Chronic insomnia and cognitive impairment are both common complaints among older adults. Even so, only a few studies have examined the effects of chronic insomnia on cognitive functioning among the elderly, and the results of these studies are contradictory. The authors therefore examined whether insomnia is associated with changes in cognitive functioning among elderly people. The study population comprised two groups: 64 older adult subjects without sleep disorders, and 48 older adult insomniacs. All subjects were living independently in the community and were in good clinical condition. The cognitive capacity of each subject was tested at the subject's home using the computerized "MindFit" test (CogniFit, Inc.). The results demonstrate that chronic insomnia in older adults is associated with impairment in cognitive functioning. Specifically, we found that older people suffering from late-life insomnia exhibit significantly reduced performance in memory span, allocating attention to a target, time estimation, working memory and integration of two dimensions. The present findings suggest that late-life insomnia may be one of the factors contributing to the decline in cognitive functioning seen among older people. Thus, it is particularly important for health care practitioners to screen for, evaluate and treat insomnia symptoms in the elderly. The findings of this study offer hope that treatment of insomnia in older adults can have beneficial effects in improving cognitive functioning in these patients. Therefore, attention to and effective treatment of chronic insomnia in older persons may not only improve the quality of their nighttime sleep, but conceivabLy, may also maintain cognitive function, thus improving their overall quality of life.