The Fly in the ointment was the visual crowding of the Visual System
Actually, many people don’t understand their visual system and don’t know how it functions. Most people believe if they can see the world, object clearly that means their visual system is perfect.
However, the Fly in the ointment was the visual crowding of the Visual System.
What is visual crowding? Why it is important in our visual system? And how it functioned? Can it be avoided? We can get the answer in below.
Visual crowding
According to D. M. Levi (2007), visual crowding was defined as the deleterious influence of nearby flankers on visual discrimination. That means, visual object in our periphery version is more easily to recognize if the object was shown in isolation but difficult to identify when there are other objects surrounded nearby. (ECVP (2008)
So, the reason for the study of visual crowding is because it can increase our knowledge on object recognition processes for example, feature integration. (Levi, (2008)
At past, there were lots of theories said crowding is in a multiple levels with explanation. For example, a connection among neurons with nearly tuning characters causes crowding in visual cortex, for instance in V1. However, Zero of past theories can provide adequate explanations for crowding. On the other hand, revealing the neural mechanism of crowing is the most direct way to search for neural locus of crowding (Bi, T. &Cai, P. & Zhou, TG. & Fang, F, 2008)
In V1, there is no distinct in adjusting to the effect among the flanked and unflanked conditions. However, in V2/V3, stronger adaptation effect in unflanked condition than those in the flanked condition was showed.(Bi, T. &Cai, P. & Zhou, TG. & Fang,F(2...
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...ical pathway. In Dorsal pathway, it provides visual information that detects movement of the objects while in Ventral pathway; it provides visual information about recognition of the object. The distinct properties of location (where) and shape (what) are estimates from very differently sized regions. (Majaj, M. J. & Palomares, M. & Pelli D.G.(2004)
Conclusion
Yes, there is nothing perfect in the world, including our visual system. Not just having blind spot, but also visual crowding. Although crowding had been classify into a key fact that how people visually recognize objects,(Pelli, D. G. (2008)however, it cannot be avoided nowadays. We can see that human visual system is very complicated system. It still has a very long distance to find out all details of our visual system. To this end, our psychologists and neurobiologist are fighting for their study hardly.
The ultimate goal for a system of visual perception is representing visual scenes. It is generally assumed that this requires an initial ‘break-down’ of complex visual stimuli into some kind of “discrete subunits” (De Valois & De Valois, 1980, p.316) which can then be passed on and further processed by the brain. The task thus arises of identifying these subunits as well as the means by which the visual system interprets and processes sensory input. An approach to visual scene analysis that prevailed for many years was that of individual cortical cells being ‘feature detectors’ with particular response-criteria. Though not self-proclaimed, Hubel and Wiesel’s theory of a hierarchical visual system employs a form of such feature detectors. I will here discuss: the origins of the feature detection theory; Hubel and Wiesel’s hierarchical theory of visual perception; criticism of the hierarchical nature of the theory; an alternative theory of receptive-field cells as spatial frequency detectors; and the possibility of reconciling these two theories with reference to parallel processing.
In Seeing, Annie Dillard writes about the things people do not see, and the things people choose to see. Dillard does this to make the reader aware of what is around them. People have the attitude of “what you see is what you get.” (Dillard pg. 13) Dillard believes that people do not actually want to see what is really there. That people only want to see what makes them happy. Dillard goes on to discuss all the things we see and do not see, ending by stating “if we are blinded by darkness, we are also blinded by light”. (Dillard Pg.17) Dillard is saying that if you look hard enough there is always something to see.
Another speaker, Margaret Livingstone delves into the visual aspect of our senses. Livingstone mentions how artists recognize things about vision that neuroscientists are not privy to until years later. Livingstone discussed the differentiation between color and lightness, and how the two contribute differently to a work of art. Color is thought of as “comparing activity” whereas light is thought of as “summing them.” Livingstone indicates that the visual system is subdivided into a ventral system and a dorsal system. The ventral system is responsible for object recognition, face recognition, and color. The dorsal system is responsible for navigating through the environment, special organization, and emotional recognition. The ability for humans to see distance and depth is carried via our colorblind part of our visual system. As a result, Livingstone concludes that one cannot see depth and shading unless the luminance is right to convey three-dimensional.
The ‘where visual pathway’ is concerned with constructing three dimensional representations of the environment and helps our brain to navigate where things are, independently of what they are, in space in relation to itself (Mishkin & Ungerleider & Macko, 1983).... ... middle of paper ... ... The 'Standard' of the 'Standard'.
Processing capacity is a very broad and flexible category according to many researchers. In fact, the quote above mentioned suggests that we often fail to notice things that happen just in front of us (unexpected events that are often salient) either because we were completely absorbed by something else or because we had so many things to do at the same time that we couldn’t pay attention to it. We have all at least once failed to see a friend who was waving at us while eating in the cafeteria or walking in a crowded street. The primary question that we should ask ourselves is: how many things can we attend at the same time? The truth is that we didn’t perceive this friend because of a phenomenon called “inattentional blindness”. The problem is that the richness of our visual experience leads us to believe that our visual representation will include and preserve the same amount of detail (Levin et al 2000). In this paper we’ll see the different theories of inattentional blindness, and the classical theories demonstrating this paradigm.
Sajda P. & Finkle, L.H. (1995) Intermediate Visual Representations and the Construction of Surface Perception. Journal of Cognitive Neuroscience, 7, 267-291.
Visual awareness in humans can affect social interaction and knowledge formation. It has always been thought that adults possess better vision than children. In the past it was thought that babies were born without vision and gained it gradually. Most of these perceptions have so far been nullified by modern research. Although the above is untrue, there are still several differences between infants’ and adults’ vision. The eye of the infant is less than half the size of an adult’s. Considering that visual ability is related to eye size, in infan...
middle of paper ... ...137-137. Human Perception and Performance, 15(3): 448-456. Eriksen, C. W. & St. James, J. D. (1986). Visual attention within and around the field of focal attention: A zoom lens model.
From one end, what we see right away tends to be the natural obvious. We notice these things right away because they are in plain sight and we are used to seeing them every day without thinking or analyzing what we perceive. For example, the grass is green and the sky is blue. Dillard speaks of a time where she saw a frog and because of the surroundings it was in and its appearance it was hard for her to recognize it for what it was. Dillard described, “I once spent a full three minutes looking at a bullfrog that was so unexpectedly large I couldn’t see it even though a dozen enthusiastic campers were shouting directions… When at last I picked out the frog, I saw what pain...
...ecause through sight, humans have the ability to see what they choose and can omit what they do not want to see.
Our attention is very selective when it comes to getting information from our environment. We could be looking at everything within our environment and miss changes that occur while looking. According to Rensink, O’Regan and Clark (1997), attention is a key factor, meaning when our attention is focused on the area of change then change can be detected. When we fail to detect change, it can result in change blindness. In support of this idea, Simons and Levin (1998) suggest that change blindness occurs if there is a lack of “precise” visual representation of their surroundings. In other words, a person can be looking at an object and not fully notice a change.
Everyone has a different perception than another, such a different perception that should be taken into account by other people. Whether people are blind or crazy, some people of this world are impaired so their lives are limited. The unknown can be very mind-boggling to these impaired people. Though at the same time there is a strong possibility that there are also even more unknown things to unimpaired people. Plato’s “The Allegory of the Cave” and “Seeing” by Annie Dillard suggest that knowledge and reality are both a matter of perception based on experiences; and as such, great care should be taken by anyone who attempts to redefine the perceptions of another.
Visual Discrimination is “using the sense of sight to notice and compare the features of different items to distinguish one item from another” (NCLD Editorial Team, 2014) http://www.ncld.o...
Each one of us lives in our own unique world of perception. As individuals, we may experience life in an entirely different way through our senses and life experiences. Therefore, perception can be tricky since it is very personal to each one of us. According to the Merriam-Webster online dictionary, perception has three meanings; (1) “the way you think about or understand someone or something,” (2) “the ability to understand or notice something easily,” and, (3) “the way that you notice or understand something using one of your senses” (2014, para. 1). C.S. Lewis said, “What you see and what you hear depends a great deal on where you are standing. It also depends on what sort of person you are” (n.d., para. 11). In other words,
Perception is defined as the process of organizing, interpreting, and selectively extracting sensory information . Visual perception is left to the individual person to make up their own mind. Perceptual organisation occurs when one groups the basic elements of the sensory world into the coherant objects that one perceives. Perception is therefore a process through which the brain makes sense of incoming stimuli.