Introduction

Neuropsychological assessment is the normatively informed application of performance-based assessments of various cognitive skills. Typically, neuropsychological assessment is performed with a battery approach, which involves tests of a variety of cognitive ability areas, with more than one test per ability area. These ability areas include skills such as memory, attention, processing speed, reasoning, judgment, and problem-solving, spatial, and language functions. These assessments are commonly performed in conjunction with assessments designed to examine lifelong academic and cognitive achievement and potential,¹ for a variety of reasons described below. The assessment battery can be standardized or targeted to the individual participant in the assessment. Assessment data may be collected either directly by a psychologist or by a trained examiner, who performs and scores assessments and delivers them to the neuropsychologist. While neuropsychological assessments were originally targeted at individuals who had experienced brain injuries in wartime,² the populations for whom neuropsychological assessments are useful spans the whole range of neuropsychiatric conditions.³

Neuropsychological tests are intrinsically performance-based. They are structured to require individuals to exercise their skills in the presence of an examiner/observer. Self-reports of functioning, as well as observations of behavior while performing testing, are critically important pieces of information, as described below. Self-reports of functioning are often affected by the presence of neuropsychiatric conditions,⁴ and do not have the same value as performance under standard conditions, which is compared with normative standards. A critical concept in neuropsychological assessment is normative comparison.⁵ This involves taking the performance of an individual at the time they are tested and comparing that performance to reference groups of the same age, sex, race, and educational attainment. All of these demographic factors impact performance on the tests in a neuropsychological assessment battery, and interpreting the test performance of people, regardless of the illness or injury that they have experienced, is based on comparisons with individuals who are similar to them. These normative comparisons allow for determination whether an individual is performing as would be expected, given their lifetime levels of achievements and their educational attainment, or if their performance is poorer than expected. Performance that is poorer than expectations can be quantified and interpreted accordingly.