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."
Situational awareness (Score:5, Interesting)
The failure to attend to or notice changes in your environment due to more traffic in cortical associative areas is not surprising really, and has long been known by cognitive scientists working with Air Force pilots. The more tasks required or stress induced upon a situation will degrade attentive performance and result in missing changes introduced into the environment.
For all you gamers out there, this is sort of an intuitive concept, right? How many times have you missed the doorbell, telephone or significant other trying to get ahold of you in the middle of a Doom/Marathon/Unreal fragfest? You increase the number of participants (and thus tasks to attend to) and you decrease your situational awareness of your immediate surroundings.
Hmmm (Score:2, Interesting)
"seeing red" (Score:3, Interesting)
I guess with age I've mellowed, as I haven't been as mad as that since losing the contest for the Slashdot Cruiser -- well, maybe since the Karma Cap was instituted... or was the last time when I saw my first Microsoft ad on Slashdot? Hmmm...
Conflicting crime scene testimonies (Score:4, Interesting)
Might such periods of "blindness" be in part responsible for the inability of crime witnesses to recall details, and, for conflicting crime reports by witnesses.
There is the classic gambit of a law professor having a mock murder take place in front of law students to test their ability to recall details correctly. OTOH there was Aldus Huxley who, when left alone at home, would answer the door, deal with whomever was at the door, and, then return to his work without any memory of having dealt with some mundane task. A. Huxley was also able to recall, verbatim, pages of his college texts after having been given only a slight prompt.
Charles Tart in his book Altered States [amazon.com] gives a fun run down on some of the oddities of human consciousness.
Very timely write-up (Score:5, Interesting)
blindness during eye movement (Score:5, Interesting)
The coolest experiment used an eye tracker that painted words on the screen only where the fovea (the high resolution central portion of the retina) was looking and painted "X"s on the screen everywhere else (the low resolution bulk of the eye). Every time the subject's eye moved, the screen was redrawn to show the words where they were now looking and hide the words were they weren't looking. Subjects could read documents normally and were totally unaware that the screen was, in reality, full of "x"s except where their central field of vision happened to be pointing.
The point is that the eye & brain is not a simple pixel-based camera.
Re:Not so sure about this... (Score:2, Interesting)
That said, I don't think they've been exhaustive enough to support the conclusion. Sure, they've proven that people are less likely to recognize a distinctive image shortly after another distinctive image. I RTFA, and I don't see any mention of testing where, instead of violent or erotic images, they used checkerboard patterns or other emotion-neutral pictures that nonetheless stand out from the rest in the set.
I still think it's interesting and useful research, but I don't think they've really controlled for enough variables to support all of their claims.
Re:This explains some "eyewitness" problems (Score:4, Interesting)
Re:Blindness (Score:5, Interesting)
The classic demonstration of low level versus high level functionality has to do with something called a "true cortical blindness". In these cases, trauma or stroke (whatever) that damages occipital cortex may in some rare cases render a person functionally blind. However, when you throw a ball at them, strangely, they are able to catch it. Obviously there is some visual function related to vision taking place. What is happening here is that the tectum or visual centers in the brainstem whose functionality is orienting to place and timing are perfectly intact. However, visual centers related to conscious perception of what is being seen are damaged. All other visual pathways are intact.
I've seen it happen (Score:5, Interesting)
My brothers and I operate a chain of grocery stores in Jamaica. Two months ago, one of the small stores was invaded by four gunmen who made the staff lie on the floor, shooting three of our employees in the process; fortunately their wounds were minor. While they attempted to open the safe in the manager's office, she surreptitiously placed a cell call to the police station, which is only about 100 meters away. When the police arrived, a 45-minute shootout ensued, during which the police shot and killed two of the assailants. The police eventually teargassed the building, and when the remaining two attempted to slip out by mingling with the staff as they left, they were attacked by a large, very angry, machete-carrying mob that had gathered on the scene, and hacked into mincemeat. I really have no sympathy for the bastards, but Jesus, they died horrible, horrible deaths. When I eventually reached the store after visiting the staff at the hospital, the police were still hosing away blood and fragments of flesh.
After seeing the three injured employees being treated, I arranged for the others, who were badly traumatized, to have a counseling session, and it was heartbreaking to hear them describe the ordeal of lying on the floor for 45 minutes while a firefight raged around them. The were showered with broken glass, lying in blood, having to look at the bodies of the two dead gunmen, one of whom had had his face shot away. They didn't believe that they were going to survive. While one of the group was recounting the events to the psychologist, he started sweating profusely, I mean veritable rivers running off his face and arms, and complained suddenly that he couldn't see. He didn't respond to hands being waved in front of his face, and the psychologist assured him that he'd seen this happen before as a result of extreme stress, and that his vision would return in a few minutes. I honestly don't know if he was just spinning a line of bullshit to calm down the guy, but sure enough, his vision returned in about five minutes. Clearly he hadn't suffered any physical injury apart from some cuts and bruises, but I can only surmise that the extreme psychological stress had screwed with his brain somehow. Can anyone shed any light as to the mechanism that could have caused this?
Re:I've seen it happen (Score:1, Interesting)
I'd go further into abnormal psych... (Score:3, Interesting)
It would seem to point to a quality of selective attention, that when we attend to internal echoing imagery we are blind to our external senses, and we may get lost in dreams for long periods... days or months.
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Re:This explains some "eyewitness" problems (Score:3, Interesting)
I do remember waiting for the impact, though, almost like it was slow motion. I was driving into an intersection, had the green light, and this guy ran the red light right into my driver side door going around 70-80 mph. This is in a 30 mph zone. After the impact with me, he went through a fence, over a lawn and up a hill, caught a bit of air and landed on the edge of their garage roof, then fell down on top of a car parked in their driveway (the driveway is cut into the hill.) He managed to wreck 3 vehicles, my car which was only 3 months old, his own, and the car he landed on. He was seriously injured, but did recover.
Re:I've seen it happen (Score:1, Interesting)
Re:I've seen it happen (Score:2, Interesting)
IANAP (I am not a Psychologist), but if I had to guess, I'd say that it was similar to how when a body experiences an extreme amount of physical pain they go into shock. In this case, the brain goes into shock and shuts things off
Re:blindness during eye movement (Score:2, Interesting)
Re:Very timely write-up (Score:1, Interesting)