Heart rate, respiration rate, blink rate and electromyographic activity of lateral frontalis were assessed in response to passive zapping which is defined as a frequent shift of attentional focus induced by external events. In particular, for this study, passive zapping consisted of frequent shift of TV sequences (this phenomenon is present during commercials, videoclips and during normal TV programs in order to catch the attention of spectators). The shift rates were of 6 and 12 shifts per minute. Subjects were 36 university students (12 males and 24 females). Results demonstrated that high shift rates (greater than 6 shifts per minute) cause an increase in heart rate and respiration rate (augmented arousal) and a reduction in blink rate (increase in attention devoted to TV sequences). No differences were found in electromyographic activity.