Strong Emotions May Cause Temporary Blindness 367
Iphtashu Fitz writes "Ever been watching tv when a violent image comes on the screen and you don't even notice that somebody just entered the room? You've just encountered something known as emotion-induced blindness. Psychologists at Vanderbilt and Yale Universities have determined that people can suffer short periods of blindness, up to 1/2 a second in length, immediately after seeing highly emotional images. By displaying a series of images for 1/10 of a second each they were able to determine that test subjects couldn't identify images shown immediately after very erotic or gory images. You can try this out for yourself at the flash-based test site they have set up which also contains more details of the experiments."
Not so sure about this... (Score:5, Informative)
I didn't see the target.
I replayed that thing about a dozen times before I finally caught it.
I suspect I missed it because "rotated 90 degrees" doesn't stand out enough to notice, with such complicated images and only a tenth of a second per image - Though I suppose using something like simple brightly colored shapes would tend to make the "graphic" image stand out unduly.
Anyway, once I finally spotted the target image in the last sequence, I nailed it first try in the first two sequences (the ones supposed to induce temporary blindness).
Then again, perhaps I just have a deep fear of fire hydrants, while bloody stumps don't really phase me.
Re:Maybe, but... (Score:5, Informative)
Image set 'B' was with the target image quickly after the hand.
Image set 'C' was with the target image in the same spot as 'B', but the hand was replaced with a fire hydrant.
C is clearly the control. Well, unless you have some sort of a hidden memory of something bad (or erotic) dealing with a fire hydrant.
Re:blindness during eye movement (Score:3, Informative)
for example... look towards a light source (preferably not directly) and look on different sides of it. then close your eyes (for best effect) and you will be able to see the movements of your eyes in relation to the light trails. explain this one... (i dont doubt you, i would just like to know why this is, when you strongly 'argue' 'against' it)
Because the retina is still gathering information; it's just not sending it to the brain. Basically, the retina is made up of a layer of light-sensitive cells, some that detect certain colors, others that detect intensity, etc. When they are exposed to a very bright light source, they tend to still register information to the brain, even after the light source is no longer there. These are called "afterimages [wikipedia.org]." In the case you are describing, the retina still gathered the light of the bright source, even though that information was not sent to the brain during the actual move. Once the move is completed, and you close your eyes, the brain starts interpreting the data from the retina again, and finds afterimages.
I hope that answered your question.
Re:blindness during eye movement (Score:3, Informative)
Yes, it's because it takes a small, but finite, amount of time for your brain to reset and reacquire its focus.
This also explains why pigeons, doves, chickens, etc. walk the way they do moving their head in fits and starts as they walk forward. The time lag for them to refocus their attention/eyes is pretty long.
It also explains another visual semi-trick or observation. People tend to blink more frequently when trying to absorb visual information faster than they usually do - each blink is like a camera taking a picture. Eye movement - flicking eyes from one area to another, works similarly, too. But when people get overwhelmed visually, their blink rate drops way off.
Re:Not so sure about this... (Score:3, Informative)
The target picture was a sideways lighthouse.
And yes, I didn't notice the lighthouse either, even on the "control" sequence. I thought it was the tree branch with the mountain.
I agree with the parent that all this shows is it's hard to notice a side-ways image that's white with low contrast when it's only shown for 1/10th of a second.
Re:I've seen it happen (Score:2, Informative)
http://www.nimh.nih.gov/publicat/reliving.cfm [nih.gov]:
"Post-traumatic stress disorder (PTSD) is an anxiety disorder that can develop after exposure to a terrifying event or ordeal in which grave physical harm occurred or was threatened. [...] Many people with PTSD repeatedly re-experience the ordeal in the form of flashback episodes, memories, nightmares, or frightening thoughts, especially when they are exposed to events or objects reminiscent of the trauma. [...] Physical symptoms [...] are common in people with PTSD."
http://survive.org.uk/PTSD.html [survive.org.uk]
"Inability to recall important aspects of the trauma, is another of the ways avoidance and numbing may work. This means the person cannot remember exactly what happened. Many trauma survivors forget in order to survive. Survivors may also have learned to dissociate, to literally not be there, to survive. They automatically "switch off" during a stressful situation because it is too painful to deal with."
The above quotes suggest that the temporarily blinded man might have either voluntarily or involuntarily chose "not to see" horrors during the incident. It's possible that re-living the experience caused the "not to see" command to reactivate.
Another possible explanation is that the body dumps an incredible number of chemicals into the bloodstream during these situations, and again when the person re-lives them. These hormones profoundly effect the way the mind works.
I hope this man and the others find a way to cope with their terrible experiences.
Coca-Cola is evil. (Score:3, Informative)
Reminds me of a flurry of adverts which made the rounds a couple of years back; where highly stressful social situations were depicted, (a family arguing over their teen daughter's announced pregnancy, a couple in a strained relationship having an argument, etc.), followed immediately by a product placement. Icky and not very cleverly disguised, but then most of the audience didn't understand what was being attempted.
The moral of the story: Never trust a Coca-Cola product or company. --Any corporation willing to play creepy mind games to sell their product should be denied existence.
-FL