Stare at a lightbulb for a few seconds, and when you look away you’ll see a colored spot no matter where you look. That’s an “afterimage,” and these ghostly remains of what you are looking at can be much more interesting than a mere bright spot. Here’s a demonstration of a color afterimage:
In that illusion, the black-and-white picture appears in color for a few seconds due to the afterimage from looking at the initial reverse-color screen. (If you thought the color was in the video, go back and look at it again!)
Here’s another interesting illusion created by an afterimage:
So, given that creating an afterimage is an interesting way to trick our brain into seeing something that isn’t there, why haven’t marketers exploited this in some way? Part of the issue is that it’s not so easy to create the image. Few consumers will want to stare at a meaningless image or a blue dot for a long time in order to see some kind of commercial message. (I do think if the branding image was amusing enough when revealed some people might make the effort to view it.)
Building an afterimage doesn’t have to take that long, though, if the light is bright enough. Old-fashioned flash bulbs, for example, created powerful (and annoying) afterimages because of their combination of intensity and duration (long when compared to a typical strobe). So, using a bright light source will avoid the need to have people stare fixedly at an image. Recognizing this, BMW (a name linked with neuromarketing efforts in the past) created this example of afterimage branding using a flash projection technique:
Some people consider this “subliminal,” though since the viewer eventually sees the “BMW” the ad doesn’t really bypass conscious perception.