1. Zach Van Sickle Alyssa Kaeser
Human Vision
Zach Van Sickle
Alyssa Kaeser

2. Color Blindness
The eye detects three colors: red, blue, and green. All other colors are a combination of varying degrees of these three colors.
Color blindness is a vision deficiency in which the perception of colors is different from one person than that of normal vision.
Color blindness varies in intensity, the most severe cases being those of complete color blindness.
Color blindness is due to an inactive photopigments caused by defective genes.
There are three types of colorblindness, due to which gene is affected.

3. Color Blindness
There is no cure for color blindness. However, people with red-green color blindness may be able to use a special set of lenses to help them perceive colors more accurately.
Visual aids have also been developed to help people cope with color blindness. There are iPhone and iPad apps, for example, that help people with color blindness differentiate between colors

4. Cataracts
A cataract is a clouding of the normally clear lens of your eye.
Clouded vision caused by cataracts can make it more difficult to read, drive a car (especially at night) or see the expression on a friend's face.
Cataracts are caused in several ways including: age related, congenital, secondary, and trauma.

5. Cataracts Symptoms vision that’s cloudy, blurry, foggy, or filmy
Nearsightedness (in older people)
Problems driving at night
Problems with glare during the day
Double vision in the affected eye
Trouble with eyeglasses or contact lenses not working well
Changes in the way you see color

6. Cataracts
In mild cases, cataracts can be treated with glasses or contacts lenses.
In severe cases, cataract surgery may be necessary to correct vision.
Cataract surgery consists of removal of the outer lens and a replacement with an artificial lens.

7. Rods
Rods: Receptors in our eyes that are highly perceive to light and dark
These perceive motion the most and are much more numerous than cone receptors.
These are most responsible for our night vision because they perceive light well.
Rods are more numerous in our periphery,
which is why we can see objects in dim light
better when looking beside them instead of
directly at them.

8. Cones
Cones: Receptors in our eyes responsible for the perception of color
These are less numerous in the eye than rods and only work well in bright light.
This is why we don’t see color in dim light; however, cone receptors allow us to detect finer details than rods allow.

9. Binocular Vision
Binocular Vision- Vision wherein both eyes aim simultaneously at the same visual target
STEREOPSIS: (or stereoscopic vision) vision wherein two separate images from two eyes are successfully combined into one image in the brain.

10. How it Works
Both eyes aimed at the same target perceive two similar(but not identical) images
The brain sorts out the two different images and combines them into one.
Because the combined images are different, the resulting image has an added depth dimension

11. This is how the brain takes the two different images and combines them into one three- dimensional image

12. Common Tasks that Require Binocular Vision
Throwing, catching or hitting a ball
Driving and parking a car
Planning and building a three-dimensional object
Threading a needle and sewing
Reaching out to shake someone's hand
Pouring into a container
Stepping off a curb or step

13. Review Questions
T/F: The eye detects red, blue, and purple as it’s base colors.
T/F: There are visual aids to correct color blindness
T/F: Cataracts is an inflammation of the eye
T/F: A symptom of cataracts is a glare during the day or while driving at night.
T/F: There is no treatment or aid for cataracts.

14. Review Questions
6. What in our eyes is responsible for perceiving light and dark?
7. What in our eyes is responsible for the detection of color?
8. T/F Humans have stereoscopic vision.
9. What organ in our body merges images from each eye into a three-dimensional image?
10. T/F We can have proper depth perception with one eye closed.

15. Works Cited
Facts About Color Blindness. (2015, February). Retrieved February 23, 2017, from
Kozarsky, A., MD. (2016, September 24). What Are Cataracts? Retrieved February 24, 2017, from
Cooper, R. (n.d.). What is Binocular Vision? Retrieved February 24, 2017, from
Chudler/University of Washington, E. H. (n.d.). Neuroscience For Kids. Retrieved February 24, 2017, from