Case history
At first, it is important to discuss the history of this case as well as the symptoms displayed by the patient. Dr. P. was a music teacher who had difficulties in recognizing the faces of students and colleagues; nevertheless, he could easily recognize them by their voices. Thus, one can suppose that this person could not memorize visual information. However, this individual exhibited more disturbing symptoms. In particular, he could mistake water hydrants for the heads of children (Sacks, 1999, p. 9).
In the beginning, he thought that his eyesight had been impaired in some way. So, he decided to seek the assistance of an ophthalmologist. Nevertheless, the examination revealed that there had been no problem with Mr. P.’s eyes. Moreover, it became apparent that his difficulties could not be resolved by an ophthalmologist. The problem is that this patient could confuse objects that had similar shapes.
For instance, Mr. P. could confuse a shoe and a foot (Sacks, 1998, p. 11). Apart from that, this individual could not interpret the meaning of an object. For instance, when looking at a glove, he could depict as a “continuous surface” that was “infolded on itself”, but he could not immediately name it (Sacks, 1999, p. 16). One should also keep in mind that Dr. P knew the word glove and its meaning. Furthermore, while looking at a rose, he could name different attributes of this flower. However, he could identify its name, only when he could smell it.
At the same time, Dr. P. did not have any problems in recognizing geometrical figures or naming different cards. Moreover, he could visualize schematic objects. For instance, he could play chess without looking at the board (Sachs, 1999, p. 17). Nevertheless, he could no longer read musical notation (Sacks, 1999, p. 13). Overall, these details are essential for assessing the problems faced by the patient. One should note that during the later years, Dr. P.’s disease only intensified, but he was able to teach music during his entire life.
Neuroanatomy
In this case, one cannot localize the origins of Dr. P.’s problems only to one hemisphere because different parts of the brain process and interpret visual signals. Much attention should be paid to the cerebrum because it includes various components that are essential for the retention and analysis of visual information.
It is possible to assume that temporal lobe is affected because this area is critical for memorizing visual information such as people’s faces (Freberg, 2009, p. 44). Apart from that, a physician should examine the functioning of the occipital lobe (Freberg, 2009, p. 44). It is necessary for analyzing and interpreting visual signals. Moreover, fusiform face area might have been affected because this part of the brain also plays a significant role in facial recognition (Goldstein, 2009, p. 96).
So, it is vital to apply various techniques that can be useful for identifying the potential causes of Dr. P’s disease. This disorder can be caused by various problems such as brain injuries, tumors and temporal lobe infarctions (Moore, 2008, p. 278). Each of them can pose considerable threats to the life of a person.
One may also need to search for lesions that can lead to the loss of visual perception; moreover, they can deprive people of their ability to interpret visual signals. Overall, it is possible to suppose that the visual cortex of Dr. P.’s brain has been injured in some way. So, one should apply different neuroimaging methods that can highlight potential damages in this part of the brain.
Assessment of the patient’s state
In this case, I will need to administer a series of tests to evaluate the way in which this patient perceives images. In particular, Dr. P should perform the tasks requiring a person to name various objects. Much attention should be paid to the objects that have similar shapes; it is possible to consider such pairs as a hand and a glove, or a foot and a shoe. Additionally, I will need to give the so-called “unusual view tests” (Parkin, 1996, p. 43).
They are aimed at showing if people can understand that an object can be positioned in different ways (Parkin, 1996, p. 43). Overall, these activities are helpful for identifying possible deficits that affect the life of this patient. Furthermore, the patient should do different memory tests that can show how people can memorize different types of information. Finally, it is necessary to show if this individual can identify different objects by touch.
Overall, this examination should determine if other cognitive processes have been impaired in any way. Furthermore, one should ask this patient if he had recently experienced dizziness or severe headaches since they can be the symptoms of a tumor that may undermine visual perception (Moore, 2008). Overall, these steps are helpful for identifying the brain areas that can be endangered due to some reasons.
Nevertheless, it is vital to employ various neuroimaging techniques that can be useful for identifying the problems in the functioning of the brain. In particular, one should apply magnetic resonance imaging that can be regarded as the structural method. This approach is valuable for diagnosing brain tumors that often lead the problems with the recognition of visual images. Apart from that, it is possible to consider the use of the computed tomography.
This structural neuroimaging technique can show if a person has brain ischemia that causes temporal lobe infarctions. As it has been before, such infarctions can impair the ability to interpret visual signals. Furthermore, one should consider the use of neuro-vascular angiography since this method is useful for finding lesions that can also result in the inability to perceive images.
Overall, the information derived in these ways can be helpful for protecting a patient from further risks. Moreover, this discussion shows that prior to selecting a neuroimaging method, one should consider potential causes of this disorder and examine a certain brain area.
Additionally, it is possible to apply positron emission tomography or PET. It is a functional method of neuroimaging. This approach is useful for showing how different areas of the brain work at the time when a person performs a mental task such as recognition of visual patterns.
In this case, it is necessary to focus on the role of fusiform face area that plays an important role in the recognition of faces. In turn, PET can demonstrate if there are certain abnormities in the functioning of this part of the brain. In particular, it can indicate at lesions that block the activation of the occipital lobe and fusiform face areas.
Moreover, one can employ functional MRI. This functional neuroimaging method is useful because it helps to identify smaller lesions that can lead to this disorder. As a rule, they cannot be found with the help of structural neuroimaging methods. Additionally, they can show what areas of the brain are activated when a patient is engaged in cognitive activities such as identifying distinctions between images. Thus, these tools can help the physician to gain deep insight into the problems encountered by the patient.
Neural systems and diagnosis
The details included in this case study suggest that the visual cortex of Dr. P. brain is affected. It consists of several components such as primary and extrastriate cortexes. One can consider the model according to this cortex divides visual information into dorsal and ventral streams (Goldstein, 2009, p. 89).
The dorsal stream includes data about the movement of objects and their location relative to one another. In contrast, the ventral stream contains information that is necessary for the identification of an object. Dr. P. did have any difficulties in estimating distances between objects. So, one should consider problems with the ventral stream. The ventral stream is dependent on those parts of the brain that store memories (Goldstein, 2009).
For instance, it strongly relies on the temporal lobe. It is one of the details that should not be overlooked because Dr. P. cannot recollect the faces of other people. Overall, the hypothesis about two streams received considerable support from experimental studies (Goldstein, 2009). Moreover, this model is helpful for explaining Dr. P.’s problems.
Under such circumstances, symptoms may not be sufficient for identifying the area that is affected. It is possible that a single lesion can lead to different visual impairments. It is one of the challenges that should be a considered a person who needs to give a diagnosis.
Still, one can argue that Dr. P. suffers from the disease that is known as prosopagnosia; this disorder can be described as the inability to recognize faces (Revlin, 2012, p. 112; Yantis, 2001). Apart from that, one can assume that he struggles with such as a disorder as dyslexia or the failure to recognize written symbols (Revlin, 2012, p. 112). At the point when Dr. P. sought medical assistance, he was no longer able to read musical notation. However, it is not clear if he retained his literacy skills. This issue has not been discussed in this case study.
However, there are other symptoms that should be taken into account. It is vital to focus on the inability to interpret the meaning of symbols. So, in this case, it is possible to speak about the so-called visual agnosia because it incorporates a broad range of problems related to the recognition of images (Farah, 2004).
In this case, one should focus on the category-specific agnosia. It means that a person cannot differentiate classes of objects. For instance, such people cannot see the distinctions between living beings and inanimate objects.
This description applies to Dr. P. who may confuse water hydrants and children’s heads. Apart from that, this individual cannot associate physical attributes of an object and its function. This argument is also relevant to the patient because he can see the attributes of a glove without understanding how it should be used. Thus, physicians should help this person overcome the symptoms of visual agnosia.
Cognitive systems
One should bear in mind that visual agnosia is often accompanied by various cognitive disabilities. However, Dr. P.’s case illustrates that this disorder can exist independently.
Judging from the available description, the patient did not have any verbal impairment that could affect his communication with other people. Furthermore, this person retained his motor functions. Moreover, he remained a good musician. Overall, this individual did not display many of the symptoms that one can expect in such situations. It is one of the reasons why this case is so remarkable.
Nevertheless, one should concentrate on the potential memory deficits that can exacerbate his visual agnosia. If his temporal lobe is damaged in some way, Dr. P. may not be able to retain visual memories. It is one of the reasons why he could not memorize the faces of his students. Furthermore, it may be difficult for him to recollect the meaning of symbols such as the signs of musical notation or even letters.
Very often, there is no effective treatment for visual agnosia, especially if this disease is caused by lesions. Under the circumstances, the task of a therapist is to help a person adjust to this disorder. If other cognitive processes are not impaired, this goal can be achieved. For instance, a patient may be trained to apply different senses to identify different objects.
Overall, this case illustrates the complexity of visual disorders that take their origins in the malfunctioning of different brain areas. The main problem is that the origins of such illnesses can be very difficult to pinpoint. Additionally, it is necessary to administer various tests that are critical for identifying potential deficiencies affecting the life of a person.
Reference List
Farah, M. (2004). Visual Agnosia. New York, NY: MIT Press.
Freberg, L. (2009). Discovering Biological Psychology. New York, NY: Cengage Learning.
Goldstein, E. (2009). Sensation and Perception. Boston, MA: Cengage Learning.
Moore, D. (2008). Textbook of Clinical Neuropsychiatry. New York, NY: CRC Press.
Parkin, A. (1996). Explorations in Cognitive Neuropsychology. New York, NY: Psychology Press.
Revlin, R. (2012). Cognition: Theory and Practice. New York, NY: Palgrave Macmillan.
Sacks, O. (1998). The Man Who Mistook His Wife For A Hat: And Other Clinical Tales. New York, NY: Simon and Schuster.
Yantis, S. (2001). Visual Perception: Essential Readings, New York, NY: Psychology Press.