A previously described test for prosopo-affective agnosia (impairment of facial affect recognition) had been applied in 14 disoriented elderly patients with chronic organic brain syndrome, 14 fully oriented elderly patients with non-organic psychiatric disorders, and 14 normal volunteers. In this re-test study of 37 of the 42 subjects, after a six-month interval, the test was found to be reliable (r = .75, p less than .001). The test was also more sensitive in detecting organic disorders than were other frequently applied neuropsychiatric tests. Prosopo-affective agnosia (PAA) appeared unrelated to prosopo-agnosia (PA) (r = .082, ns). Some patients who had the ability to recognize famous faces and faces of ward personnel were severely impaired in the ability to recognize facial affect. The deterioration was more pronounced for the recognition of sadness and anger than for happiness, indicating that patients with this impairment had reverted to an infantile mode of facial-affect recognition. This reversal is another example of the neurologic regression that characterizes dementia.