Reports base rate data for 50 controls and 170 personal injury claimants' self-reported symptoms associated with neuropsychological impairment. These base rates were obtained from claimants with no history of brain injury or toxic exposure and no documented neuropsychological impairments. Personal injury claimants reported high rates of complaints generally recognized as being associated with neuropsychological impairment. For example, 93% reported anxiety or nervousness, 92% sleeping problems, 89% depression, 88% headaches, 79% fatigue, 78% concentration problems, 77% irritability, 65% impatience, 61% feeling disorganized, 59% confusion, 56% loss of efficiency with everyday tasks, 53% memory problems, 44% dizziness, 39% numbness, and 34% word finding problems. These results underscore the need for caution when relying, on self-reported symptoms as evidence of brain damage in patients involved in litigation.