The notion of visual information processing is an effort to understand the complex integration of an organism’s internal functioning and his apparent behavior. Many researchers have laid the concept of the interrelation of brain’s neuronal activity and our conscious visual experience. Whereas the inaugural researchers in the field of cognitive psychology have made efforts to outline the anatomy and physiology of human brain’s visual areas’ response to external stimuli, many recent researchers have started to imply more on decoding the neural code of visual perception and the concept of hierarchies of visual computations. This paper will focus on the processing of visual information in the occipital cortex, two medical conditions that effect the visual information processing and the latest trends that have aid in the better understanding of this phenomenon.
Human brain is a complex matter that has designated its several regions for interpretations of specific stimuli, which may overlap with each other sometimes. In regard of the visionary stimulus, initially it sits on the retina and axons exiting the retina that make up the optic nerve, take this information to the visual cortex i.e. the occipital lobe of the brain. Two relays for the visual information are the thalamus (the primary relay) and the superior colliculus (helps in the movement of the gaze). Occipital lobe, which not only is responsible for perceiving but also for analyzing the external stimulus, is divided into many hierarchal sub regions each contributing to the processing of the simple to complex visual inputs in a descending manner. These areas decipher the ‘What’ and ‘Where’ information from the external stimulus. The top area of the ‘What’ region tells us the type of external stimulus like face or any object in particular. The top area of ‘Where’ region integrates the saccadic eye movement that helps us with the placement of our gaze on any object.
Visual information processing skills can be divided into many subareas. They include visual spatial skills, which is the ability to judge the environment in context to oneself, visual analysis skills, which is the ability to detect, recollect and manipulate information from the already stored visual memory, and the visual motor skills, also known as the ‘hand-eye coordination’, is the synergistic movement of the hands in accordance to the visual stimulus. Many medical conditions can affect the visual processing of the brain disrupting it at any level between the eyes and the brain. Two of these conditions are the visual processing disorder or dyslexia and the age related macular degeneration affecting figure-ground discrimination.
Dyslexia is the disorder of the brain’s area called the lateral and ventral geniculate nuclei of thalamus, that makes it hard for the person to read, write and spell. This condition has varying degrees of difficulties ranging from inability to interpret and analyze moving visual stimulus and differentiation of simple phonetics. Visual information is relayed at the lateral geniculate nucleus of thalamus, specifically the Magnocellular and the Parvocellular cells. In dyslexics, either these cells do not recognize their division of labor or they overlap in function, therefore leading to difficulties in visual motion detection. Neuropsychotherapy, phonetic instructions, auditory stimulus and proper nutrition have showed positive results in coping with dyslexia throughout the life.
Age related macular degeneration (AMD) can lead to disruption in figure-ground discrimination of the adult. It results in irreversible degenerative changes in the central part of the retina called ‘macula’ leading to changes in perception of visual stimulus. Figure-ground discrimination is the ability to differentiate multiple objects in relation to the foreground and background stimulus and as the age progresses their ability to discriminate the object from their fore/background decreases. Researches have shown that a white space around the objects can help in improving the contrast between different objects hence aiding in geriatric population’s visual rehabilitation.
Many researchers in the current time have yielded new ways to study the concept of visual information processing. Similarly, Sterzer et al. present a critical review for Continuous Flash Suppressing (CFS) technique and the present knowledge about the science of how the interocularly suppressed information is processed in the brain and the controversies relating to it. When two high contrasting images competing for dominance are presented to the eyes, one of the image is suppressed in one eye unconsciously for a few minutes. This phenomenon helps in understanding the visual processing of either social, emotional or materialistic stimulus when there is no conscious awareness. On the other hand, this technique had its drawbacks at the same time such as the disappearing image in the binocular rivalry was documented to reappear on and off in between leading to false positive findings or the suppression of the stimulus was too deep negating the stimulus completely resulting in false negative results(Aboudib, Gripon, & Coppin, 2016).
Future studies should avoid subjective documentation of the suppressing image and the examiner should hold threshold of the stimulus suppression hence altering it accordingly. Another technique that has emerged from the (CFS) is the “breaking-CFS” that measures the time for how much the suppressed stimulus remains in the state of unawareness. Although this technique is still debatable, neuroimaging can help solve this by conjoining the neural responses to the initially suppressed stimulus and the time taken by the stimulus to reappear. (Sterzer, Stein, Ludwig, Rothkirch, & Hesselmann, 2014)
In recent times, many researchers under the light of visual information processing, are aiming at combining the science of the ventral stream in order to achieve better understanding of machine learning algorithms for artificial intelligence. This research paper focuses on providing a skeletal framework for visual information acquisition by providing two prodigies in order to achieve the aforementioned goal, and that are cortical magnification and selective visual attention. The former helps in administering the saccadic eye movements for stable gaze movements while the latter being the primary part of the visual system, helps in decreasing the amount of visual stimulus entering the eye. This framework can be administered flawlessly without the spatial disruption and the difficulty of adjusting the size of the image.
Moreover, it can helps in understanding the interrelation of human eye’s distance to an object for a given visual task and decreases the amount of visual input received by the brain. In the coming times, this research paper offers to be used as the base for object recognition processors that are attention-based; also, other commonly used architectures processing vision can use this framework in a more effecient way.