Postinfectious neuromyasthenia (PIN) is a clinical syndrome of protracted and incomplete recovery after an apparent viral-like illness. Medical investigation yields few abnormalities which might account for the symptomatology. A substantial number of PIN patients complain of cognitive changes. Specific complaints include impaired attention, concentration and abstraction skills. This study was designed to systematically investigate whether the aforementioned subjective complaints could be quantified objectively using standard neuropsychological instruments. Results indicated that on all tests but one, the subjects' performances were significantly higher than those of their age matched groups in the normative data. Specifically, PIN patients scored significantly better than their age matched norms on tests of concentration, attention and abstraction. What is most striking is the discrepancy between the subjective complaints of cognitive impairment and the objective results of the subjects' performances on all tests. These findings suggest that psychological factors may play an important role in the cognitive functioning of individuals diagnosed with postinfectious neuromyasthenia.