Thirty-two silicone breast implant patients scored in the mild to moderate range of impairment on the Halstead-Reitan Neuropsychological Battery. An unusual number of patients had positive tests for antinuclear antibody on immunological testing and a high incidence of EEG abnormalities were found. Personality testing revealed an MMPI profile which is typical for neuropsychologically impaired subjects but components were consistent with extreme emotional distress. None of the subjects were near the cutoff score for malingering or faking bad on the F-K index of the MMPI. There was no apparent relationship between length of exposure and the severity of neurological impairment. Also, explanted subjects performance was not improved when compared to subjects whose implants were still in place.