Visual memory for faces has been extensively researched, especially regarding the main factors that influence face memorability. However, what we remember exactly about a face, namely, the pictorial content of visual memory, remains largely unclear. The current work aims to elucidate this issue by reconstructing face images from both perceptual and memory-based behavioural data. Specifically, our work builds upon and further validates the hypothesis that visual memory and perception share a common representational basis underlying facial identity recognition. To this end, we derived facial features directly from perceptual data and then used such features for image reconstruction separately from perception and memory data. Successful levels of reconstruction were achieved in both cases for newly-learned faces as well as for familiar faces retrieved from long-term memory. Theoretically, this work provides insights into the content of memory-based representations while, practically, it may open the path to novel applications, such as computer-based ‘sketch artists’.

Visual memory for faces has been extensively researched, especially regarding the main factors that influence face memorability. However, what we remember exactly about a face, namely, the pictorial content of visual memory, remains largely unclear. The current work aims to elucidate this issue by reconstructing face images from both perceptual and memory-based behavioural data. Specifically, our work builds upon and further validates the hypothesis that visual memory and perception share a common representational basis underlying facial identity recognition. To this end, we derived facial features directly from perceptual data and then used such features for image reconstruction separately from perception and memory data. Successful levels of reconstruction were achieved in both cases for newly-learned faces as well as for familiar faces retrieved from long-term memory. Theoretically, this work provides insights into the content of memory-based representations while, practically, it opens the path to novel applications, such as computer-based 'sketch artists'.3Remembering the visual appearance of a known face is a crucial part of everyday life. To date, extensive research has established the impact of specific contextual and intrinsic facial properties on face memorability (e.g., distinctiveness, familiarity, inter-group similarity, race, emotional expression, and trustworthiness, to name a few) [1][2][3][4][5][6][7][8][9] . Yet, much less is currently known about the concrete pictorial information associated with retrieving a face from memory.Arguably, elucidating this issue can provide valuable insights into the nature of the representations subserving face memory and also, into their relationship with face perception. Accordingly, the current work seeks to elucidate the representational content of visual face memory through the novel use of image reconstruction. Previously, reconstruction approaches have been mainly directed at estimating the perceptual representations of an observer from patterns of neural activation 10-14 . Importantly though, reconstruction has not targeted longterm memory and its pictorial content as derived from behavioural data (but see recent work on neural-based image reconstruction from working memory 15 ). To handle this challenge, here, we appeal to a robust reconstruction approach 12 that capitalises on the structure of internal representations as reflected by empirical data irrespective of their modality (e.g., neural or behavioural). Further, this approach has a twofold goal of deriving facial features directly from empirical data and then using them in the process of image reconstruction.Theoretically, at the core of our work lies the concept of face space 16 , a multidimensional construct comprising a population of faces with the property that the distance between any pair of faces reflects their psychological similarity [17][18][19][20] . Critical for our purposes, perceptual face space and its memory-based counterpart may be closely related 21 allowing, in theory, the use of...

Extensive work has demonstrated a decline in face recognition abilities associated with healthy aging. To date, however, there has been limited insight into the nature and the extent of agingrelated alterations in internal face representations. Here, we sought to address these issues by using an image reconstruction approach that capitalizes on the structure of behavioral data to reveal the pictorial content of visual representations. To this end, healthy young and older adults provided similarity judgments with pairs of face images. Facial shape and surface features were subsequently derived from the structure of the data for each participant and combined into image reconstructions of facial appearance. Our findings revealed that image reconstruction was successful for every participant, irrespective of age. However, reconstruction accuracies of shape and surface information were lower for older individuals than young individuals. Specifically, facial features diagnostic for face perception, such as eye shape and skin tone, were reconstructed poorly in older adults relative to young adults. At the same time, we found that age-related effects only accounted for a relatively small proportion of individual variability in face representations. Thus, our results provide novel insight into age-related changes in visual perception, they account for the decline in facial recognition occurring with age and they demonstrate the utility of image reconstruction to uncovering internal representations across a variety of populations.