When You Sense Nothing At All

Blogging is new to me. I’ve been reading blogs for quite some time about the new restaurant in the block or movie reviews but I’ve never attempted to write my own blog. I just don’t have the courage to write something and technically publish it to the online users all over the world. But well, for me, anything new is an adventure so I’ll give this a shot.

It’s pretty fun to explore using our senses especially our eyes. Vision is a very special gift to every human being. With the emergence of technology, we still have to take care of our eyes. Our eyes take us to many places. I’d like to focus on visual perception in most of my blogs because I am somehow frustrated with my visual capacities. From the age of 4, I’ve been required to wear corrective glasses. 18 years later, I can hardly see without my contact lenses or my high-graded glasses. I was wondering if it was only because of my condition that I hardly spot differences in two similar pictures or situations or it’s common among individuals. A lot of people would say that they have clear vision but does that guarantee that you perceive everything that is around you especially improbable changes?

Let me introduce to you the concept of change blindness. It is a trend where people unable to notice changes occurring to objects within their visual fields. Some would say that their eyes are just dishonest with what they see but is that true? I would say that I know a few gifted people who are very keen to these changes especially when they are familiar to the environment like their own rooms or workplace but most people aren’t. Are you susceptible to change blindness?

A study done 2004 suggests that a lot of people hardly notice changes in their environment which is improbable. Lead researcher Melissa Beck, PHD, of George Mason University conducted an experiment which backs up the concept of change blindness. She hypothesized that people are more likely to notice changes they can logically anticipate than improbable ones. People tend to closely monitor properties that are likely to change. To further test this hypothesis, the researchers took photos of 10 familiar places and altered each photo twice, one with a probable change and the other with an improbable change. After which, the researchers showed the participants 20 photos, 10 original, 5 probable alteration and 5 improbable alteration. The researchers asked the participants to come up with a story about the scene showed to them. Half way through the experiment, the altered photo would replace the original photo in the computer screen. The researchers also grouped the participants into performance group and prediction group. The performance group weren’t informed that there will be a change in the picture while the prediction group was informed. The performance group only noticed about 40 percent of probable changes and 20 percent of improbable change while the prediction group noticed 60 percent of improbable and 70 percent of probable changes. This clearly illustrates that we are keener to probable changes but sometimes, we tend to overlook at these changes. It is harder to notice improbable changes even when we think that it’s very easy to detect them.

I find this study to have many practical uses. In everyday situations, we tend to be confident with what we see in our two eyes but this experiment proves otherwise. It shows that we have less conscious control over what we actually see. One lucky person may have a photographic memory but it doesn’t ensure that he or she can actually detect major and minor changes that happen in the environment. As the article suggest, we might have a rich visual picture of everything but we struggle in details. Are your eyes dishonest? Check: http://www.nytimes.com/interactive/2008/03/31/science/20080331_ANGIER_GRAPHIC.html#step1

Also watch these videos about change blindness.

http://www.youtube.com/watch?v=mAnKvo-fPs0

http://www.youtube.com/watch?v=OrA-69hJlEg

Goldstein, E. B. (2010). Sensation and perception (8^th ed.). California, USA: Wadsworth.

Greer, M (2004) People don't notice unexpected visual changes--though they predict they will. Monitor on Psychology, 35 (8), page 10. Retrieved from http://www.apa.org/monitor/sep04/visual.asp

Prior to learning the topics in Perception, we, people think that we see objective reality through our eyes. Yet we’ve learned that change blindness occurs and this is when we fail to notice or detect changes in the scenes where we’ve set our eyes upon for a brief period of time. It would seem logical to think that small modifications or tiny changes would be difficult to detect while larger ones would be more noticeable and may not even be subjected to the phenomenon of change blindness. However, the latter assumption was contradicted by Rosielle and Scaggs’ research findings (2007).

In the pursuit to investigate the ability of people to detect large changes in the scenes and at the same time to measure change-blindness blindness, the study involved a sum of 144 students; 48 participants randomly assigned to each of the three conditions and who reported to have normal or corrected-to-normal vision and to have attended the university for at least 2 years. The three conditions are: 1.) Change-Detection group wherein the task of the participants were to study each of the 12 images of their own campuses presented one at a time, each for 20 seconds, and to determine if something is missing, and in case there are any, what were they; also, they were asked to rate their familiarity with the scene and to estimate the number of times per week that they personally viewed the scene in the past academic year; 2.) Familiar-prediction and 3.) Unfamiliar-prediction groups are the other tow conditions. In these conditions, the same task of estimating the percentage of undergraduate students who would notice the changes (the same set of stimuli were used for all the conditions including the first one); the only difference in these two prediction groups is their familiarity to the scenes. Only those who did not attend the universities featured in the stimuli were included in the unfamiliar-prediction group, unless otherwise. In my opinion, the researchers were able to conduct the study very well through these methods and strategies that they had employed. In addition, it was a good idea to analyze how familiarity would affect change-blindness blindness.

To continue,the stimuli used in the study were 24 color images of specific locations from two college campuses. These stimuli were presented in color on a 17-inch color monitor with a resolution of 800x600. An altered version of each scene was edited to digitally remove prominent objects/features in the scene (i.e. buildings, landscapes).


As mentioned, the stimuli did not only include large changes, but they were also scenes from familiar environment of the participants. Yes, that’s right! The scenes were even familiar to the subjects thus it could be assumed that the changes would be obvious enough to increase the change-detection probability. Some literature suggests that processing a familiar environment would involve long-term memory. So what if it involves long-term memory? Well, it is actually assumed that long-term memory contains detailed information about objects seen in the past (Henderson & Hollingworth, 2003; Hollingworth, 2004; cited in Rosielle & Scagss, 2007). Melcher’s study (2006) also suggests that the amount of information about a scene stored in the long-term memory accumulates over time— that is increased familiarity— which is probably why the participants in Change-detection and Familiar-prediction conditions of Rosielle and Scaggs’ study were limited to those who had attended the university for at least two years. In addition to this, Atkinson and Shiffrin (1968) also found that increasing the number of exposure improves memory for scenes; thus multiple exposures to the environment, like going to a university campus on a regular basis, would seem to lead to a robust and also a detailed memory representation of that environment. Why do we say that familiar environment and scenes are stored in the long-term memory? That is because the features of such environment are said to also have practical uses beyond our recognition, such as being landmarks, that gives it a good reason for us to unconsciously encode it in our long-term memory and in turn be a “good candidate for immunity to change blindness” (Rosielle & Scaggs, 2007).


But is this really the case? As mentioned above, we would suppose so.

In fact, in the prediction of the study which measures change-blindness blindness— that is in short explanation, the overestimation of the ability to detect changes in scenes when in fact change blindness does actually occur— it has been found that both the familiar and unfamiliar group of participants overestimated the easiness of change-detection in stimuli that were also presented in the change-identification condition. Both of the groups predicted better performance compare to the actual result of the change-detection group’s performance. However, the familiar-prediction group’s estimate was relatively more accurate. Interestingly, the unfamiliar group’s prediction was correlated to the area of change (r= -.811, p<.01), meaning this groups’ prediction of difficulty is based on the size of the object that was changed or removed (Rosielle & Scaggs, 2007).

But then again, is this really the case? The answer…? A big NO!

As implied in the previous paragraph, participants in the change-detection condition had actually failed to detect 81% of these “big changes” despite reports of high familiarity and recognition of these familiar locations 97% of the time.

A plausible explanation why people are unable to see changes, even such larger ones discussed in the literature, is that people are not confronted to such changes in real life (Rosielle & Scaggs, 2007). Buildings and landscapes such as fountains don’t disappear or appear in just a blink of an eye; and so it might be the case that our visual system did not just evolved in such way which gives us difficulty to perform detection of the similar changes. Without movement or motion, our visual system cannot perceive changes in the stimulus or in the environment (Goldstein, 2010).

Overall, the study was remarkable as it was able to examine not only the change blindness of people, specifically to big changes, but also how we could be blinded by our believes and senses. Reading this study had also made me think if change blindness could be associated to the notion that people are resistant to change in a social level. Could there somehow be a link between these?

Finally, as this study simply suggests that people are not that aware of his and her environment though they may subjectively think they are, it makes us-- or at least me-- wonder more about our "real world" and if there really is an objective reality. Is there really an objective reality? Who knows (when the study had just shown how vulnerable we are to "trickery"!)???

...So if you thought you’ve seen it all, you better think and look again!


References:
Goldstein, E. B. (2010). Sensation and perception (8th ed.). California, USA: Wadsworth.

Rosielle, L. & Scaggs, W. J. (2007). What if they knocked down the library and nobody noticed? The failure to detect large changes to familiar scenes. Memory. 16 (2). 115-124. Retrieved from EBSCOhost.

Change in Scene Detection: Who’s Better?

The study by Smith and Milne (2009), studied change blindness or the phenomenon in which in a given visual scene, there is a limit to the number of items one can attend to, among the individuals with autism. The results revealed that the Autism Spectrum Disorder (ASD) group significantly identified more errors in a film with discontinuity errors than the Typically Developing (TD) controls. It has been identified that individuals with autism can look at the details that the typical observers usually undermine. In both groups however, they were able to identify more central errors than marginal errors though it is larger in the TD group. There was also no difference in the number of social and non-social errors identified by the groups. Social stimuli are those which can easily be noticed and captured even by the children, actor in this particular study. The results indicated that the ASD group showed enhanced visual function, and lack of filtering of visual information. In other words, these individuals are more sensitive to even simple visual stimuli.

The independent variable in the study was the condition of having an autism or not having an autism while the dependent variable was the number of errors, which could be central or marginal, social or non-social, identified in a movie where continuity errors were deliberately introduced.

There were 15 adolescents in the ASD group, and 15 in the TD group who participated in the experiment with their informed consent. These participants were diagnosed using the DSM-IV criteria. 20 Short clips were created. 16 of which contained specific continuity errors: 8 were actors(social) and 8 were objects(non-social); 8 were central and 8 were marginal errors. Central errors are those contextually relevant with the clip content, while marginal ones are those contextually irrelevant. Participants were told that a film would be shown to them and that they needed to spot the mistakes in relation to the clips created. After watching each clip and the film is paused, participants were asked if they noticed some mistakes and describe what happened. After this, two information questions were also asked for them to focus also on the content. The experimenter read the questions loud while these questions were seen on the screen. The participants needed to write down their answers on the booklet provided. The experimenter checked if they had answers for each question. Then, the results were taken and interpreted. The interpretations were attested by the two chi-square analyses comparing the number of errors detected by each group.

Comments:

The study is very interesting and socially-relevant because it helps to explain the situation of the individuals with autism. In my view, our society is very discriminatory that less dominant ideas and behaviors are often stigmatized just in the cases of the individuals having autism. The socially-relevant part of this study is that people are not homogenous in looking at things. Therefore, through this experiment, we are enlightened to respect and understand people who do not behave with the dominant ideas. We are able to understand and explain the differences scientifically.

I do not have any problem when it comes to the participants since the mean chronological age of the two groups had a very small gap. Age could be a great factor in visual experiments. Most importantly, ethical considerations were emphasized. Ensuring that the participants focus not only on the superficial aspects but also on the content of the film, added to the validity of the research.

Source:

Smith, H. and Milne, E. (2009). Reduced change blindness suggests enhanced attention to detail in individuals with autism. Journal of Child Psychology and Psychiatry, 50:3 pp 300-306.

The media tells us that a beautiful face stands out in any crowd. That is why they were able to sell millions and millions of beauty products for a lot of women aching to catch a guy’s attention. However, what they offer are long term solutions wherein you have to wait for months to see that stunning result. That means, having to wait for long months just to get your crush to notice you. But worry no more because a quick solution lies in facial expressions. With just a twist of your lips, eyes and cheeks, you will get that eye-catching look in seconds.

According to neuropsychological and cognitive studies, facial expressions are a special kind of stimulus for perception because they give out information with adaptive function for social interaction. They can also give insights about the motivational state and intentions of others which in turn, guides our expectations and actions towards people (Calvo, 2008). Contrary to popular belief that happy expressions are more noticeable, a study entitled The Face in the Crowd Effect: Anger Superiority When Using Real Faces and Multiple Identities (Pinkham, et. al, 2010) showed that angry expressions are more easily and accurately recognized in a crowd of other faces. This phenomenon is termed as the “Face in the Crowd Effect (FICE)” or the “Anger- Superiority Effect” which poses evolutionary advantage in quickly locating and recognizing possible threats in the environment. Specific neural modules such as the Amygdala is said to be involved as it specializes in processing faces and threats.

The FICE was tested through a visual search paradigm like when searching for a particular person in a crowd of people as in Where’s Wally? (Goldstein, 2010). Instead of using schematic stimuli, validated veridical photos and heterogeneous faces were used to provide a more realistic crowd. 26 undergraduate students from the University of Pennsylvania participated in the study. 54 matrices containing 9 faces with the same expression (e.g. all happy, all sad, all neutral) and 108 matrices containing 8 faces with the same expression and 1 target face differing in expression were shown in a random order. The participants responded whether all faces showed the same expression or not. Their responses and their reaction times were recorded and analyzed.

Though the study used a relatively small sample, results were consistent with studies using graphic stimuli (not real faces). Angry faces were found more quickly and accurately across a crowd of other faces compared with happy faces. This tells us that processing threatening stimuli have a strong advantage relative to nonthreatening stimuli in the environment.

Also, if you really want to get someone to notice you especially when you are in a place with a lot of people, try sporting that angry expression. A word of caution though, reactions of the people who would see may be different from what you expected. Or, if you want to stand-out in your friend’s wacky picture, wrinkle that nose and expose your teeth for that best angry face.

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Calvo, M. G., Nummenmaa, L., & Avero, P. (2008). Visual Search of Emotional Faces : Eye-Movement Assessment of Component Processes. Experimental Psychology, 55, 6, 359-370. Retrieved from EBSCOhost.

Goldstein, E. B. (2010). Sensation and perception (8^th ed.). California, USA: Wadsworth.

Pinkham, A. E., Griffin, M., Baron, R., Sasson, N. J., Gur, R. C. (2010). The Face in the Crowd Effect: Anger Superiority When Using Real Faces and Multiple Identities. Emotion, 10, 1, 141-146. Retrieved from EBSCOhost.