For my one psychology class I am required to participate in research hours.  One study I did required me to view many different patters of stimuli while they measured my brainwave activity.  Before beginning the experiment they researchers wanted to test my vision to make sure I could see the stimuli on the computer screen.  I began by using the tests we used in class to check for colorblindness.  I was able to detect the number present in each of the patterns, so I am not colorblind.  After that I was asked to read the letters on the chart that is used by doctors to test our vision, something I am sure everyone has had to do before.   Whenever I was required to do this before I had no issues, and was told I had 20/20 vision. With both eyes it was very easy for me to read the bottom line with the smallest letters.   Next, I was asked to cover my left eye and attempt to do the same thing.  I was able to do this without any difficulty as well.  Then I had to cover my right eye and read with only my left.  For the first time in my life I couldn’t do it.  Everything was slightly blurry so I was not able to determine what letters were there.  At first I was concerned, I was wondering if my vision was getting worse, but then they told me that there was no problem at all.  My vision with my right eye was 20/16, my left eye was 20/20, and together they gave me 20/20 vision.  Before I was very confused by what this meant, but with what we learned in class I was able to make sense of this.  20/20 vision means my vision is what it should be.  I can see from 20 feet what I should be able to.  20/10 vision in my right eye means I can see from 20 feet what most other people can only see from 10 feet away.  What we learned in class made me realize there was no need for concern with my left eye being weaker than my right eye.