and I. Without selective attention rowing and many other sports would not be possible.
I wonder if certain people have a better ability to ignore certain inputs because some people can do homework or read in a loud room, whereas others have to have complete silence. Also, some of my teammates are much better at focusing in the boat than others. I'm sure there is a reason for this but I don't know if it is related to selective attention or another function of the brain.