Thoughts on Unconscious Perception

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"Thoughts on Unconscious Perception"
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Title: Change Blindness in Genders

Introduction: Change blindness is defined as "the phenomenon where a person viewing a visual scene apparently fails to detect large changes in the scene", or more simply put the inability in visual perception to recognize change in an image. Researchers have found that the change, which occurs during an eye movement, is not detected, and even changing elements that occupy even a fifth of the image can not be recognized. Typically, for change blindness to occur, there is a brief obscuration of the observed image, called a saccade (a.k.a. "mud splash technique"), or other images instigating change blindness use a "flicker" where two different images are exchanged. Our experiment tests to see whether gender influences change blindness and whether males or females appear to notice the change more.

Hypothesis: We predicted that males would have a longer average time to observe the change in the images.
Dependent Variable: Gender is the dependent variable
Independent Variables: same computer used, same web-sites used, same images used, each subject was tested in the same room tested at the same time of day (10:55-12:45) during their lunch, all on school days. Each subject was at least 14 years old but no older than 18, in the 9th through 12th grades at Manual High School.

Subjects: Our subjects were;
- high-school students
- ages (14-18)
- ten males, ten females
- volunteers in different lunches
- found in DuPont Manual High School lunches
- the subjects were in groups when approached, in lunch
- there were 10 subjects in the experimental group and 10 subjects in the control groups

We used:
- The same computer for every subject as well as the same websites, for the experimental images and for the control image.
- Data sheets where we recorded our findings
- We used the same computer every time in the Manual library.

1) Recruit volunteers from lunches during third period (10:55-12:45).
2) Set up website in library at the same computer each time before subjects sit down at the computer or are able to see the screen, and if there is more than one person in the room that will be tested make sure they cannot see the screen our hear the current subjects point out what is changing.
3) Use a stopwatch to time how long it takes each individual to notice and point our what's gradually changing in each 6 images, including the control image, treating it as if it were part of the experimental group, starting from when the image is present and changing on the screen.
4) Record the data and determine whether there is a significant difference between average times of males and females.

Observe charts for complete findings. Since our data was recorded in seconds and was very precise, there were not any modes for any of the images, all of the times were different. There were never any significant differences between the average observation times for males and females, although the males averages for each pictures were usually longer than the females, except for the tourist image where on average girls were slower on detecting the change with the average time (mean) of 28.42 seconds while boys had an average time of 6.74 seconds. Thus, our hypothesis was not exactly right and no obvious distinction between genders can be made about whether one observes change-blindness faster than the other does.

We cannot conclude after performing this experiment that there is a significant difference between genders and their level of change blindness, thus the information we collected from this experiment does not support our hypothesis that males would be more change blind than females. The recorded times were so varied making it impossible to draw a conclusion from such a limited number of subjects. In a future experiment, more subjects should be tested to obtain more accurate results. Also, after performing this experiment, we realized that the subjects may have felt pressured to rush through the test, and wanted to give up out of frustration because the tests were being administered during their lunch time, consisting in 30 minute blocks, and they could easily have felt rushed to go back to class. Under this pressure, interestingly enough, I found that the only subjects tempted to give up were males, although this information is not conclusive due to the limited number of subjects. Due to the several controls in our experiment, we can generalize our findings to the rest of the student population at DuPont Manual High-school, however not the staff or any other students anywhere else because the environment and age could be a factor to change blindness. We did recognize that as each subject proceeded with the change blindness test, on average each time of detection was shortened after they "learned" what to look for, known as what psychologists call "the learning effect"; for example for our female subjects, the average detection time of the first image of the plane was 77.22 seconds while the second image time was 31.59 seconds and so on. Another thing I would do differently about our experiment was that I would somehow show an image that also had the flicker as the control, even though the image wouldn't change. Most people were able to tell within a few seconds that the control wasn't changing because there was no such "flicker" as the experimental images had, while with a few other subjects, it took about a minute or so for them to be confident that it wasn't changing as they thought it was yet another mind trick believe that the outcome of the experiment wasn't evident of change blindness differences between genders because one's level of change blindness is personal, not because of their gender.


More about this author: Callie Gray

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