Differences between and within individuals, and subprocesses of face cognition: implications for theory, research and personnel selection

Abstract

Recent investigations of individual differences have demonstrated striking variability in performance both within the same subprocess in face cognition (e.g. face perception), but also between two different subprocesses (i.e. face perception versus face recognition) that are assessed using different tasks (face matching versus face memory). Such differences between and within individuals between and within laboratory tests raise practical challenges. This applies in particular to the development of screening tests for the selection of personnel in real-world settings where faces are routinely processed, such as at passport control. The aim of this study, therefore, was to examine the performance profiles of individuals within and across two different subprocesses of face cognition: face perception and face recognition. To this end, 146 individuals completed four different tests of face matching-one novel tool for assessing proficiency in face perception, as well as three established measures-and two benchmark tests of face memory probing face recognition. In addition to correlational analyses, we further scrutinized individual performance profiles of the highest and lowest performing observers identified per test, as well as across all tests. Overall, a number of correlations emerged between tests. However, there was limited evidence at the individual level to suggest that high proficiency in one test generalized to other tests measuring the same subprocess, as well as those that measured a different subprocess. Beyond emphasizing the need to honour inter-individual differences through careful multivariate assessment in the laboratory, our findings have real-world implications: combinations of tests that most accurately map the task(s) and processes of interest are required for personnel selection.

Keywords: face processing; individual differences; personnel selection; subprocesses.

Figure 1.

Example stimuli and procedures from the six tests that were administered in this study. Analogies of the (a) YBT-10 [43] and (b) FICST [44] (for illustrative purposes, the YBT-10 is reformatted, and the FICST is demonstrated using different identities). In (b), the two identities can be distinguished here based on whether they are marked with a red border. (c) Example match (top) and mismatch (bottom) stimuli from the KFMT-long [37] and (d) represents a trial from the 1-in-10 task [51]. Also depicted are stimuli and procedures employed in the (e) CFMT+ [28] and (f) the MMT [31].

Figure 2.

Distribution of standardized performance observed for the six administered tests. Displayed here are frequencies of (z-scored) accuracy scores per test.

Figure 3.

Visualization of Spearman correlations of performance measures for the six tests employed. Measures considered were accuracy in the YBT-10 and CFMT+, FICST score and d′ in the KFMT-long, 1-in-10 and MMT, respectively. Cell contents indicate individual r values; all (Holm's Bonferroni corrected) correlations reached significance.

Figure 4.

Visualization of observers' performance profiles after ranking based on their overall performance across all tests. Radar plots on the left demonstrate performance for individuals who ranked highest (top row) and lowest (bottom row) across all tests. Blue areas denote individual performance, and the grey areas denote the mean performance across the entire sample. The PSM on the right characterizes the relationship between individual performance profiles for observers ranked according to their overall performance across all tests. The black highlight shows the area of the PSM for high and low performers, respectively.