When most marketers think of copy, graphics, etc, they tend to think of shapes and colors first and sounds second.
And nothing else.
This isn't unreasonable. Graphics are an exclusively visual interface. Direct Mail and Direct Response are read-only. Video format ads are seen and heard. Lastly, radio and podcast ads are purely auditory.
The bottom line? You seldom get an opportunity to feel, smell, or taste an ad campaign, Pepsi Challenge notwithstanding. But this doesn't mean you should ignore the other senses. I'm not suggesting some scratch and sniff Direct Mail, or textured billboards, or lick-able brochures.
Instead, think of what senses are internally triggered by the appropriate language and imagery. Seeing steam rise in gentle, translucent curls above a mug of black coffee doesn't just provide an image. The aroma of coffee, and all the emotional cues that go with it, are activated. Hearing the sizzling of steaks on a radio commercial sparks the same response but with flavor. Seeing someone nuzzle a soft pillowcase with the words "750 thread count" invokes the same sensation with regard to touch/tactile sensation.
The lesson in all this? Sure, marketing may be limited to eyes and ears most of the time, but that doesn't mean you can't appeal to the other senses to great effect by thinking of how those responses work and in relation to certain words, sounds, and images. Appeal to all the senses even when you're just using two, an you've more than doubled your marketing palette.