Experiment 1: Dark adoption
I went to the dark room with 15 index cards with the flash flashlight. I placed all the cards over the beam of light. I then started removing one card after another until I could barely detect light: that was the absolute threshold that stimulated my rod receptor. It was about the 10th card. As a result, I remain with five cards. I waited for a few minutes, and the light began becoming brighter. In that case, I added another card, which automatically covered the light completely.
Furthermore, I waited for a few minutes and added the cards one after another and but I couldn’t see any more light. From my experience, when I entered the dark room, my cones were still active, and since don’t detect dim light, my rod receptors were activating slowly. So I was able to see the faint light when my rod receptors perceived the visual at the tenth card. After sometimes, I was able to continue seeing the dim light after I added the eleven card because I did not look directly to the bright light, hence my cones were not reactive. When I added the other cards, I looked at the bright light and thus I couldn’t see any longer because the light did not reach the rods receptors which are responsible for visual light.
Experiment 2: Night Vision and the Fovea
I went outside the house on a clear night. There were a few surrounding lights. I started observing the stars, and I Located a relatively dim star that was slight to the right of the focal point of my gaze. When I suddenly shifted my gaze to look directly at the star, it disappeared. My observation was that since I had exposed my eyes initially to bright light, the lights reached the fovea region, which has more concentration with cones. While I shifted my eyes to the dim light, the adaptation of the rods receptors took quite a long. Hence I could hardly see the dim star.
Experiment 3: The Autokinetic Illusion
First, I create a small point of light by using a thin, sharp flashlight. Then, I went into a very dark room and shone the light on the wall about 10 feet in front of me. After a few moments, the light appears to drift and move around slightly. From my observation, one of my eye muscle becomes fatigued and started to cause slight eye movement; this causes the retina to perceive the object movement as actual, thus creating an illusionary change of static objects.
Expriment4: d. Temperature Adaptation
I located three medium-size bowls and filled them with:
(a) Very hot (but not painfully so) tap water,
(b) Icy tap water, and
(c) A mixture of the boiling and freezing water.
Then I arranged the bowls so that my right hand was in front of the cold water, my left hand was in front of the hot water, and the lukewarm water was in the middle. Then, I submerged my hands into the water (right into cold, left into hot) for about 3 minutes. After 3 minutes, I quickly transferred both hands to the lukewarm (middle) bowl. My observation was that my right-hand freeze in cold water, and my left hand was warmer. When I immersed both hands in lukewarm water, my right hand becomes more temperate, and my left hand becomes cooler. I think the reason is that the nervous system stimulates the changes depending on the previous input: this is a result of thermoreceptors (cold and warm receptors) which are rapidly adapting receptors. The brain then perceives the water to be warm because the hot receptors give more information to the brain than the cold receptors.