Processing Invisible Images

by F.

LiveScience has a story on unconscious processing of images. The take away:

Past studies have shown that the brain can process invisible information, but the new study shows it doesn’t simply register the information, but also processes it in specific ways. A subliminal stimulus can attract or repel attention and thus influence our actions in different ways.

The study:

In an experiment, 40 men and women were shown erotic images that had been manipulated to bypass conscious detection. The participants consisted of both heterosexual and homosexual individuals.

Subjects were then shown a small “probe” pattern and asked to determine its orientation—clockwise or counterclockwise. The researchers found that subjects identified the probe pattern more accurately when it appeared where the erotic images had been, suggesting that the invisible images exerted an effect on their spatial attentions.

In general, the erotic images attracted or repelled attention depending on the gender of the nude model and also the sexual orientation of the subject. For example, heterosexual males tended to perform better on the pattern task when it followed the presentation of an invisible female nude than a male nude. Gay males, in contrast, showed more enhanced performance when exposed to invisible male nudes compared to female nudes….

While I haven’t seen a reproduction of the pictures the researchers used, I believe they look like those “Magic Eye” pictures. Like noise, essentially:

The researchers took advantage of a phenomenon called binocular rivalry to make the erotic images invisible. When two very different images are presented to each eye separately, the images will alternate between one image and the other. But if one eye is exposed to an image and the other to dynamic visual “noise,” the noise will suppress the image and render it essentially invisible to the viewer.