When exposed to a stimulus, consumers may respond in entirely different ways due to individual perceptual processes. A number of processes potentially support or interfere with perception. "Selective exposure" occurs when consumers decide whether to be exposed to information inputs. "Selective attention" occurs when consumers focus on some messages to the exclusion of others. "Selective comprehension" is where the consumer interprets information in a manner that is consistent with their own beliefs. "Selective retention" occurs when consumers remember some information while rapidly forgetting other information. Collectively the processes of selective exposure, attention, comprehension and retention lead individual consumers to favor certain messages over others. The way that consumers combine information inputs to arrive at a purchase decision is known as "integration".