Brain damage - whether caused through disease or injury - may result in cognitive deficits (specifically in motor, intellectual or emotional functioning of the patient). Neuropsychological assessment aims to not only confirm the existence of and determine the cause of cognitive impairments, but (based on that knowledge) to also address pathways to rehabilitation of patients and recovery of function (Martin, 2006).
Typical neuropsychological assessment may involve a series of standardised tests, referred to as a ‘test battery’. Examples of widely used test batteries are the Halstead-Reitan and the Wechsler Adult Intelligence Scale – Revised (WAIS-R) which both include measures of verbal and non-verbal intelligence. Alternatively, a flexible selection of individual tests may be employed to measure language ability (e.g. Boston Naming Test) reasoning and concept formation(e.g. Wisconsin Card Sorting Test) and estimates of premorbid intelligence (e.g. National Adult reading Test). Poor performance on any single test may point to a specific area (localisation) of brain damage. If a patient performs badly on a stream of tests, this may be indicative of more widespread damage (Stirling & Elliot, 2008).
Assessor-patient interaction, patient compliance and malingering are just some of the important issues facing those who administer neuropsychological tests. Individual examiners may interact differently with patients leading to unintentional bias or over-familiarity. A patient suffering from depression or other mood disorders may not be in a fit state to be tested, leading to poor compliance. A patient who deliberately tries to perform badly on tests can be a potentially very series problem from a legal point of view. Computer-based neuropsychological assessment tests such as the CANTAB (Cambridge Automated Neuropsychological Assessment Battery) may go some way in addressing inter-tester variability and other similar issues (Martin, 2006).
References
Martin, G. N. (2006). Neuropsychological assessment. In Human Neuropsychology (2nd ed.). Essex: Pearson Education Ltd
Stirling, J. & Elliot, R. (2008). Neuropsychological assessment. In Introducing Neuropsychology (2nd ed.). Hove: Psychology Press
