Running Head: NEUROPSYCHOLOGICAL TESTING
Burke (2009) defines neuropsychological testing as an assessment of cognition, personality, mood and behavior on a patient by a trained and qualified neuropsychologist. This evaluation encompasses interviews, reviews of educational, medical and vocational records and neuropsychological testing which is done with neuropsychological instruments that have been standardized for this purpose. This form of assessment may also include the memory of the patient, language, sensory, intelligence, mobility and aspects of attention and speed. The type of patients who can be referred for neuropsychological testing include patients with a history of head injury, exposure to drugs or alcohol, utero maternal illness, chemical or toxin exposure, learning deficits, slow rate of achieving developmental milestones, dementia, stroke, Parkinson’s disease, seizures or psychiatric disorders.
Neuropsychological testing is beneficial to the patient in that it aids in accurately determining the illness of the patient based on the symptoms. This will result in the patient getting the necessary medical care to cure or manage the condition. It also enables quantification of aspects of emotions, intelligence, and memory especially in cases like Alzheimer’s disease which is characterized by deteriorating memory so that the severity can be determined. This helps the patient to make the necessary adjustments in their lives and also the doctors will now the intensity of the treatment methods they are going to administer. The prognosis done will also identify the strengths and weakness of the patient which will also help in determining the kind of treatment that the patient can handle and if rehabilitation is necessary. It also plays a role in assisting the family of the patient to provide the support needed to the patient. Neuropsychological testing is important in determining if there is presence of brain damage and if there is to what extent it has affected the individual. This application is mostly in trauma cases where neuroimaging does not show the extent which is easily assessed with neuropsychological tests. The actual testing takes from six to twelve hours depending on the kind of information that is required. Less intensive testing may also be done. Extra time is required for the neuropsychologist to go through the records to interpret the results in order to write a formal report (Reitan & Wolfson, 2008).
The information that can be read from a neuropsychological test includes the capacity to understand and articulate language, processing, ability to coordinate visual and spatial factors, short-term memory, long-term memory, the working memory, attention, reasoning and ability to solve problems. The results obtained from a neuropsychological test should put into consideration the age of the patient, cultural background, sex and education. These factors usually limit the conclusions that the neuropsychologist can draw from the records obtained.
Issues that are considered during selection of a neuropsychological test depend on reliability, sensitivity, validity and specificity. Reliability is concerned with reproducibility of the test or set of tests. This means that the results obtained should be consistent. It also means that the results obtained by one examiner should remain stable even when a different administrator performs a similar test, the performance of the test on the same patient by the same administrator but on different occasions and administration of the same test by the same examiner in many occasions.
Validity defines how well the measures of the test produce the required results. The report of the examiner should be similar with what the test does. Validity involves construct validity which refers to whether the test measures what it is supposed to, concurrent validity, whether mew tests give similar results as the existing tests, face validity refers to the ability of the test to appear to measure what it is supposed to, localization validity is the ability of the test to localize focal lesions with accuracy while ecologic validity is the ability of the test to predict real life. Sensitivity refers to the ability of the test to detect even the slightest abnormalities in the functioning of the central nervous system. The sensitivity of a test determines whether the test is able to detect a disorder in a patient. Specificity is involved in differentiating patients with abnormalities from those with no abnormality or with a certain degree of abnormality. This is shown by the score on a test which can either be true positive which allows dysfunctions to be detected through high sensitivity, true negative that has high specificity which allows differentiation of negative from others, false positive which shows sensitivity to dysfunction but lacks the specificity to a particular dysfunction or false negative which shows lack of sensitivity without considering test specificity (Benton, 1992).
The common neuropsychological tests for intellectual functioning are Wechsler Scales, Wechsler Adult Intelligence Scale-Revised (WAIS-R), Wechsler Adult Intelligence Scale-III(WAIS-III), Wechsler Intelligence Scale for Children-IV (WISC-IV) and Stanford-Binet Intelligence Scale-IV. Academic achievement can be tested using Wechsler Individual Achievement Test (WIAT) and Woodcock-John Achievement Test. Boston Naming Test, Multilingual Aphasia Examination, Boston Diagnostic Aphasia Examination and Token test are used for language processing. Visual-spatial processing can be evaluated using Rey-Osterrieth Complex Figure-Copy condition, WAIS Block Design Subtest, Judgment of Line Orientation and Hooper Visual Organization Test. For assessing attention the following tests can be used, Trail Making Tests, Cancellation Tasks, Paced Auditory Serial Addition Test (PASAT) and Digital Span Forward and Reversed. Motor speed and strength is tested using Index finger Tapping, Grooved Pegboard Task, Hand Grip Strength and Thurstone Uni- and Bimanual Coordination Test (Malik, Turner, Sadler, 2009).
Poor performance in neuropsychological tests does not necessarily mean that the person is suffering from brain damage as there are factors that can contribute to decrease the test performance. Factors like emotional problems, Post traumatic disorder, alcohol and depression can reduce IQ tests obtained while anxiety will also interfere with the scores. Post traumatic disorder may be wrongly interpreted to indicate a person had brain damage and vice versa. Age is related to the performance of the test because younger individuals tend to perform better at these tests than older ones. When a person is less educated it might be reflected with lower performance which many would interpret as low IQ thus it is also important to consider the education background of an individual before drawing the conclusions. According to research done using WAIS-R and the influence of culture, the scores indicate that whites perform better than blacks showing that blacks obtain lower overall IQ than whites (Kaufman, McBean & Reynolds, 1988). Due to the inadequacy of neuropsychological tests that are designed for those whose native language is not English, performance for such individuals is usually low indicating that lack of English knowledge can affect the outcomes of the assessment. When a brain damage is determined and established, it is also important for the psychologist to determine whether the injury affects the every day life of the patient (Wilson, 1993).
Neuropsychological assessment deals with assessment of brain damage to an individual. Because the brain is a very sensitive organ, tests should be determined carefully so that they do not affect the individual. It is also important for the administrator of such tests to have the whole background of the patient so that results can be correctly interpreted.
Benton, A. (1992). Clinical Neuropsychology: 1960-1990. Journal of Clinical and Experimental Neuropsychology, 14, 407-417.
Burke, H. L. (2009) Benefits of Neuropsychological Assessment. Retrieved 13 April 2011, from, http://www.brain-injury-therapy.com/services/neuropsychological_testing.htm
Kaufman, A.S., McBean, J.E. and Reynolds, C.R. (1988). Sex, race, residence, region, and educational differences on the II WAIS-R subtests. Journal of Clinical Psychology, 44, 231-248.
Malik, A. B., Turner, M. E., Sadler, C. (2009). Neuropsychological evaluation, Retrieved 13 April 2011, from, http://emedicine.medscape.com/article/317596-overview#a30
Reitan, R. M and Wolfson, D. (2008)The Use of Serial Testing in Evaluating the Need for Comprehensive Neuropsychological Testing of Adults Applied Neuropsychology, 15(1), p21-32, DOI: 10.1080/09084280801917277
Wilson, B.A. (1993). Ecological validity of neuropsychological assessment: Do neuropsychological indexes predict performance in everyday activities? Applied and Preventative Psychology, 2, 209-215.