Right posterior brain-damaged patients are poor at assessing the age of a face

The ability to order unknown faces by age was investigated in right and left brain-damaged patients, divided into posterior and non-posterior groups on the basis of CT scan findings. A face recognition test and a figure ground discrimination test were also given. All three tests were affected by brain damage, but their sensitivity to the locus and side of lesion varied. While no hemispheric difference was found on the figure ground discrimination test, the face age test significantly discriminated patients with right posterior injury from any other brain-damaged group. The face recognition test occupied an intermediate position, with right posterior patients significantly impaired in comparison with right non-posterior patients and marginally impaired with respect to left posterior patients. Aphasia did not affect the performance of left brain-damaged patients on any of the tests. The findings are interpreted as evidence that damage of the right posterior hemisphere areas disrupts the structural encoding of visual information. Four prosopagnosic patients were also tested. Only those showing signs of apperceptive agnosia failed on the face age test.