intelligence and academic abilities, attention, executive function, verbal and language abilities, visuospatial skills, memory (anterograde, retrograde), and personality and affect.

In order to apply neuropsychological tests to clinical assessment, the technique used must allow the clinician first to document brain damage attributable to neurotoxicant exposure (from subtle to severe) and second, to feel comfortable attributing any observed deficits to neurotoxicant exposure rather than some other cause. It is important to explicitly rule out other potential causes of impairment such as age, education, smoking, alcohol use, developmental disorders, psychiatric disorders, neurological disorders, and motivational states in which persons consciously or unconsciously sabotage their own test performance.

A recent study of Oregon veterans investigated psychosocial, neuropsychological, and neurobehavioral elements to determine objective memory and attention impairment. The population-based study used questionnaires as well as clinical examinations to identify behavioral, psychosocial, and performance disorders. Results indicate that neurobehavioral tests can identify veterans with objective deficits in attention or memory and cognitive processes (Anger, 1996, Unpublished presentation). Whether these objective deficits result in clinical impairments has not yet been documented. In addition, although neurotoxic chemical exposure is one possible explanation for these outcomes, other possibilities exist.