The concept of age is a fundamental aspect of mental life. However, it is not clear whether age is more an autobiographical detail we remember, a number indicating the years we live, or an inherent part of our subjective self-perception. An insight may be inferred from the underlying neuroanatomy. To investigate the neuroanatomical basis of age perception, we used lesion analysis in 7 patients with age-disorientation due to acute stroke, as compared to a control group of 9 age-oriented patients. Age-disoriented patients underestimated their age by 17.8±5.0 years. Lesion analysis indicated main regions of overlap in the insula, as well as the rolandic operculum and the supramarginal gyrus, predominantly in the left hemisphere, as compared to stroke patients without age-disorientation. Since these regions are involved in the cognitive functions of self-referenced time-processing, including its emotional aspects, our data suggest that these functions are intimately related to age perception.