Abstract
Are deficits in face recognition in healthy older adults (OA) similar or different from those in young adults with developmental prosopagnosia (DP)? In the Cambridge Face Memory Test (Duchaine & Nakayama, 2006), OAs performed worse than young controls but their average score was well within 2SD of the young control mean. DPs (n=5, age range=21–46) showed a severe impairment in the memory test compared to both young controls and OAs. Both OAs and DPs demonstrated a strong face inversion effect in the memory test. Groups also differed on a sequential matching task which presented one of the stimulus categories including unfamiliar faces, greebles (Gautheir & Tarr, 1997) and simple geometric figures composed of two elements. In each trial, a first stimulus was displayed for 500 ms, followed by a mask, then a second stimulus was shown. Viewpoints between the first and second stimuli were varied (no change or 30° change). With face and greeble stimuli, OAs performed worse than young controls in all viewpoint conditions. Additionally, they were poor at detecting a feature change in simple geometric figures. DPs demonstrated a deficit for faces and simple geometric objects only when there was a change in viewpoint. With greebles, DPs' accuracy was comparable to that of young controls in all viewpoint conditions but reaction time was significantly slower. Overall, the data suggest that face perception is more affected by aging than face memory and that age-related decline extends to object categories. In contrast, face processing deficits in the DPs appear to arise at higher levels, which may reflect a disruption in building a view-invariant representation and transferring it to long-term memory.
This work was supported by a Canadian Institutes of Health Research grant to M.M. and C.L.G. (MOP737106301). Dr. Grady also is supported by the Canada Research Chairs program, the Ontario Research Fund, and the Canadian Foundation for Innovation.