Porn makes you blind: official
Temporarily, thank God
A Vanderbilt University research squad has illustrated what the Victorians and Mary Whitehouse knew all along: that smut sends you blind, albeit temporarily. The same apparently applies to blood and guts images, although of course eyeballing snaps of carnage does not carry the same penalty of eternal damnation as ogling smut.
Vanderbilt Uni psychologist David Zald and his team exposed guinea pigs to a barrage of "disturbing" images interspersed with landscape or architectural snaps, telling them to scan the images for a certain target image. The press release explains: "An irrelevant, emotionally negative or neutral picture preceded the target by two to eight items. The closer the negative pictures were to the target image, the more frequently the subject failed to spot the target. In a subsequent study, which has not yet been published, the researchers substituted erotic for negative images and found the same basic effect."
The bottom line is, says Zald: "We observed that people fail to detect visual images that appeared one-fifth of a second after emotional images, whereas they can detect those images with little problem after neutral images."
So, what's it all about? Well, the boffins reckon it's related to the "rubbernecking" concept - the process whereby you try and drive by an accident without having a shufti but "our emotions of concern, fear and curiosity cause us to stare out the window at the accident and slow to a crawl as we drive by".
We suppose that the same process is at work when you attempt to motor past an attractive member of the opposite/same sex (according to taste) and not cop an eyeful, fail dismally and pile into the back of the police car sitting at a zebra crossing.
Or that's what we think they're talking about, ie, a strong visual or emotional stimulus temporarily disables your faculties. The Vanderbilt blurb notes that previous studies have demonstrated "there are limits to how much information we can hold in our visual short-term memory and that we often miss visual images that pass right before our eyes if we are paying attention to something else".
Zald explains: "We think that there is essentially a bottleneck for information processing and if a certain type of stimulus captures attention, it can basically jam up that bottleneck so subsequent information can't get through. It appears to happen involuntarily."
And there's more: an individual's ability to control his or her attention was "directly linked to the aspect of their personalities that involves their reaction to negative or frightening stimuli, assessed by using a scale that measured their levels of harm avoidance".*
In other words, "fearful or cautious" people have more trouble disengaging from emotional images, while those with a higher devil-may-care quotient "are more often carefree and more comfortable in dangerous or difficult situations".
Presumably, then, only those with a healthy disregard for danger should attempt to drive past a particularly nasty multiple pile-up while flicking though a copy of Playboy. As for the rest of us, it's eyes firmly fixed forward and Miss October back on the top shelf where she belongs. ®
*For the record, here's how the Vanderbilt team probed their subjects for "harm avoidance" or otherwise. There's more information available at the dedicated Vanderbilt website.
In the second experiment, the researchers sought to determine if individuals can override their emotion-induced blindness by focusing more deliberately on the target for which they are searching. In this experiment, the subjects undertook two different trials. In one they were told specifically to look for a rotated photo of a building; in the other they were told to look for a rotated photo of either a building or a landscape.
The research team hypothesized that the more specific instruction - to look for the building only - would help the research subjects override their emotion-induced blindness. After running the tests, the researchers discovered that they were partially right: specific instructions helped some subjects control their attention, but it didn't help others.