I've always wondered why ads in adult publications don't feature naked people since contextually that would seem appropriate. Reading such a magazine, at least in part, is a goal-oriented activity -- you buy a Playboy to look at nudie pics and skip whatever content doesn't have them. If you ad features the desired content, it gets looked at. Kind of makes sense, no?
To see how it would work, check out this placement of Volkswagen Tuareg in a photoshoot for a Ukranian edition of Playboy (warning: naked people ahead, not safe for most work places).
On the other hand, "Sexual imagery attracts a viewer's attention and processing resources, leaving few resources available for processing of other ad information. As a result, brand information (i.e., reasons for buying the brand, brand name, sponsorship) is not processed to the same degree." (source)
Sexual imagery leaves few resources for processing other information.
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