Change Blindness: The Ability and Inability to Detect Change
1CHANGE BLINDNESSRunning Head: CHANGE BLINDNESS Change Blindness: The Ability and Inability to Detect Change Brian Andrew Wong Marshall University Experimental Psychology PSY 323 – Section 202 Professor Dr. Nicholas J. Kelling Thursday, April 28, 2011
2CHANGE BLINDNESS Change Blindness: The Ability and Inability to Detect Change Change blindness is the phenomenon of individuals not being able to visually recognizetwo changes that occur in front of them. The failed notice of change can be from a change ofcolor or change in position. Often, this occurs when there is a disruption, such as an eye blink(Werner & Thies, 2000). Often the change becomes obvious after the change is shown to orrecognized by the observer (Blagrove & Wilkinson, 2010). Some notice the changes, whileothers do not. One area of change blindness that has received some research is magic. Themagician tries her or his best so that the audience does not notice the change and that in the endthere will be an illusion created. The magician basically misdirects the attention of the audience.Another area of study in change blindness is detecting and identifying changes that occur innaturalistic scenes. When it comes to experts and novices, there has been research as to whetheror not expert knowledge will assist in noticing changes. For example, American football playersare guessed to be better at noticing changes in photographs of football players. There has beenresearch in lucid dreaming and change blindness. Finally, there are a few people who are veryskilled at noticing changes that others fail to see; those diagnosed on the autism spectrum havebeen known to pay attention to detail that their neurotypical counterparts cannot. According to Lamont, et al (2010), there has been interest in the scientific study of magic.They argue that the scientific study of magic is a “misguided area” (p. 16). To establish a scienceof magic, there have been periodical studies by psychologists. A general psychological theoryand a neuroscience of magic are two approaches to the understanding of magic (Lamont et al,2010). In magic, the magician tries to misdirect their audience. Lamont et al quotes Kuhn et al(2008) that misdirection is defined as “the direction of attention away from the method [how the
3CHANGE BLINDNESStrick is done],” and that several “methods involve attentional capture, in which attention is pulledaway by an irrelevant task” (Kuhn et al, qtd in Lamont et al, 2010, p. 16). Most magic theoristsmake a very clear difference of “crude distraction and effective misdirection” and thusdistractions have little relevance to misdirection. Magicians often try to not use a crudedistraction to direct attention. Scientists have shown interest in this. In magic, misdirection aimsto direct “attention away from the method by naturally directing attention toward what is mostrelevant to what the audience sees as the trick” (Lamont et al, 2010, p. 17). One example of thisis a magician asking someone to choose a card from the deck and to shuffle it. The magiciandirects their attention by commenting on that the deck was shuffled thoroughly. Other ways thatthe magician can direct attention is their gaze, looking during certain times at different places.There has been failure to explain magic in a scientific theory. “The potential and purpose of ascientific theory of magic is simply unclear and that neither magic nor its apparent principlesshould be treated as distinct subjects of scientific inquiry” (Lamont et al, 2010, p. 18). Lamont et al (2010) say that studying magic in a neuroscientific way is “unwarranted” (p.18) even though others say that neuroscientific study of magic is already more productive (p.19). Neuroscience can offer a better understanding on the perception of magic. The neuralresponse of spectators can be studied. What magicians actually do, will be ignored.Neuroscientific study of magic is very new that “it has yet to demonstrate its value” (p. 19). The psychological study of magic has brought upon discussion. However, there isquestion on what the magician does and how the audience perceives the acts of the magician. For those who have a specific expertise in a certain domain, are they more likely to see achange in an image? For example, would an expert player of American football recognize adifference in two photos of football game of a player? Werner & Thies (2000) refer to an
4CHANGE BLINDNESSexperiment of German football players who had never viewed American football. Theexperiment wanted to determine whether the expert football players could detect more changesthan the participants with no experience playing football. Thirty pairs of color images wereshown to the participants. The pictures, taken from video tapes directly, were of scenes from thefootball game, bird eye views of playing formations, and traffic-related scenes (cars on the street)for the control group. The pair of the original image and the altered image was shown together.The study concluded that the expert football players had better advantage of noticing the changesin the images than the novices in the study. When we dream, there are times when we wake up and find the dream weird, or bizarre.Blagrove & Wilkinson (2010) say we tend to notice that bizarre happenings of that dream, whenit comes to dreaming in general. They believe that this ability to notice the bizarre happenings ofour dreams is due to change blindness. When we have dreams that we know are happening, theseare called lucid dreams (Blagrove & Wilkinson, 2010). Using the change blindness theory, theyhypothesized “that there is a continuity of cognitive ability in error detection between wakingand dreaming cognition, with individuals who are frequent lucid dreamers having a higherperformance on change blindness tasks than do nonlucid dreamers” (p. 131). Blagrove & Wilkinson (2010) recruited students at Swansea University in Wales, UnitedKingdom as volunteer participants by an advertisement. Thirty-eight students participated. Theywere grouped by frequent lucid dreamers (more than once a month), occasional lucid dreamers(at least one lucid dream in their lifetime), and noncluid dreamers. The operational definition oflucid dreaming in this study was “lucid dreaming happens when you’re having a normal dream,then within that dream you realize that you are dreaming” (p. 131). Participants filled out adreaming questionnaire and were given a change blindness task to do. The task was to detect
5CHANGE BLINDNESSchanges in photographs. The results of this study were that there were not significant differencesbetween the groups, for the number of change blindness tasks correctly answered as well as withthe dream recall frequency groups (p. 132). Autism is a spectrum of disorders that manifests itself in an individual different levels ofdifficulty in areas of communication, social skills, along with behaviors that can seem repetitiveas well as restricted interests; disorders in the autism spectrum include autism, Asperger’sDisorder, and Pervasive Developmental Disorder Not Otherwise Specified (Christ, Kanne &Reiersen, 2010). Individuals on the autism spectrum tend to notice things that others do notusually notice or pay attention to. It is atypical in those with an autism-related diagnosis todisplay attentional control, having “an inefficient attentional spotlight, which results inabnormally broad attentional focus and an inability to filter extraneous stimuli” (Smith & Milne,2009, p. 302). Smith & Milne (2009) conducted a study where participants both with and withoutan autism spectrum disorder were asked to view short films. Errors in continuity were displayedin the short films. The results showed that those on the autism spectrum identified more errorsthan those not on the autism spectrum. “Both groups identified more errors involving centralrather than marginal aspects of the scene, although this effect was larger” with the group withoutan autism-spectrum disorder (Smith & Milne, 2009, p. 300). Change blindness is an interesting phenomenon. It seems that those who are able todetect the changes are those who have expertise in a certain area, or domain, and those in theautism spectrum.
6CHANGE BLINDNESS ReferencesBlagrove, M., & Wilkinson, A. (2010). Lucid dreaming frequency and change blindness performance. Dreaming, 20, 130-135. Doi: 10.1037/a0019248Christ, S.E., Kanne, S.M., & Reiersen, A.M. (2010). Executive function in individuals with subthreshold autism traits. Neuropsychology, 24, 590-598. doi:10.1037/a0019176Lamont, P., Henderson, J.M., & Smith, T.J. (2010). Where Science and Magic Meet: The Illusion of “Science of Magic”. Review of General Psychology, 14, 16-21. Doi: 10.1037/a0017157Smith, H., & Milne, E. (2009). Reduced change blindness suggests enhanced attention to detail in individuals with autism. Journal of Child Psychology & Psychiatry, 50, 300-306. doi:10.1111/j.1469-7610.2008.01957.xWerner, S. & Thies, B. (2000). Is “Change Blindness” Attenuated by Domain-specific Expertise? An Expert-Novices Comparison of Change Detection in Football Images. Visual Cognition, 7(1/2/4). 163-173