The temporal dynamics of familiar face recognition: Event-related brain potentials reveal the efficient activation of facial identity representations.

While it is widely known that humans are typically highly accurate at recognizing familiar faces, it is less clear how efficiently recognition is achieved. In a series of three experiments, we used event-related brain potentials (ERP) in a repetition priming paradigm to examine the efficiency of familiar face recognition. Specifically, we varied the presentation time of the prime stimulus between 500 ms and 33 ms (Experiments 1 and 2), and additionally used backward masks (Experiment 3) to prevent the potential occurrence of visual aftereffects.

How neural representations of newly learnt faces change over time: Event-related brain potential evidence for overnight consolidation.

Previous experiments have shown that a brief encounter with a previously unfamiliar person leads to the establishment of new facial representations, which can be activated by completely novel pictures of the newly learnt face. The present study examined how stable such novel neural representations are over time, and, specifically, how they become consolidated within the first 24 h after learning. Using event-related brain potentials (ERPs) in a between-participants design, we demonstrate that clear face familiarity effects in the occipito-temporal N250 are evident immediately after learning.

Personal familiarity of faces, animals, objects, and scenes: Distinct perceptual and overlapping conceptual representations.

While face, object, and scene recognition are often studied at a basic categorization level (e.g. "a face", "a car", "a kitchen"), we frequently recognise individual items of these categories as unique entities (e.

Developing familiarity during the first eight months of knowing a person: A longitudinal EEG study on face and identity learning.

It is well-established that familiar and unfamiliar faces are processed differently, but surprisingly little is known about how familiarity builds up over time and how novel faces gradually become represented in the brain. Here, we used event-related brain potentials (ERPs) in a pre-registered, longitudinal study to examine the neural processes accompanying face and identity learning during the first eight months of knowing a person. Specifically, we examined how increasing real-life familiarity affects visual recognition (N250 Familiarity Effect) and the integration of person-related knowledge (Sustained Familiarity Effect, SFE).

How quickly do we learn new faces in everyday life? Neurophysiological evidence for face identity learning after a brief real-life encounter.

Faces learnt in a single experimental session elicit a familiarity effect in event-related brain potentials (ERPs), with more negative amplitudes for newly learnt relative to unfamiliar faces in the N250 component. However, no ERP study has examined face learning following a brief real-life encounter, and it is not clear how long it takes to learn new faces in such ecologically more valid conditions. To investigate these questions, the present study examined whether robust image-independent representations, as reflected in the N250 familiarity effect, could be established after a brief unconstrained social interaction by analysing the ERPs elicited by highly variable images of the newly learnt identity and an unfamiliar person.

Characterizing the shared signals of face familiarity: Long-term acquaintance, voluntary control, and concealed knowledge.

In a recent study using cross-experiment multivariate classification of EEG patterns, we found evidence for a shared familiarity signal for faces, patterns of neural activity that successfully separate trials for familiar and unfamiliar faces across participants and modes of familiarization. Here, our aim was to expand upon this research to further characterize the spatio-temporal properties of this signal. By utilizing the information content present for incidental exposure to personally familiar and unfamiliar faces, we tested how the information content in the neural signal unfolds over time under different task demands - giving truthful or deceptive responses to photographs of genuinely familiar and unfamiliar individuals.

Event-related brain potential correlates of the other-race effect: A review.

People are better at remembering own-race relative to other-race faces. Here, we review event-related brain potential (ERP) correlates of this so-called other-'race' effect (ORE) by discussing three critical aspects that characterize the neural signature of this phenomenon. First, difficulties with other-race faces initially emerge during perceptual processing, which is indexed by an increased N170.

The time it takes to truly know someone: Neurophysiological correlates of face and identity learning during the first two years.

How long does it take to truly know a person? To answer this question, we investigated how event-related brain potential (ERP) correlates of facial familiarity (N250) and the integration of identity-specific knowledge (Sustained Familiarity Effect, SFE) develop over time. Sixty undergraduate students from three year groups were tested with images of a university friend (with two, 14, and 26 months of familiarity for Year 1, Year 2, and Year 3 students), a highly familiar friend from home, and an unfamiliar identity. While clear ERP familiarity effects for home friends were observed in all groups, university friends yielded a clear N250 effect but only a small SFE in Year 1.

The role of the eye region for familiar face recognition: Evidence from spatial low-pass filtering and contrast negation.

What information is used for familiar face recognition? While previous research suggests a particular importance of the eye region, information from the rest of the face also needs to be integrated. What type of information is used in conjunction with the eyes is largely unclear. In three experiments, participants were asked to recognise so-called face chimeras, in which the eye region was not manipulated, while the rest of the face was either presented in negative contrast (contrast chimeras) or low-pass filtered (blur chimeras).

Familiarity is familiarity is familiarity: Event-related brain potentials reveal qualitatively similar representations of personally familiar and famous faces.

Humans excel in familiar face recognition, but often find it hard to make identity judgements of unfamiliar faces. Understanding of the factors underlying the substantial benefits of familiarity is at present limited, but the effect is sometimes qualified by the way in which a face is known-for example, personal acquaintance sometimes gives rise to stronger familiarity effects than exposure through the media. Given the different quality of personal versus media knowledge, for example in one's emotional response or level of interaction, some have suggested qualitative differences between representations of people known personally or from media exposure.

Detecting a viewer's familiarity with a face: Evidence from event-related brain potentials and classifier analyses.

Human observers recognize the faces of people they know efficiently and without apparent effort. Consequently, recognizing a familiar face is often assumed to be an automatic process beyond voluntary control. However, there are circumstances in which a person might seek to hide their recognition of a particular face.

Recognising other-race faces is more effortful: The effect of individuation instructions on encoding-related ERP Dm effects.

Humans are better at recognising faces from their own vs. another ethnic background. Socio-cognitive theories of this own-race bias (ORB) propose that reduced recognition of other-race faces results from less motivation to attend to individuating information during encoding.

Neural Correlates of Own- and Other-Face Perception in Body Dysmorphic Disorder.

Background: Body dysmorphic disorder (BDD) is characterized by an excessive preoccupation with one or more perceived flaws in one's own appearance. Previous studies provided evidence for deficits in configural and holistic processing in BDD. Preliminary evidence suggests abnormalities at an early stage of visual processing.

Learning own- and other-race facial identities: Testing implicit recognition with event-related brain potentials.

Exposure to varying images of the same person can encourage the formation of a representation that is sufficiently robust to allow recognition of previously unseen images of this person. While behavioural work suggests that face identity learning is harder for other-race faces, the present experiment investigated the neural correlates underlying own- and other-race face learning. Participants sorted own- and other-race identities into separate identity clusters and were further familiarised with these identities in a matching task.

Later but not early stages of familiar face recognition depend strongly on attentional resources: Evidence from event-related brain potentials.

In everyday life we usually recognise personally familiar faces efficiently and without apparent effort. This study examined to which extent the neural processes involved in recognising personally familiar faces depend on attentional resources by analysing event-related brain potentials. In two experiments, participants were presented with multiple ambient images of highly personally familiar and unfamiliar faces and pictures of butterflies, with a letter string superimposed on each image.

Intentionally remembering or forgetting own- and other-race faces: Evidence from directed forgetting.

People are better at remembering faces of their own relative to another ethnic group. This so-called own-race bias (ORB) has been explained in terms of differential perceptual expertise for own- and other-race faces or, alternatively, as resulting from socio-cognitive factors. To test predictions derived from the latter account, we examined item-method directed forgetting (DF), a paradigm sensitive to an intentional modulation of memory, for faces belonging to different ethnic and social groups.

Learning own- and other-race facial identities from natural variability.

Exposure to multiple varying face images of the same person encourages the formation of identity representations which are sufficiently robust to allow subsequent recognition from new, never-before seen images. While recent studies suggest that identity information is initially harder to perceive in images of other- relative to own-race identities, it remains unclear whether these difficulties propagate to face learning, that is, to the formation of robust face representations. We report two experiments in which Caucasian and East Asian participants sorted multiple images of own- and other-race persons according to identity in an implicit learning task and subsequently either matched novel images of learnt and previously unseen faces for identity (Experiment 1) or made old/new decisions for new images of learnt and unfamiliar identities (Experiment 2).

A Robust Neural Index of High Face Familiarity.

Humans are remarkably accurate at recognizing familiar faces, whereas their ability to recognize, or even match, unfamiliar faces is much poorer. However, previous research has failed to identify neural correlates of this striking behavioral difference. Here, we found a clear difference in brain potentials elicited by highly familiar faces versus unfamiliar faces.

Properties of familiar face representations: Only contrast positive faces contain all information necessary for efficient recognition.

It is difficult to recognize the identity of a face presented in negative contrast. This difficulty, however, is substantially reduced when only the eye region is contrast positive in an otherwise negative face image, and recognition of these so-called contrast chimeras approaches performance with full positive faces. This apparently similar accuracy has led researchers to suggest that familiar face representations are built around the eye region.

Enhancement of face-sensitive ERPs in older adults induced by face recognition training.

A common cognitive problem reported by older people is compromised face recognition, which is often paralleled by age-related changes in face-sensitive and memory-related components in event-related brain potentials (ERPs). We developed a new training using photorealistic caricatures based on evidence that caricatures are beneficial for people with compromised face processing. Twenty-four older participants (62-75 yrs, 13 female) completed 12 training sessions (3 per week, 60 min each) and 24 older participants (61-76 yrs, 12 female) acted as controls.

Same-gender distractors are not so easy to reject: ERP evidence of gender categorization.

Social categorization appears to be an automatic process that occurs during person perception. Understanding social categorization better is important because mere categorization can lead to stereotype activation and, in turn, to discrimination. In the present study we used a novel approach to examine event-related potentials (ERPs) of gender categorization in the "Who said what?" memory paradigm, thus allowing for a more in-depth understanding of the specific mechanisms underlying identity versus categorization processing.

Inequality between biases in face memory: Event-related potentials reveal dissociable neural correlates of own-race and own-gender biases.

Humans are more accurate at remembering faces from their own relative to a different ethnic group (own-race bias). Moreover, better memory for faces from an observer's own relative to the other-gender (own-gender bias) has also been reported, particularly for female participants. Theoretical explanations for these effects either emphasize differential perceptual expertise or socio-cognitive factors.

Age-related differences in face recognition: Neural correlates of repetition and semantic priming in young and older adults.

Difficulties in person recognition are among the common complaints associated with cognitive ageing. The present series of experiments therefore investigated face and person recognition in young and older adults. The authors examined how within-domain and cross-domain repetition as well as semantic priming affect familiar face recognition and analyzed both behavioral and event-related brain potential (ERP) measures to identify specific processing stages of age-related deficits.