Prosopagnosia: Reasons and Effects - Essay Example

? Prosopagnosia: Reasons and Effects Social interaction plays a very important role in human communities; and forms the basis for the development of healthy relationships. Historically, knowing friendly faces from unknown or unfriendly ones was a necessary ability for early man’s survival, and the ability is still deemed very important when considering personal safety. Besides this, the ability to recognize familiar people plays a very valuable role in the development of relationships and as an aid to healthy and reciprocal social interaction. Thus, when someone finds it difficult to recognize people, it can create a number of problems in social interaction and in perusing relationships. Introduction Facial recognition is an ability that most individuals take for granted, but has been found to be quite complex (Diamond & Cary, 1986) and associated with different temporal, occipital, and frontal brain areas, and particularly the fusiform gyrus in the visual cortex. Presented featured are analyzed, relationships are drawn between the various component parts and then combined to form meaningful bits of information that can then be compared across information that has been previously stored in memory. Both, first and second order relational information – information about the relationships shared by the features of the face as well as information about the faces experienced and the abstractions formed on the basis of the same – are necessary for recognizing a face (Diamond & Cary, 1986). It has been found that faces are stored in memory as holistic units, and it is more difficult for most people to recognize a partial face as compared to a complete one. Tarr and Cheng (2003) have outlined the distinctiveness of face recognition procedures, including presenting evidence for the assumption that information about faces seems to come in at the individual level entry point as against the basic level entry point for objects. This could explain why faces are differentiated as whole units or composites and not on the basis of particular features. Rakover and Cahlon (2001) have discussed the evidence for the role of long term memory in face recognition. They have outlined the importance of structural encoding, the view centred description and the expression independent description in face recognition. Retrieval of information processes also play an important role, as described by Robinson-Riegler, & Robinson-Riegler (2008). Prosopagnosia Prosopagnosia is a condition that describes an individual’s inability to recognize faces, is composed of a set of independent symptoms and is seen to exist at varying levels in different persons. The name comes from the Greek words for ‘face’ and ‘not knowing’. These individuals encounter difficulty in recognizing faces, of making sense of the presented faces. In extreme cases, they are unable to recognize the most significant individuals in their lives, and even themselves. These individuals are still able to use other cues to recognize people; and those with mild symptoms can often conduct themselves in society with little difficulty. It has become evident that damage to the fusiform gyrus is implicated in cases where the condition is acquired after some form of injury to the brain, and it was initially believed that most cases of Prosopagnosia are a result of similar injuries. Over the years, though, it has become evident that there is also a genetic component in acquiring Prosopagnosia (Gruter, Gruter, & Carbon, 2008; Wilmer et al, 2010); and that a number of individual seem to have varying symptoms since birth (Wilmer et al, 2010). Some individual with Prosopagnosia show other forms of perception and retrieval failure; but more and more data is making it evident that Prosopagnosia is distinct from other forms of agnosia (Wilmer et al, 2010); and research on Prosopagnosia has been critical in developing an understanding for a distinct face recognition system in human cognition. The validity of this hypothesis has also been verified through the use of fMRI and EEG measures which have implicated the fusiform gurus in face recognition (Gruter, Gruter, & Carbon, 2008). Research has confirmed the genetic basis of Prosopagnosia; and the present understanding is that nearly 2.5% of the population is likely to show some aspects of the symptoms. Not all these individuals show the same disability – with qualitative and quantitative differences in the manifestations of these symptoms. Given the complexity of the face recognition model; it is understandable that Prosopagnosia is not a unitary condition; and can manifest itself in a variety of forms depending on which cognitive function suffers damage. It was also been postulated that almost 10% of the population may suffer very mild symptoms of Prosopagnosia that manifest themselves only on close examination. Congenital Prosopagnosia (Wilmer et al, 2010) and Prosopagnosia caused through injuries sustained in early childhood are often clubbed under Developmental Prosopagnosia. Apperceptive Prosopagnosia is a type of Prosopagnosia in which the individual is unable to distinguish between face related stimuli and is also unable to distinguish attributes of individuals on the basis of facial information (Rakover & Cahlon, 2001). Their processing of other information is relatively un-impaired, though, and these individuals are able to identify others on the basis of other cues like hair, voice and gait. It has been proposed that Apperceptive Prosopagnosia occurs due to some damage of deficiency early on in the face perception system, like at the point of structural encoding. Another form of Prosopagnosia is Associative Prosopagnosia. Associative Prosopagnosia is a condition that manifests in an inability to make connections between facial information and other information. Although these individuals are able to distinguish between faces, and are able to determine gender and age from the presented stimuli; they are unable to reproduce this information at a later point (Rakover & Cahlon, 2001). They are also unable to associate it with other information like names and occupations; although such associations are made on the basis of the person’s voice, gait, or specific physical feature. It is thus believed that since these individuals are able to make sense of faces, the perception processes are functional. On the other hand, the processes like the expression independent description and use of second order relational information are hampered. Although it is evident that a number of individuals who have Prosopagnosia are unable to recognize even the most familiar faces; it has been determined that it does not affect the emotional response system (Rakover & Cahlon, 2001). A number of individuals who are unable to recognize faces nevertheless exhibit emotional responses to familiar faces as against unfamiliar faces when tested for skin conduction (Bauer, 1984). It may thus be postulated that these individuals are not inhibited in the process of face recognition; but in the retrieval process or in the use of the view centred description. This is on the basis that an emotional response would assume some form of encoding of the face (Bauer, 1984; Rakover & Cahlon, 2001); but the inability to consciously recognize it underlines the problems in recognition. Social and emotional consequences of Prosopagnosia Individuals with Prosopagnosia that is the result of an accident are most likely to realize the extent of the problem. This is because they would be able to compare previous experiences with present ones (Rakover & Cahlon, 2001). Also, since they would be assessed for damage by the doctors that treated their injury, they would continue to receive feedback for their condition from the said doctors and would also be asked to become involved in determining the extent of the problem. Having this knowledge would equip the individual and help him / her anticipate difficulties and prepare for the same. At the same time, these individual are more likely to experience frustration due to their keen understanding of their disability. On the other hand, individuals with congenital Prosopagnosia are less likely to realize that their experiences are particularly different from those of other people. They are likely to use other cues to recognition from a young age (Rakover & Cahlon, 2001), and thus those with mild to moderate symptoms may appear relatively well adjusted, and may not realize they have a problem until well into adulthood. Those with severe symptoms are more likely to be identified at an early age, and with some training, may be able to use alternative cues to cope with most social situations. Individuals with Prosopagnosia are likely to face a number of difficulties in their personal and social lives (Sellers, 2010); and are likely to have fewer friends and acquaintances. Their inability to remember people’s faces may result in them not being able to follow socially accepted customs like greeting acquaintances on meeting would make it seem that they are ignoring the acquaintance; causing social friction. This would lead to lesser likelihood of forming deep and meaningful relationships. Since these individuals have difficulty in recognizing people, they are likely to experience embarrassing mis-recognitions (Sellers, 2010) and such experiences at a young age are likely to make them shy and stand-offish. Shyness is also a result of not being able to recognize people; and thus, feeling like one is surrounded by strangers. Friction with family members is also possible for those who have particularly severe symptoms and are unable to recognize those nearest to them. This combination of frustration and social friction is likely to cause individuals with Prosopagnosia to feel cut-off from the rest of the world, and to experience difficulty in social interaction even at the most basic level. Conclusion On the basis of this information, it may be possible to hypothesize that individuals experiencing mild to moderate symptoms of Prosopagnosia may be sometimes diffident, and a little shy; but do find ways to conduct social interactions relatively normally. They are likely to worry about experiencing embarrassing situations; and to second guess themselves about acquaintances, and may need alternate cues to recognition (Rakover & Cahlon, 2001). But on a whole, they may not experience significant difficulties in social situations on a daily basis. Those individuals experiencing more severe symptoms on the other hand, are likely to be more in need of help, and may retreat from social situations. They are more likely to be loners since they have difficulty in recognizing people, and thus, may not interact with them. These individuals may need help in adjusting to their symptoms, and may also experience emotional distress (Sellers, 2010) as a result of the stress they experience on a daily basis. References Bauer, R.M., 1984. Autonomic recognition of names and faces in prosopagnosia: a neuropsychological application of the Guilty Knowledge Test. Neuropsychologia.  22 (4), p. 457–69. Diamond, R., and Carey, S. 1986.Why faces are and are not special: An effect of expertise.  Journal of Experimental Psychology: 115, p. 107 -117. Gruter, T., Gruter, M., and Carbon, C.C., 2008. Neural and genetic foundations of face recognition and prosopagnosia. Journal of Neuropsychology. 2 (1). p. 79 – 87.  doi: 10.1348/174866407X231001. PMID 19334306. Rakover, S., and Cahlon, B., 2001. Face recognition: cognitive and computational processes. NY: John Benjamins Publishing Company. Robinson-Riegler, G., and Robinson-Riegler, B., 2008. Cognitive psychology: Applying the science of the mind (2nd ed.). Boston , MA : Pearson/Allyn and Bacon. Sellers, H., 2010. You don’t look like anyone I know: A true story of family, face blindness, and forgiveness. Riverhead Books. Tarr, M. J., and Cheng, Y. D., 2003. Learning to see faces and objects. Trends in Cognitive Science, 7, p. 23-30. Wilmer, J.B., Germine, L., Chabris, C.F., Chatterjee, G., Williams, M., Loken, E., Nakayama, K., and Duchaine, B., 2010. Human face recognition ability is specific and highly heritable. PNAS. Published online before print February 22, 2010. doi:10.1073/pnas.0913053107 Read More