“For the most part, research has demonstrated that fear-arousing communications usually stimulate the audience to take action to reduce the threat. However, this general rule has one important exception: When the fear-producing message describes danger but the audience is not told of clear, specific, effective means of reducing the danger, they may deal with the fear by “blocking out” the message or denying that it applies to them. As a consequence, they may indeed be paralyzed into taking no action at all.”