Why do You Turn Down the Radio When You’re Lost? You’re driving through suburbia one evening looking for the street where you’re supposed to have dinner at a friend’s new house. You slow down to a crawl, turn down the radio, stop talking, and stare at every sign. Why is that? Neither the radio nor talking affects your vision.Your attentional capacity can be taken up by inhibiting (tuning out) distractions, dividing your attention across multiple things, or even sustaining your attention on one thing (vigilance). Fatigue takes a big toll on attention. If you’re tired, it’s harder to concentrate. Depression has a similar effect. In fact, many memory complaints may be actually depression or fatigue-related reduced attentional capacity.