What can neuropsychologists learn by studying individuals with damaged brains?

mental hospitalOne of the best ways to learn astir(predicate) the normal mathematical operation of the headspring is to translate how it functions when it is handicapd (Rosvold, Mirsky, Sarason, Bransome et al., 1956). This paradigm for investigate in neuroscience involves shadowervass the neural go and performance on cognitive tasks of normal controls to that of patients with outlook footing (for example, Fellows and Farah, 2003). Studies of locate principal abuse put forward abide especially important implications, since the impaired in operation(p) bea is likely to be associated with that place in the point containing the lesion. Though this is just wiz paradigm apply in mapping the functional beas of the brain, other methods involve using and healthy participants and studying the conformation of neural activating during particular(prenominal) tasks knowing to stimulate different cognitive faculties. But by comparing the mathematical operation of h ealthy individuals to patients with brain damage it has been assertable to scar very particular proposition areas of the brain ascendentd on their functional purpose. Purpose of specific areas is either based around sensation and perception, information processing, retentivity or executive director decision-making.This essay bequeath examine some of the most pertinent findings gleaned from studies of brain disgraced patients and elaborate on the avenues for future explore in this context. The come off of literature bequeath proceed in a systematic elbow room evaluating the function of diverse brain areas through examination of the make of lesions in these areas, as rise up as elaborating on the limitations of the methodologies employed.There are legion(predicate) ways in which the brain can be shamed, but the agentive role that seems more important in determining the effects of brain damage rather than how the brain damage occurred is the fixing of the damage. Ev idence for this comes from reviews such as Ommaya and Genarelli (1974) who correlated clinical and experimental observations with the location of lesions in the brain. This essay will now proceed by analysing the effects of brain damage in different functional areas and the neural correlates of these effects. brainiac damage can harbour a diverse range of effects depending on the region that is damaged, including disturbances in perception, attention, shop and executive decision-making (Brewer and Perret, 1971). Prominent in this field of research are studies such as that of Robinson, Kubos, Starr, Rao and Price (1984) who studied patients with stroke lesions in various locations in the brain. Their findings showed a greater incidence of depression in individuals with front tooth lesions on the left rational hemisphere. The inverse was true of right cerebral lesions, with screw lesions leading to more depressed mood. This suggests that the location of lesions has an effect on t he form that mood change takes following a stroke. To generalise that from this, different areas of the brain are differently responsible for feelingal order and the cerebral hemispheres are oppositely arranged with regard to the operation of emotion. This research however was purely correlational, and therefore suggests nonhing of the mechanism behind the effect, and in fact cannot imply cause and effect at all between observations. Also, only depression was taken into account, measured with standard instruments for gauging levels of the disorder. This methodology misses a potential wealth of nuanced information on the subtle temperament changes that surely accompany mood disorders following stroke, qualitative methods could peradventure have reveal more, and future research is needed to investigate other aspects of mood effects of brain damage. Brain damage can also profoundly necessitate memory in various ways as well as affecting mood and demeanour (Graham and Hodges, 19 97).The effects of brain damage on memory are as variable as the forms of memory itself. The a posteriori research into this area has elucidated not only the effects of brain damage but also the processes by which different kinds of memory are encoded, stored and retrieved and the structures principally tortuous. This is possible through deduction based on the pattern of trauma in a particular patient in relation to their specific lesion (Graham and Hodges, 1997). In the case of workings memory, research has shown that even patients with mild brain damage show a tendency towards enhanced activation of circuitry associated with information-processing when tried and true on the selfsame(prenominal) working memory tests as controls (McAllister, Sparling, Flashman, Guerin, Mamourian and Saykin, 2001). This kind of research has elucidated the structures and pathways associated with working memory, but it cannot rule out the possibility that these areas of the brain are involved i n multiple pathways necessary for other cognitive processes. This is perhaps only a fraction of the information which could be extracted by study of working memory circuitry and how it functions in conjunction with the bide of the brain. Although this research has highlighted areas applicable to working memory it says little about the processes involved or how the brain functions as a whole in this function. In addition to working memory, damage in different areas has been shown to affect long-run memory which will now be explored.Research into alienation and Alzheimers disease as well as patients with frontal lobe damage has uncovered information about the encoding and storage of long-term memory (Graham and Hodges, 1997). Graham and Hodges (1997) investigated the role of subcortical structures in the formation of new memories through the study of patients with degradation of hippocampal structures (Alzheimers patients) as compared to those with comparably spared hippocampal st ructures but atrophy in neocortical areas (patients with semantic dementia). Their findings show that patients with spared hippocampal structures had greater recall for recent memory than more impertinent memory, whereas patients with Alzheimers disease showed the opposite pattern. These observations have helped to establish the pathway via which short memory passes into long-term memory, and thus has important implications of our understanding of the storage of memory in the brain. This study does provide strong try out for the proposed conclusion, although the specific mechanisms by which short-term memory is transferred and stored between regions remains mysterious. Indeed, the actual location of long-term memory storage itself remains mysterious. It seems likely then that this process is not as simple as is proposed here. Of course not all stimuli are represented the same way in memory, some are unrestrainedly charged. This essay will now explore how research into brain dama ge has helped the understanding of emotional activation in the brain.Emotional memory and functioning is another area in which study of brain damage can supplement valuable information. It is well known that the amygdaloid nucleus plays a full-size role in the experience of emotion, so it follows that Cahill, Babinsky, Markowitsch and McGaugh (1995) found that memory for emotionally charged stimuli and events was impaired in patients with damage to the amygdala, whereas memory for neutral autobiographic events and experimental stimuli was within the normal range. The benefits of research on brain damaged patients can perhaps best be seen in this area because of the speciality of patients with selective lesions localised in the amygdala (Adolphs, Tranel, Damasio and Damasio, 1994). Although research into the function of the amygdala in healthy participants successfully revealed that it is involved broadly in emotion (for example, LeDoux, 2003) research into the rare cases of loca lised damage to the amygdala (with normal functioning elsewhere) have enabled researchers to add clarity and specificity to this statement. Adolphs et al. (1994) discovered that the amygdala functions with a sociable dimension as well as an emotional one. Specifically, it is essential for the actualisation of emotion (especially fear) in other people, but it is not necessary to fleck individual identity from faces. This shows a clear parcel to the knowledge base from studies of brain damage the constraints were added to the general statement that the amygdala is simply involved in emotion. It would have been difficult to discern this information from examining only the activation patterns in the brain and behavioural functioning of healthy participants, as the unaccompanied shape of the amygdala could not easily be isolated from the rest of the brain without it being removed. Necessarily though, such studies lack a plastered ecological validity because the observations are nat urally limited to such a low number of cases due to the rarity of localised amygdala damage. another(prenominal) important functional area brain damage can influence is cognition and executive decision-making.By studying patients with frontal lobe damage it has been possible to determine the role it plays in cognition, problem-solving and decision-making. In procedures such as the Wisconsin card-sorting test, participants can be accurately assessed for frontal lobe damage based on how well they can sort the cards into categories and their flexibility in doing so with shifty classification criteria (Stuss, Levine, Alexander, Hong, Palumbo, Hamer and Izukawa 2000). This task can even be used to distinguish the location of the damage within the frontal lobe by varying the add up of specificity in external direction. The fact that cognitive functioning can so accurately reflect the location of damage in the brain shows once more the opportunity for mapping brain functions based on dat a placid from patients with impaired functioning in specific areas. This kind of test has particularly good reliability since the test thoroughly assesses cognitive decision-making with the absence of activation in only one very specific area. A reprehension must be that the task is probably quite dissimilar from anything the participants are likely to perform in their daily life it is contrived to be carried out under experimental conditions, and therefore the results may not be as valid as they appear in naturalistic situations. Although the the true with which the test can distinguish the specific location of damage gives it touchstone validity. This concludes the review of research into the influence of brain damage on functional ability and demeanour.This essay has presented research on the effects of damage in various locations within the brain on behaviour, sensation, memory and cognitive processing. The contribution to knowledge of the purpose and integration of various regions in the brain have been discussed, the general conclusion being that it would be difficult to gain the same insight into the specific role of structures and the form of neural pathways without the study of patients with localised brain damage. Other paradigms exist in neuroscience, but studying the pattern of impairment in patients with localised brain damage compared to controls provides perhaps one of the best ways to assess the function and contribution of that particular damaged area. There are of course confounding variables though such as the way the damage occurred, and individual differences in participants.References Adolphs, R., Tranel, D., Damasio, H., & Damasio, A. (1994). Impaired recognition of emotion in facial expressions following bilateral damage to the human amygdala. Nature, 372(6507), 669-672.Brewer, C., & Perrett, L. (1971). Brain Damage due to Alcohol Consumption An Air?encephalographic, Psychometric and electroencephalographic Study. British Journal of Addiction to Alcohol & Other Drugs, 66(3), 170-182.Cahill, L., Babinsky, R., Markowitsch, H. J., & McGaugh, J. L. (1995). The amygdala and emotional memory. Nature, 377(6547), 295-296.Fellows, L. K., & Farah, M. J. (2003). 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