“Variation in the stimulus offered to students . . . can gain attention. When teachers (like actors) vary their volume, pitch or rate of speech, they are varying the stimulus in ways likely to arouse the orienting response. When teachers write on the board in

different colors
or place
words in
unusual
patterns

they are more likely to elicit attention; that is, more of the information they want to be attended to ends up in working memory. Emotional stimuli also can capture attention. For example, words like “blood” or “gold” or our own name are likely to elicit an orienting response. Vivid similes and metaphors have the same attention-grabbing properties. Who would not attend further after hearing, “My love is like a red, red rose” or ‘He was known in the field as Doctor Death.’”

—N.L. Gage and David C. Berliner, from Educational Psychology, fifth edition, 1992.