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Color is all around us in this world. In actuality color is different waves of light at different lengths that are reflected off a surface and into our eyes. Within the eye, cones and rods absorb light and send a signal to the brain, allowing us to see the world around us. As we experience more of the world around us, specific objects become associated with specific colors. This is called a memory color according to Christoph Witzel and Karl Gegenfurner in their article, Color Perception: Objects, Constancy, and Categories. In this project, I wish to appeal to that color memory with a drawn picture of fruit. The twist I wish to put on this project is that the image will be drawn using an inverted pallet in hopes of making the image clear only in an afterimage. Following will focus on the physiological happening when an after image is formed, to include: how the sensory cells of the eyes differ from other sensory input calls and how the stimulus is translated into an action potential and how the.
The sensory cells in the eye are called photoreceptors and are subdivided into cones and rods. These are located on the back of the eye at the retina. In other sensory organs, when an input is processed, the cell will begin to open channels in the cell membrane, causing an action potential to take place. In the eyes, when light waves interact with the cone and rods, an action potential occurs with the closure of channels into the cell. As more light is absorbed by the cell, it becomes “bleached” or over-stimulated (Betts, 2022). When this occurs, those cones can no longer transmit a signal to the brain. If the individual is exposed to white light after this “bleaching” occurs, then all the non-simulated cones will be what absorbs the light and a phenomenon called an afterimage can be seen (Gersztenkorn, 2024).
In the article: Color Perception: Objects, Constancy, and Categories the authors state that memory color is used as a survival method to distinguish items. The example that they state is that of a banana. If the banana is the memory color yellow then that tells us that the item is ripe and ready to eat. If the fruit is green or brown then our learned experience is that the banana is not ready to be eaten or that it is too far gone to consume. Memory color is also used to communicate and teach other individuals this information. If an individual has never experienced a banana but they were told that yellow is the color of a safe to eat fruit then when they do first experience a banana they will know if it is ready to eat.
The cones in the human eye come in three variants: red, green and blue. This can also be described as short, medium and long in reference to the wavelength of the color. This is described as trichromatic vision in regards to the three types of cones. An individual with color blindness or dichromacy describes an individual with only two types of cones. When looking at the genetic sequencing related to cone construction, it appeared that the plans for the blue cone were at a distance from the plans for the red and green cones. This has led, as stated in Cones and Color Vision, Jeremy Nathans and colleagues to speculate that the development of the different red and green cones happened in the recent past.
In an individual with color blindness, their cones are not able to distinguish the different wavelengths that stimulate the cones in the eye. When a green light enters the eye, the green cone will be activated but so will the red cone because in the development of the eye, the red and green cones developed a similar receiver (Purves, 2024). As the action potential travels from the cone to the ganglion cell and up to the brain, the signal is read as both red and green. This makes the colors indistinguishable from the other.
As the physiological way we perceive color has evolved, so has the memory color evolved with it. That is why i have chosen to create a reverse image of fruit the after image will your memory color showing that when objects seem out of place in the world, the mind notices
Bibliography
Gersztenkorn, David, and Andrew G. Lee. “Palinopsia Revamped: A Systematic Review of the Literature.” Survey of Ophthalmology, vol. 60, no. 1, Jan. 2015, pp. 1–35, https://doi.org/10.1016/j.survophthal.2014.06.003. Accessed 21 Nov. 2024.
Gordon Betts, J., et al. Anatomy and Physiology 2e. Openstax, 2022, openstax.org/details/books/anatomy-and-physiology-2e.
Purves, Dale, et al. “Cones and Color Vision.” National Library of Medicine, Sinauer Associates, 2012, www.ncbi.nlm.nih.gov/books/NBK11059/. Accessed 21 Nov. 2024.
Witzel, Christoph, and Karl R. Gegenfurtner. “Color Perception: Objects, Constancy, and Categories.” Annual Review of Vision Science, vol. 4, no. 1, 15 Sept. 2018, pp. 475–499, https://doi.org/10.1146/annurev-vision-091517-034231.
The perception of color is how different lengths and light waves reflect off surfaces. Photoreceptors absorb and read the light to tell you what colors there are. There are cones in the retina that make it able for you to see color and rods to help with dark and light vision. When these things are introduced to light; it creates an action potential. When these rods and cones get overstimulated by the light they become bleached. After the bleaching happens the cones can’t send signals to the brain. If they are still exposed to white light then the non-stimulated cones have to pick up the slack. There are three variants of cones in the human eye. There are red, green, and blue cones. These are described as short, medium and long wavelengths of color. People who are color blind might only have 2 of the three cones. With color blindness their cones aren’t able to differentiate different wavelengths. When certain colors enter their eye it will stimulate more than just one cone. When the action potential travels to the brain it is read as more than just one color, this makes it indistinguishable between the colors.