NOTE: Free essay sample provided on this page should be used for references or sample purposes only. The sample essay is available to anyone, so any direct quoting without mentioning the source will be considered plagiarism by schools, colleges and universities that use plagiarism detection software. To get a completely brand-new, plagiarism-free essay, please use our essay writing service.
One click instant price quote
Neuropsychology studies the relation between brain function and behavior or human behavior as based on the function of human brain. Although the term itself is relatively new (it dates from the 20 th century), the major ideas of the field covered by it have a rather long history. Its current profile is determined mostly by the brain hypothesis (the brain is the source of behavior) and neuron hypothesis (the unit of brain structure and function is the neuron). A general overview of issues brings up the major questions confronted by a neuro psychologist. While a basic knowledge of such issues as outlined below is essential to conducting valid and reliable assessments and conclusions, this knowledge can only be obtained by reading many articles scattered throughout the literature. The issues of generalization vs localization of function has considerable foundation since the beginning of the study of brain behavior relationships.
While the basic orientation of neuropsychology is to assume localization of function, a strict localization of function view is not supported. I have included my outlines of articles by Chapman & Wolf to present the generalist view. In addition to the above approaches, the neuro psychologist should be familiar with the connectionist ic and hierarchical systems approaches and the question of stability vs plasticity. Other issues are outlined below. The key idea in the study of neuropsychology is functional localization. To understand this concept, it helps to look back in history about one hundred years, to a time when phrenologists roamed the land.
Phrenology was the "science" of studying the bumps on a person's head and, by those bumps, predicting the skills, proclivities, and personality of that person -- a practice not unlike palm reading. Phrenologists believed that the brain was divided into distinct parts, each of which controlled some aspect of a person's intellect or personality. Furthermore, they believed that if a person had an excess or a dearth of some trait, the anatomical area representing that trait would be appropriately large or small. Phrenologists developed a detailed map of the brain, with portions labeled "greed, "sloth, "trustworthiness, " and so forth, and used this map to determine what a particular person's bumps signified. The brain is divided into distinct parts, each of which controls some aspect of a person's intellect or personality. However, the size of these parts has no discernable impact on personality, and you cannot feel them as bumps on the skull, so their "science" has no real worth.
Only their idea of functional localization remains: that each function of the brain is localized into one or more physical areas. Neurons tend to cluster according to their function, so that we can say, "this area in the front of the brain helps us plan, " and "this area in the center of the brain directs our movements. " The areas are not isolated, however; the brain relies on communication among its parts, and almost all functions that it carries out are multi-step, requiring processing efforts by many areas of the brain. The anatomy of the brain is complex, but it consists basically of a few large parts divided functionally into many increasingly smaller sections. The large parts are the hemispheres and the lobes. For simplicity of organization, and somewhat on the basis of functionality, the cortex of the brain is divided into four lobes along the lines of the major lumps and creases in the brain.
The four lobes, pictured below, are the frontal, temporal, parental, and occipital. Each lobe does not carry out a single function, but rather contains smaller structures that have their own jobs to do. In some cases, as in the case of the frontal lobe, we will not discriminate between these structures, but rather will pretend that the lobe is a unified whole; in others, as in the case of the temporal lobe, we will only look at the smaller structures and their separate functions. Overall, we will study the function of each major structure in the brain as it applies to neuropsychology. One way to ascertain the function of a certain part of the brain is to give brain-damaged subjects a task that requires a particular skill. If the subjects can perform the task well, we know that the damaged area is not responsible for that skill.
On the other hand, if they fail the task while non-damaged subjects succeed, we know that the damaged area must play some role in mediating the missing skill. Once their validity has been established, we can use these neuropsychological tests to find out how well a certain part of the brain is functioning. In research, brain damage usually stems from one of two causes: organic brain damage or ablation. Organic damage occurs when part of the brain is knocked out by some natural event, such as a stroke or an accident. This is the most ethically sound method of research, since the researchers do not cause any damage to the subjects.
However, organic damage is usually not clean-cut, and it is often not clear which parts of the brain have been truly knocked out. A patient might appear to have damage to the frontal lobe, but the damage might leak over into the temporal lobe as well, or enough of the frontal area might be left intact to preserve its function. Because of these constraints, some researchers prefer to create the damage themselves by ablating a certain area of the brain. Ablation can be performed by administering anything that will kill cells within a certain radius. One preferred method is chemical ablation, in which a toxic chemical is leaked through a thin tube into the area to be damaged.
Ablations are much more clean-cut than organic damage, but, due to obvious ethical concerns, they cannot be performed on humans. Instead, researchers often ablate the brains of animals. Unfortunately, animals' brains are somewhat different from our own, so it is difficult to say whether results from experiments with animals would also hold true for humans. Another way that researchers can study the functions of specific areas of the brain is by taking pictures of it. These techniques are minimally invasive, yet can still provide anatomically detailed information. Functional magnetic resonance imaging is a powerful new technique that allows scientists to watch the brain at work by measuring oxygenated blood flow using a giant magnet.
Using this technology, scientists can watch the brain at work and see which areas "light up" when people perform particular tasks. A person lies flat in a tube surrounded by a giant magnet, which takes many pictures of their brain each second. As he or she performs a particular task, for example, a language-based task such as naming pictures, blood flows to the active portions of the brain to provide them with energy to work. Thus, scientists can tell which areas are active by watching the patterns of blood flow.
In the above example, the language-processing area of the brain would need increase blood flow to perform the task, and this increase would show up on the scan as more brightly colored area. Scientists could then conclude that this brightly-colored area must be the area involved in processing language. Unfortunately, using for research is currently very expensive, due to the high cost for equipment to take measurements and analyze data. Neuropsychology, broadly defined, is the application of psychological principles to the study and understanding of neurological underpinnings of human behavior. The neuropsychology of epilepsy is a subspecialty devoted to the understanding of disturbed brain behavior relationships and treatment of cognitive and behavioral symptoms which accompany seizure disorders. Most practitioners of neuropsychology hold advanced degrees in clinical psychology.
This is supplemented with specialized training in neuropsychology at the postdoctoral level, including intensive didactic and applied clinical experiences. The integration of knowledge from a multidisciplinary background results in a unique understanding of the cognitive, social and psychological problems facing patients with epilepsy. The neuropsychological examination of patients with epilepsy involves objective assessment of various cognitive and affective domains. There is no single instrument or battery of tests which is considered ideal for such an assessment, although several have been proposed. Many neuropsychologist's prefer a combination of individual tests that assess the relevant abilities. These include measures of motor speed and dexterity, visual perception, visual-motor integration, speech and language processing, verbal expressive ability, verbal and visual memory, intelligence, executive functions, personality, and emotional and psychosocial functioning.
As one might imagine, a comprehensive neuropsychological examination is time and labor intensive for the subject and clinician. However, the results provide valuable information about the overall status of the patient and facilitate treatment. Functional status as barometer of disease severity and progression For some patients with epilepsy, seizures result in failure to develop important social and vocational skills, while others suffer from the loss of previously acquired skills. Deficits may be related to impaired neurological function, or may be the result of psychological and social factors such as low self-esteem or stigmatization of the individual with seizures. The difficulties faced by a patient with chronic epilepsy develop over time, often in concordance with the evolution of the seizure disorder. Neuropsychological examination provides an objective index of patient functioning, which is used to document changes in status and modify treatment strategies accordingly.
Cognitive deficits such as learning disabilities, attention disorders, and developmental language disorders may appear in children with epilepsy. As the patient matures into adolescence and the seizure disorder evolves, deficits in memory and executive functions (e. g. , organization, self-monitoring) may become more prominent, impacting on academic achievement and vocational preparation. Also in adolescence, psychosocial deficits appear. Poor self-esteem and fewer relationships with peers are common in adolescents with epilepsy. These factors often interact with treatment variables to produce a complex symptom picture in any given individual.
Determination of the relative contribution of medication, substrate, and emotional / psychosocial effects permits more effective allocation of effort in treatment. Early assessment facilitates identification of the exact nature of a childs difficulties, and allows for more informed formulation of intervention strategies, minimizing the long-term impact of seizures. Even in adults, seizure disorders are rarely static. Patients may report ambiguous or diffuse changes in functioning, which can be more precisely defined with neuropsychological assessment. New onset impairments in cognitive function may signal the need for changes in medication, either because of toxicity or increased seizure activity. Abilities such as attention and concentration are often cited by patients as side effects of medication, but may be difficult to assess at bedside or in clinic.
Neuropsychological examination is useful for detecting subtle changes in cognitive functions that are otherwise difficult to quantify. Patients with debilitating seizures may be considered candidates for epilepsy surgery. Focal resection of the epileptogenic region may be associated with both positive and negative effects on cognitive functioning. When the surgical resection includes functional cortical tissue, deficits in abilities mediated by areas in, and proximal to, the zone of resection may be anticipated. However, functions mediated by cortex distal to the planned resection may improve following surgery.
A commonly cited example of this phenomenon is observed in temporal lobectomy. When seizures originate from the temporal lobe in the language dominant hemisphere, there is a risk to verbal memory and language functions such as naming. However, patients often demonstrate improvement in functions, which are typically mediated by the nondominant hemisphere, such as visual memory and nonverbal reasoning. Understanding the patients preoperative neuropsychological profile aids in counseling the patient about the anticipated outcome and facilitates identification of appropriate candidates for surgery.
Neuropsychological assessment is a noninvasive means of establishing evidence of focal dysfunction in candidates for epilepsy surgery. This is among the most widely recognized contributions of neuropsychology to epilepsy treatment. Seizures are well known to have an impact on patients memory, and specific impairments in memory with relatively well preserved intellectual functioning point to temporal lobe involvement in seizure onset. Assessment of clinical memory in the context of a comprehensive neuropsychological assessment is considered an integral component of any epilepsy surgery evaluation (NIH conference). Evaluating cognitive functioning during intraoperative cortical stimulation or during chronic subdural implants is a cooperative, multidisciplinary venture. Neuropsychologist's must work closely with the surgeon, electro physiologist, neuro radiologists, and others to produce a functional map of the patients brain.
Definition of cortical areas such as Brocas area is determined by function rather than anatomical landmarks. Patients with epilepsy often have anomalous representation of cognitive functions because the seizures precipitated reorganization. When a patient has language symptoms as part of italy or post-italy semiology, precise localization is needed to ensure protection of language function following a resection. Neuropsychological assessment of language during direct cortical stimulation allows the surgeon to precisely identify cortex, which is crucial for aspects of language. Advances in functional imaging hold promise for minimally or completely noninvasive in vivo correlation of anatomy and function. However, there are limitations to the techniques as they are presently available, and they require correlation with more established evaluation techniques prior to widespread acceptance.
Functional imaging with increasingly powerful MR techniques currently supplements more established procedures such as cortical mapping and the IAP. Localization of function via fMRI will greatly facilitate noninvasive evaluation of surgical candidates. However, while techniques such as fMRI may facilitate localization of regions that are activated during performance of cognitive functions such as naming, prediction of risk to function is still dependent upon deactivation paradigms such as cortical stimulation and IAP testing. Localizing techniques are also limited in their ability to provide important information about proficiency of function, which is obtained through more traditional clinical neuropsychological examination techniques. However, prediction of a patients functional status or performance level cannot be obtained from the data. Clinical examination of memory using a combination of verbal memory tests not only helps to localize to medial versus lateral temporal lobe, but allows prediction of the risk of decline for individual patients.
This information is critical for counseling patients about anticipated outcome of temporal lobectomy, and for maximizing expected functional outcome. Neuropsychology and epilepsy continue to have a reciprocal beneficial relationship. Advances in our understanding of cognitive and emotional function are fueled by detailed assessment of patients with epilepsy, which in turn enhances our ability to care for them. The integration of neuropsychology into comprehensive epilepsy care programs is a well-established beginning.
However, the challenge remains to improve the integration of care with patients needs in the community and family. Bibliography: Luria, A. R. Neuropsychological analysis of focal brain lesions. In B. B.
Wolman (Ed. ), Handbook of Clinical Psychology. Hew York: McGraw-Hill, 1965. Christenson A. L. Luria's Neuropsychological Investigation. New York: Spectrum, 1975.
Davidson, L. A. Syndromes of deficits by area of maximal cortical damage. In Rental, R. M.
and Davison, L. A. , Neuropsychological Procedures and Methods, unpublished manual, 1977. Neuropsychological Battery for Epilepsy, Do drill, 1978 Jones-German M, Smith, ML, & Zatorre RJ. Neuropsychological testing for localizing and literalizing the epileptogenic region. In Engel J Surgical treatment of the Epilepsies, Second Edition New York: Raven Press, Ltd. 1993
Free research essays on topics related to: temporal lobe, frontal lobe, areas of the brain, part of the brain, area of the brain
Research essay sample on Part Of The Brain Areas Of The Brain
