Brain and Cognition 45, 357–377 (2001) doi:10.1006/brcg.2000.1272, available online at http://www.idealibrary.com on An ERP Study of Famous Face Incongruity Detection in Middle Age Laurence Chaby,* Boutheina Jemel,* Nathalie George,² Bernard Renault,* and Nicole Fiori‡ *Unite ´ de Neurosciences Cognitives et Imagerie Ce ´re ´brale, CNRS UPR 640, LENA, Ho ˆpital de la Salpe ˆtrie `re, 47 bd de l’Ho ˆpital, 75651 Paris cedex 13, France; ²CNRS UPR 640, LENA & Universite ´ Paris VIII, Saint-Denis, France; and ‡CNRS UPR 640, LENA & Universite ´ Paris V, Boulogne Billancourt, France Age-related changes in famous face incongruity detection were examined in middle-aged (mean = 50.6) and young (mean = 24.8) subjects. Behavioral and ERP responses were re- corded while subjects, after a presentation of a ‘‘prime face’’ (a famous person with the eyes masked), had to decide whether the following ‘‘test face’’ was completed with its authentic eyes (congruent) or with other eyes (incongruent). The principal effects of advancing age were (1) behavioral difficulties in discriminating between incongruent and congruent faces; (2) a reduced N400 effect due to N400 enhancement for both congruent and incongruent faces; (3) a latency increase of both N400 and P600 components. ERPs to primes (face encod- ing) were not affected by aging. These results are interpreted in terms of early signs of aging.  2001 Academic Press Key Words: aging; faces; incongruity; priming; memory; ERPs; N170; N400; P600. INTRODUCTION It is commonly accepted that cognitive functions, including perceptual processes, attention, memory, etc., fade with age, and that this is an inevitable part of the aging process (Spirduso, 1995). The relevant literature on aging is extremely large, provid- ing substantial evidence that accuracy rates and response latencies in cognitive tests are respectively impaired and delayed in elderly (Craik & Salthouse, 1992). However, some studies, mainly focused on the behavior of elderly (65 years old and more) in everyday life, have shown many abilities preserved in old age (Baltes, Kliegl, & Dittman-Kohli, 1988; Schweich, Van der Linden, Bre ´dart, Bruyer, Nelles, & Schills, 1992). Although numerous studies have been conducted in order to highlight which cogni- tive processes may be modified with aging (Welford, 1985), this issue remains a matter of debate. Two types of interpretation are commonly distinguishable: one that implies a deficit in general factors and the other that invokes the impairments of some specific processes (for review, see Isingrini & Taconnat, 1997). This work was supported in part by grants from the GDR CNRS—industry ‘Cosmetiques et Parfum’ (Grant 222). The authors thank Ms. F. Bouchet and Mr. J. C. Bourzeix for assistance with data collection and analyses. The authors are grateful to the participants in this study for generously giving their time. Reprint requests should be addressed to Laurence Chaby, Unite ´ de Neurosciences Cognitives et Imagerie Ce ´re ´brale, CNRS UPR 640, LENA, Ho ˆpital de la Salpe ˆtrie `re, 47 bd de l’Ho ˆpital, 75651 Paris cedex 13, France. Fax: (33-1) 45 86 25 37. E-mail: laurence.chaby@chups.jussieu.fr. 357 0278-2626/01 $35.00 Copyright  2001 by Academic Press All rights of reproduction in any form reserved.