AT 4 O’CLOCK each morning, Laura J. Sloate begins her daily reading. She calls a phone service that reads newspapers aloud in a synthetic voice, and she listens to The Wall Street Journal at 300 words a minute, which is nearly twice the average pace of speech. Later, an assistant reads The Financial Times to her while she uses her computer’s text-to-speech system to play The Economist aloud. She devotes one ear to the paper and the other to the magazine.