[Show abstract][Hide abstract] ABSTRACT: Many research questions require a within-class object recognition task matched for general cognitive requirements with a face recognition task. If the object task also has high internal reliability, it can improve accuracy and power in group analyses (e.g., mean inversion effects for faces vs. objects), individual-difference studies (e.g., correlations between certain perceptual abilities and face/object recognition), and case studies in neuropsychology (e.g., whether a prosopagnosic shows a face-specific or object-general deficit). Here, we present such a task. Our Cambridge Car Memory Test (CCMT) was matched in format to the established Cambridge Face Memory Test, requiring recognition of exemplars across view and lighting change. We tested 153 young adults (93 female). Results showed high reliability (Cronbach's alpha = .84) and a range of scores suitable both for normal-range individual-difference studies and, potentially, for diagnosis of impairment. The mean for males was much higher than the mean for females. We demonstrate independence between face memory and car memory (dissociation based on sex, plus a modest correlation between the two), including where participants have high relative expertise with cars. We also show that expertise with real car makes and models of the era used in the test significantly predicts CCMT performance. Surprisingly, however, regression analyses imply that there is an effect of sex per se on the CCMT that is not attributable to a stereotypical male advantage in car expertise.
Full-text · Article · Oct 2011 · Behavior Research Methods
[Show abstract][Hide abstract] ABSTRACT: The Cambridge Face Memory Test (CFMT, Duchaine & Nakayama, 2006) provides a validated format for testing novel face learning and has been a crucial instrument in the diagnosis of developmental prosopagnosia. Yet, some individuals who report everyday face recognition symptoms consistent with prosopagnosia, and are impaired on famous face tasks, perform normally on the CFMT. Possible reasons include measurement error, CFMT assessment of memory only at short delays, and a face set whose ethnicity is matched to only some Caucasian groups. We develop the "CFMT-Australian" (CFMT-Aus), which complements the CFMT-original by using ethnicity better matched to a different European subpopulation. Results confirm reliability (.88) and validity (convergent, divergent using cars, inversion effects). We show that face ethnicity within a race has subtle but clear effects on face processing even in normal participants (includes cross-over interaction for face ethnicity by perceiver country of origin in distinctiveness ratings). We show that CFMT-Aus clarifies diagnosis of prosopagnosia in 6 previously ambiguous cases. In 3 cases, this appears due to the better ethnic match to prosopagnosics. We also show that face memory at short (<3-min), 20-min, and 24-hr delays taps overlapping processes in normal participants. There is some suggestion that a form of prosopagnosia may exist that is long delay only and/or reflects failure to benefit from face repetition.
Full-text · Article · Mar 2011 · Cognitive Neuropsychology
[Show abstract][Hide abstract] ABSTRACT: Holistic processing and face space coding are widely considered primary perceptual mechanisms behind good face recognition. Here, however, we present the case of S.P., a developmental prosopagnosic who demonstrated severe impairments in face memory and face perception, yet showed normal holistic processing and face space coding. Across three composite experiments, S.P. showed normal-strength holistic processing for upright faces and no composite effect for inverted faces. Across five aftereffect experiments, S.P. showed normal-sized face aftereffects, which derived normally from face space rather than shape-generic mechanisms. The case of S.P. implies: (a) normal holistic processing and face space coding can be insufficient for good face recognition even when present in combination; and (b) the focus of recent literature on holistic processing and face space should be expanded to include other potential face processing mechanisms (e.g., part-based processing). Our article also highlights the importance of internal task reliability in drawing inferences from single-case studies.
Full-text · Article · Dec 2010 · Cognitive Neuropsychology