Visual Form Agnosia Essay

Visual agnosia refers to the “…inability to recognize objects that results neither from general intellectual loss nor from a loss of basic sensory abilities,” (Anderson, 2009, p. 32). There are generally two types of visual agnosia: apperceptive agnosia and associative agnosia. Apperceptive agnosia is the inability to recognize or draw simple shapes as they are shown or represented. Associative agnosia is the ability to recognize and copy drawings of simple and complex shapes. However, person with associative agnosia are unable to recognize the complex objects (Anderson, 2009).

The system consists of the eyes where the information is collected, geniculate lateral nucleus and visual cortex. The visual cortex could be subdivided into the primary visual cortex and the striate cortex. This sensory system is located at the back of a brain parts of which are located in both hemispheres. Recent studies obtained a sufficient amount of information in order to construct the two-stream hypothesis, which describes the ventral and dorsal streams. The ventral stream begins at the primary visual cortex and goes to the inferior temporal cortex. Main functional responsibilities of this area include identification of objects and the emergence of the long-term memory the origins of which are placed in this area (Rauschecker, Josef P and Sophie K. Scott 722). Dorsal stream also begins at the primary visual cortex and ends at the posterior parietal cortex. It is mainly responsible for the body part control required in order to manipulate an object. The research shows that these "what" and "why" systems are not directly related, and the damage in one affect the other only to a certain extent. It could be explained by the fact that that input is transformed differently via action and

In a case similar to Graham Young, Peggy Palmer suffers from visual neglect caused by a stroke in the parietal lobes of the brain. Dr. Ramachandran explains that parietal lobes create a three dimensional layout of the world around us, which allows us to navigate our direction. The patient can see, but only on one side or the other, i.e. she only sees half of what is really there. During an experiment where the patient was asked to draw a picture of a daisy from memory, she was only able to draw the right half of the daisy.

Over the past few decades, enhancements in the visual fields have greatly improved, giving weight on the importance of visual material in text. Something that is more visually stimulating can usually make a text more convincing or credible. The term “seeing is believing” proves this fact. As humans, we tend to believe something if we can actually see it, which is why Jay David Bolter has referred to this phenomenon of the changed role of text and graphics as the “visual culture” in his book Writing Space. “Mere words no longer seemed adequate; they had to share their space with images.” (Bolter, 69).

Dr. P, a musician and teacher who had developed visual agnosia, had difficulty processing what he sees, especially faces, he could only identify them by features which he remembered. He only completed tasks if he was singing, if interrupted, he could no longer remember what he was doing nor complete it. Sacks diagnosed Dr. P with prosopagnosia, the inability to identify

Neurons' firing while observing an action can be helpful in planning one's actions, as the consequences of those actions can also be observed.

The frontal lobe is responsible for decision making, processing (like planning), and speech fluency. In our exhibit, the frontal lobe is represented by stimulating activities including tongue twisters and a “chose your

In Oliver Sacks’ The Man Who Mistook His Wife for a Hat, he denotes a “deficit is an impairment or incapacity of neurological function; such as loss of speech, loss of language, loss of memory, loss of vision loss of dexterity, or loss of identity” (Sacks, 1985). The specific neurological disorder that is highlighted in chapter one is Visual Agnosia, which is a deficit associated with poor primary visual processing that affects shape perception, figures, object, face and letter recognition (Serino, et al., 2014). Other subtypes of visual agnosia that also seemed to fit the descriptions that Sacks shared is prosopagnosia, which is the inability to recognize human faces (Shah, 2016), and pantomime agnosia, characterized as the inability to understand gestures (Gonzalez, Mack, & Heilman, K., 1986).

Unit 8 Answer: Before answering this question, I will first define conscious awareness and neural circuit; conscious awareness is known as the “individual awareness of your unique thoughts, memories, feelings, sensations and environment” (Cherry, n.d.) while neural circuits are neural ensembles that process specific kinds of information such as visual or sensiorimotor input (Purves, 2001). As we have learned in previous chapters, neural mechanisms of conscious visual perception (the ventral stream) are not necessarily the same as those that mediate the visual control of behaviour (the dorsal stream). There are typically two hypotheses of how neural processing occurs consciously and unconsciously: response-chunking hypothesis and shifting control

c. One study showed a 37% reduction of the brain’s activity in the parietal lobe that processes cognitive, memory, information regarding the driving task, sense of direction and “spatial sense” as well as the occipital lobe that processes the visual information (Aker, 2011).

The findings of Oliver Slack along with Vuilleumier & Schwartz reveal further insight into the psychological impairment known as unilateral neglect. This condition commonly occurs in individuals that have survived strokes. Unilateral neglect is the phenomenon in which an individual is unable to attend to one side of space within their environment. One’s side of space refers to only experiencing either the left or right side of possible incoming stimuli depending on physical orientation. Looking at the stimuli that is affected, individuals with this condition are unable to hear sounds or visually see the space that is ignored. Think of it as holding a piece of paper perpendicular to one’s face, aligned in the middle with the nose, and only being able to attend to either the left or right side of incoming stimuli. The range of space that is unnoticed depends on the individual and the severity

The phenomenon of blindsight has far reaching implications regarding consciousness, awareness and the "I" function. These studies demonstrate that receiving and interpreting visual inputs is independent of our awareness of that input. Does this imply that there is a separate mechanism of "consciousness" which can be disengaged from our senses? Marcel proposes that this loss of visual consciousness results from the

Appreceptive visual agnosia: display the ability to see contours and outline when Shown an object but they experience difficulty if asked to categorise objects.It is also known as visual space agnosia, which is a condition in which a person fails to recognize objects due to functional impairment of the occipito-temporal visual areas of the brain, while other visual functions are intact such as: colour vision, brightness

Agnosia is defined as the inability to recognize objects through the processing of sensory information, which means there is no deficit in semantic memory or problems with naming objects. An individual suffering from agnosia still possesses all the relevant semantic information tied to a precept, but they cannot recognize the precept when it is presented to them and therefore trigger the recall of said information. There are many types of agnosia, but this essay will focus on visual object agnosia and prosopagnosia. The former is the inability to recognise objects: patients suffering from visual object agnosia do not have impaired vision, and in some cases can even copy the object they are seeing (patient H.J.A., Humphreys & Riddoch, 1987) or draw it from memory (patient D.F., Milner & Goodale, 1992), but are unable to recognize it when they see it. In the latter, prosopagnosia, patients cannot recognise faces of familiar individuals, and have to rely on other characteristics such as their voice or clothing to recognize them. Patients suffering from prosopagnosia can either acquire it through a lesion in relevant brain areas (acquired prosopagnosia) or for less understood reasons have it from birth, in which case it is termed developmental prosopagnosia. The study of patients with agnosia is integral to the field of visual recognition, as the specifics of their deficits can provide great insight into the ways our brain processes information; for example, the location of

The Visual Art is an important part for students to learn, especially students in the early childhood education because it develops their self-expression, imagination, creativity, confidence and observation skills. Also, the Visual Art is implemented in the Australian Curriculum and Early Years Learning Framework. Hence, this documentation focuses on conducting an authentic art learning experience through observing and exploring with leaves and colours for an early childhood aged child called Jenny. This activity also provides opportunities for the child to learn about colour through personal experience rather than through teachers’ teaching or quizzing (Pelo, 2007). Therefore, the child will work through different processes to investigate colours based on her prior knowledge. In other words, the child will use different materials, such as leaves, colours and brushes, techniques and processes to explore visual conventions (ACAVAM111)(ACARA, 2014) and paint leaves by using the mixing colours.