The purpose of this science fair experiment is to better understand the science behind the reaction time of human beings and what different factors are able to affect the outcomes of it. These factors may be age or different times of the day. In order to better understand this experiment clearly, research was done on subtopics relating to sensory stimulus in the human eyes. These subtopics include the structure of the human eye, the function of the circadian clock, and the performance of the sense of sight. A basic conclusion can be led through the entire spectrum of research, which is that the eyes take in light from where a person is looking and sends it to the brain, which process the final image that the person is able to see. The …show more content…
Inside of the retina, there are two types of photoreceptor cells. One is called a cone, and the other is called a rod. “The rods, which are more numerous than cones, are responsible for our vision in dim light but don’t function in bright light. Rods account for our night vision but cannot distinguish color (Douma, 2008).” The cones differ from the rods, and their function is the opposite. “Cones are active at high light levels and allow us to see color and fine detail directly in front of us. They can adapt to widely varying colors and illumination levels, but don’t work well in low light (Douma 2008).” Color is determined through a property called retinotopic organization. This process involves the signal from the retina being analyzed by nerve cells, which then travel to the brain eventually to be divided into several pathways.“For example, visual signals from the photoreceptors pass to retinal ganglion cells, which code color information, and then to the lateral geniculate nucleus (LGN) in the thalamus, and onwards to the primary visual cortex (Douma, 2008).” In conclusion based off of this research for this subtopic, the property of retinotopic organization is depicts on how color is determined through the senses produced by the rods and