Law of primacy in persuasion
In persuasive communication, the order of the information's presentation influences opinion formation. The law of primacy in persuasion, otherwise known as a primacy effect, as postulated by Frederick Hansen Lund in 1925 holds that the side of an issue presented first will have greater effectiveness in persuasion than the side presented subsequently. Lund presented college students with a document in support of one side of a controversial issue and then presented a second document which supported the opposite position. He found the document read first had greater influence, regardless of which position it expressed. This empirical evidence was generally accepted until 1950, when Cromwell published findings of the opposite: a recency effect in which arguments presented later had greater effectiveness in persuasion than arguments presented first. It now appears that both primacy and recency effects occur in persuasion. Theoretical background There are many different theoretical models proposed to explain the occurrence of primacy and recency effects. Sensory-variation Schultz (1963) developed the "sensory-variation" hypothesis for order effects, which suggests that humans seek high activation and will respond to novel stimuli more strongly than to stimuli they are familiar with. Novel stimuli should provide higher activation than familiar information, according to this