CONSUMERS' MENTAL FILING CABINETS
Ads are like alcohol: the more you have the less you remember. After only two or three drinks your faculties start to become impaired. After exposure to only one or two competing ads, your memory for the first one starts to become impaired.1 What is true of alcohol is surprisingly true of consumer memory for advertising—at least for competing brands in the same product category.
Over a period of a week, the more competing commercials there are for a product category, the less the average person will remember about any one of them. Most people think that forgetting is simply the fading of memory with the passage of time. However, it is now well established that forgetting is due not to the passage of time alone, but to interference from additional learning that takes place in that time.2 When time passes but little or no further (competing) learning takes place there is very little forgetting.
On the other hand, where a lot of activity and new learning, especially competitive learning, fill the time interval, these 'interference effects' become very great indeed. These effects are one of the clearest of findings on the way human memory works.3 They are also one of the most frequent findings to emerge from continuous tracking of advertising.
Some will argue this only applies to explicit memory and does not apply to learning without attention because there is evidence that implicit memory (see Chapter 27, 'Measurement of advertising effects in memory') is much more durable. The argument is a false one, however, because it confuses learning in the absence of awareness, i.e. implicit learning, with implicit memory. They are not the same thing. Do you touch type? If so, then the location of the keys is stored in your implicit memory.