Color Vision and Evolution
While color vision is taken for granted in everyday life, it, in fact, served a crucial role in the progress of the humankind at the dawn of its development. As predators, our ancestors needed color vision to detect and identify various objects, including prey. Therefore, it was crucial for people at the dawn of their development to acquire color vision.
The presence of color vision is also crucial for a herbivore. For instance, the specified property will allow detecting the presence of a predator fast and, therefore, escaping successfully. Thus, the evolution of color vision should be viewed as the process of adapting toward the changes in the environment. In fact, one of the theories, known as the Fruit Theory, points to the possibility of color vision development as a response toward the need to identify ripe fruits for further consumption.
The inability to see colors or the quality of viewing the world in a different chromatic scope than the rest of people, therefore, created a range of impediments to people in the past, thus, leading to a greater number of accidents and deaths. Furthermore, when considering the benefits of dichromatic vision over trichromatic one, one must mention that the latter does not allow defining color-camouflaged stimuli in the same way as the former (Land 15).
Therefore, the development of color vision should be deemed as a crucial step in the evolution of both herbivores and predators. The acquisition of the ability to distinguish between different colors served as the tool for not only masking oneself successfully from larger predators but also determining the presence of a possible prey and, therefore, satiating oneself. Consequently, it must be admitted that the acquisition of the ability to see should be viewed as an essential step in the evolution of the humankind (Land 21).
Illusion of Movement
Allowing one to observe the phenomenon of the rotation motion, the Prima Belstaff illusion is often viewed as a prime example of optical illusions. When focusing on the black dot in the center and moving one’s eyes closer to it, one is likely to be under the impression that the two circles around it move. The specified phenomenon can be explained by the fact that the peripheral vision perceives the identified elements as blurred, thus, preventing one from determining their actual position in the circle. It is remarkable that, even when the elements of the circle are misaligned, the effect thereof persists, compelling one to believe that the identified items move. The observed phenomenon, in turn, can be explained by the gestalt principle of common fate (Gregory 4). The responsiveness of direction and motion can also be viewed as one of the primary factors behind the presence of the identified illusion.
In fact, there are similar illusions the presence of which is defined by the specified factors. For example, the images that are typically defined as the peripheral drift illusions, e.g., Rotating Snakes by Kitaoka Akiyoshi, also imply that the elements of the image should be misaligned with the orientation of the object that is in the focus of the viewer’s attention. As a result, the effect of rotation remains throughout the observation of the said images. The specified illusion can be located at the following link.
A closer look at the subject matter will show that, while the two circles remain immobile, they seem to be rotating counter-clockwise. The specified phenomenon is also linked directly to the peripheral vision of an observer. Furthermore, the phenomenon can be explained by the fact that the concept of motion is perceived as the shift from dark to light. The picture, in turn, incorporates interchangeable light and dark elements, which contribute to the creation of a motion illusion successfully. As a result, the observer perceives both elements as consistently moving even though the picture is completely stable.
Quiz: Color Vision
Trichromatic Theory of Color and the Opponent-Process Theory of Color
There are several theoretical frameworks that allow one understand the concept of color vision. The trichromatic theory of color is, perhaps, the most common one; it was suggested by Thomas Young and Hermann von Helmholtz, and it implies that one is able to see colors because of three types of color cones (red, green, and blue). Underdevelopment of some of the cones results in vision issues, particularly, in color blindness.
There are other ways of interpreting people’s ability to see colors, though. The opponent-process theory of color, in turn, suggests that the process of color transduction as the basic analysis of the essential visual information starts with retina, then proceeds to the bipolar cells area, and then finally reaches the ganglion cells. As a result, the color pairs that are identified in the process are identified as red and green, blue and yellow, and white and black.
Seeing that the concept of vision is rather intricate and complex, claiming that one of the theories is entirely correct, whereas the other is completely wrong, would be unreasonable. At present, though, the trichromatic theory is viewed as the most common.
One Retinal Color Vision Deficiency and One Brain Color Vision Deficiency
The phenomenon of color blindness mentioned above can be deemed as the primary example of a retinal color vision deficiency. As explained above, the inability to see specific colors is typically attributed to the damage of cones that are considered to be the primary mechanism for color identification in people. Therefore, the mechanical damage to the cones is defined as a retinal color vision deficiency that ultimately leads to developing the inability to see specific colors.
As far as the brain-related deficiencies in seeing color are concerned, cerebral achromatopsia is traditionally listed among the primary examples thereof. The identified phenomenon implies that the color vision of an individual is impaired not due to the mechanical damage of their retina but because of the malfunctioning of the cerebral cortex of their brain (Millodot 44). It is remarkable that patients with cerebral achromatopsia may fail to notice the development of color blindness (Millodot 44). However, similarly to inborn color blindness that was caused by the damage to the patient’s retina, the inability to see color that was triggered by cerebral achromatopsia cannot be treated successfully, either.
Two Theoretical Explanations for Motion Perception
The phenomenon of motion perception can be explained from several standpoints, hence the presence of numerous theories that allow interpreting the subject matter. The process of identifying motion can be described as the identification of the velocity with which specific objects move based on the visual input and the associated factors. However, seeing that the very concept of motion is relevant to the viewer and the movement thereof, several perspectives of motion interpretation exist. The neural field model for motion perception should be mentioned first as one of the most common tools for describing the phenomenon of motion as people see it. The specified approach implies viewing the perception of motion as the process of stimulating cells in the visual cortex. Another framework for understanding the concept of movement involves the application of the approach known as the Three-Systems Theory (TSS). TSS states that people perceive motion in its three primary manifestations, i.e., luminance patterns, modulations, and the salience map (Warren and Wertheim 114).
Brain Pathways Involved in Color Perception and also in Motion Perception
Surprisingly enough, to distinguish colors and motions, similar brain pathways are used. From an anatomical standpoint, the pathways for visual perception incorporate the optic nerve, the thalamus, and the visual cortex. It should be borne in mind that there is extensive evidence gathered from the anatomical, neuropsychological, and psychophysical functioning of the human body, which point to the fact that motor and visual information sets are analyzed differently in the human brain, there are indications that some of these processes share a significant number of similarities. For example, one of the foundational studies addressing the subject matter point to the fact that color affects the perceived direction of motion. Therefore, there is an evident connection between the two signals as far as the perception thereof by people is concerned. The following research indicated that there is an even greater connection between the phenomenon of motion and the concept of color as people see it. To be more specific, it was proven that there is an opportunity to capture color borders with the help of motion. Thus, the process of data transfer from the optic nerve to the thalamus, and the visual cortex is similar for visual and motion-related data (Warren and Wertheim 102).
Reflection: A Psychologist and a Philosopher. Is What We Are Perceiving Really out There?
Although the ability to see objects and colors is often taken for granted, the identified ability has been the subject of numerous discussion and studies. Therefore, the perspective of a philosopher on a particular vision-related issue is likely to be strikingly different from the one of a psychologist. The specified issue is especially peculiar when considering them from the perspective of color perception. The points of argument are numerous and inspiring; however, the possible differences in color perception are, perhaps, the most fascinating issues to address. To put it simply, it is most interesting to find out whether the colors that one person sees are entirely similar to how they are perceived by others. In other words, determining whether the red color that one person can see is exactly the same as what others can observe seems to be very interesting, although hardly attainable. Indeed, it is practically impossible to determine with mathematical precision whether the red color than one sees is the exact red color that the others do. The corresponding psychological and philosophical perspectives on the subject matter are, however, even more exciting than the discussion of the dilemma, in general.
The psychological perspective of the specified dilemma is strikingly different from the philosophical one. as explained above, it is barely possible to define with mechanic accuracy the actual similarity or difference between the specifics of people’s visual perception, color not being an exception. Therefore, from a psychologist’s standpoint, the ability of a person to distinguish between different colors must be interpreted as an individual reaction to a specific set of stimuli. The specified point of view suggests, therefore, that the identification and perception of color as one of the crucial components of one’s ability to perceive visual stimuli should be individual and, thus, may imply significant differences in the interpretation of the visual data.
In other words, what some people see as a darker shade of red others might see as a lighter one. In fact, the psychological perspective of the problem as the one that implies viewing the problem from an individualist perspective may even suggest that people might see colors differently, and not only shades thereof. In other words, , theoretically, it could be assumed that what some people see as red others may see as green. In fact, the identified idea of rendering people’s ability to visualize specific data is supported by the presence of the disorder known as color blindness, which literally proves that people do see colors differently. E.g., what a person with regular vision defines as red, a person with deuteranomal vision will see as dark-yellow (Millodot 16).
A philosophical perspective of the problem, in turn, will require a more generalized approach toward exploring the issue. For instance, to answer the question of whether people see a particular color in the same way, a philosopher may need to deconstruct the very concept of a color so that the process of the information input and its further analysis could become more understandable and, therefore, easier to analyze. Therefore, one will have to redefine color. According to the existing viewpoints of the subject matter, a color can be deemed as the information that an individual receives based on the wave length of the visual data. Seeing that the specified characteristics are stable and unchangeable, a philosopher is likely to concede that people see colors in the same way, and that a specific color is interpreted in the same way by anyone (Gregory 27).
The specified problem can be deemed as the primary example of an intersection between psychology and philosophy. In fact, the idea that the objective reality may be an imaginary concept that exists only due to the unique way of processing the input by the human brain has led to the development of the principles of Solipsism in philosophy. According to the existing definition, the subject matter implies that the reality is merely the projection of one’s self onto the information that is perceived and processed by the human brain. In other words, the philosophical theory of solipsism implies that only the existence of one’s brain can be deemed as certainty, whereas the rest of the reality can be questioned and, therefore, should be regarded as dubious (Bayne et al. 214).
It should be borne in mind, though, that, when viewed through the lens of philosophy, the concept of seeing and interpreting color is even more profound and intricate than described above. The issue can be explored from the standpoint of Eliminativism, which is typically conflated with the philosophy of Subjectivism. The former framework implies that the phenomenon of color is not an intrinsic characteristic of objects but, instead, a description that is based on the unique way in which people perceive external stimuli and interpret them. In other words, the Eliminativist approach states that, as such, objects do not have any color (Bayne et al. 210). The Subjectivist perspective, in turn, makes one view the process of defining color as the process that hinges primarily on the individual properties of one’s eyes. Therefore, the identified perspective suggests that the interpretation of the presence of objects and colors in reality is purely subjective, and that people, in fact, can see things differently from each other without even knowing it.
Works Cited
Bayne, Tim, et al. The Oxford Companion to Consciousness. OUP, 2014.
Gregory, Richard L. Eye and Brain: The Psychology of Seeing. 5th Ed. Princeton University Press, 2015.
Land, Michael F. The Eye: A Very Short Introduction. OUP Oxford, 2014.
Millodot, Mitchell. Dictionary of Optometry and Visual Science. Elsevier Health Sciences, 2014.
Warren, Rik, and Alexander Wertheim. Perception and Control of Self-motion. Psychology Press, 2014.