BACKGROUND: Deficits in attention are commonly identified among patients who have been prenatally exposed to alcohol, and they often affect the ability of the patients to function appropriately in society. METHODS: Eleven adult patients with fetal alcohol syndrome (FAS) or fetal alcohol effects (FAE) were compared with nine adult subjects with no history of prenatal alcohol exposure, using four tests of visually and auditorially mediated attention. RESULTS: In relation to the comparison group, patients with FAS/FAE exhibited substantial deficits in both auditory and visual attention; the auditory deficits were greater. We observed two predominant patterns of deficits among patients with FAS/FAE, one involving both auditory and visual attention problems and the other involving less severe auditory problems and even fewer visual problems. Most subjects with FAS or FAE had some manifestations of attention problems in at least one of the tests of attention used in this study. We present a new graphical representation of individual auditory Continuous Performance Test data across a 6-min period, which, compared with conventional scores, more clearly reveals the markedly disrupted and variable attention patterns displayed by some individuals with FAS or FAE. CONCLUSIONS: These findings suggest that detailed analysis of the pattern of individual performance for each subject is an important aspect of Continuous Performance Test assessment. Our findings further suggest that intellectual performance (intelligence quotient score) alone is not sufficient to account for the patterns of disrupted attention for individuals with FAS/FAE. Assessment of individuals with FAS or FAE should include measurement of attentional functioning in both the visual and auditory modalities.