Ageing faces in ageing minds: A review on the own-age bias in face recognition

The effects of age bias on neural correlates of successful and unsuccessful response inhibition in younger and older adults

Facilitating communication between generations has become increasingly important. However, individuals often demonstrate a preference for their own age group, which can impact social interactions, and such bias in young adults even extends to inhibitory control. To assess whether older adults also experience this phenomenon, a group of younger and older adults completed a Go/NoGo task incorporating young and old faces, while undergoing functional magnetic resonance imaging. Within the networks subserving successful and unsuccessful response inhibition, patterns of activity demonstrated distinct neural age bias effects in each age group. During successful inhibition, the older adult group demonstrated significantly increased activity to other-age faces, whereas unsuccessful inhibition in the younger group produced significantly enhanced activity to other-age faces. Consequently, the findings of the study confirm that neural responses to successful and unsuccessful inhibition can be contingent on the stimulus-specific attribute of age in both younger and older adults. These findings have important implications in regard to minimizing the emergence of negative consequences, such as ageism, as a result of related implicit biases.

Effects of aging on face processing: An ERP study of the own-age bias with neutral and emotional faces

Older adults systematically show an enhanced N170 amplitude during the visualization of facial expressions of emotion. The present study aimed to replicate this finding, further investigating if this effect is specific to facial stimuli, present in other neural correlates of face processing, and modulated by own-age faces. To this purpose, younger (n = 25; M_age = 28.36), middle-aged (n = 23; M_age = 48.74), and older adults (n = 25; M_age = 67.36) performed two face/emotion identification tasks during an EEG recording. The results showed that groups did not differ regarding P100 amplitude, but older adults had increased N170 amplitude for both facial and non-facial stimuli. The event-related potentials analysed were not modulated by an own-age bias, but older faces elicited larger N170 in the Emotion Identification Task for all groups. This increased amplitude may reflect a higher ambiguity of older faces due to age-related changes in their physical features, which may elicit higher neural resources to decode. Regarding P250, older faces elicited decreased amplitudes than younger faces, which may reflect a reduced processing of the emotional content of older faces. This interpretation is consistent with the lower accuracy obtained for this category of stimuli across groups. These results have important social implications and suggest that aging may hamper the neural processing of facial expressions of emotion, especially for own-age peers.

The role of implicit social bias on holistic processing of out-group faces

Although faces of in-group members are generally thought to be processed holistically, there are mixed findings on whether holistic processing remains robust for faces of out-group members and what factors contribute to holistic processing of out-group faces. This study examined how implicit social bias, experience with out-group members, and ability to process in-group faces holistically might predict the magnitude of holistic processing for faces of two out-groups: other-race and other-age groups. In Experiment 1, Caucasian participants viewed Caucasian (own-race) and East Asian (other-race) faces. In Experiment 2, young adult participants viewed young adult (own-age) and baby (other-age) faces. Each participant completed a composite task with in-group and out-group faces, an implicit association test, and questionnaires about their experience with in-group and out-group members. We found that while the participants had relatively extensive experience with the other-race group, they had limited experience with the other-age group. Nonetheless, implicit social bias was found to positively predict the magnitude of holistic processing for both other-race and other-age faces. Exploratory analyses on the interactions among the predictors suggest that the effect of implicit social bias was primarily observed in participants with strong holistic processing ability of in-group faces but with low level of experience with members of the out-groups. These findings suggest that observers utilize different kinds of information when processing out-group faces, and that social features, such as race or age, are incorporated to influence how out-group faces are processed efficiently.

Biases in human perception of facial age are present and more exaggerated in current AI technology

Our estimates of a person's age from their facial appearance suffer from several well-known biases and inaccuracies. Typically, for example, we tend to overestimate the age of smiling faces compared to those with a neutral expression, and the accuracy of our estimates decreases for older faces. The growing interest in age estimation using artificial intelligence (AI) technology raises the question of how AI compares to human performance and whether it suffers from the same biases. Here, we compared human performance with the performance of a large sample of the most prominent AI technology available today. The results showed that AI is even less accurate and more biased than human observers when judging a person's age-even though the overall pattern of errors and biases is similar. Thus, AI overestimated the age of smiling faces even more than human observers did. In addition, AI showed a sharper decrease in accuracy for faces of older adults compared to faces of younger age groups, for smiling compared to neutral faces, and for female compared to male faces. These results suggest that our estimates of age from faces are largely driven by particular visual cues, rather than high-level preconceptions. Moreover, the pattern of errors and biases we observed could provide some insights for the design of more effective AI technology for age estimation from faces.

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. Second, as evidenced by 'difference due to subsequent memory' effects, more effortful processing of other-race faces is needed for successful encoding into long-term memory. Third, ERP old/new effects reveal that a stronger engagement of processing resources is also required for successful retrieval of other-race faces from memory. The ERP evidence available to date thus suggests widespread ethnicity-related modulations during both perceptual and mnemonic processing stages. We further discuss how findings from the ORE compared with potentially related memory biases (e.g. other-gender or other-age effects) and how ERP findings inform the ongoing debate regarding the mechanisms underlying the ORE. Finally, we outline open questions and potential future directions with an emphasis on using multiple, ecologically more valid 'ambient' images for each face to assess the ORE in paradigms that capture identity rather than image recognition.

An older adult advantage in autobiographical recall

This pre-registered online study aimed to measure the effect of environmental support on age-differences in autobiographical memory alongside memory for images. Young and older adults reported autobiographical memories about which they regularly thought (high environmental support through practice) or that were experimentally cued to be mundane (low environmental support). The support manipulation was also applied to descriptions of images that were produced whilst images remained on screen (high support) or produced from memory (low support). In line with existing theory, support disproportionately benefitted older adults in the quantity of information produced. However, analysis of the autobiographical descriptions showed no age deficit in reporting episodic detail, in contrast to much of the existing literature. A second group of young and older adults also evaluated the descriptions produced, and older adults' descriptions were consistently rated as higher quality than young adults' descriptions across several dimensions, such as vividness and clarity. An unplanned meta-analysis was conducted to assess if a publication bias existed in the literature favoring the reporting of age-deficits in producing episodic detail in autobiographical memory: there was no evidence for a bias and the modal result of age deficits was generally supported. A key distinction is that the current study was conducted online - evidence is presented to argue that older adults may perform better at autobiographical memory tasks outside the lab.

The hippocampus shows an own-age bias during unfamiliar face viewing

The present study investigated the neural correlates of the own-age bias for face recognition in a repetition suppression paradigm. Healthy young and older adults viewed upright and inverted unfamiliar faces. Some of the upright faces were repeated following one of two delays (lag 0 or lag 11). Repetition suppression effects were observed in bilateral fusiform cortex. However, there were no significant effects indicating an own-age bias in repetition suppression. The absence of these effects is arguably inconsistent with perceptual expertise accounts of own-age biases in face processing. By contrast, the right anterior hippocampus showed an own-age bias (greater activity for own-age compared to other-age faces) when viewing an unfamiliar face for the first time. Given the importance of the hippocampus for episodic memory encoding, we conjecture that the increased hippocampal activity for own-age relative to other-age faces reflects differential engagement of neural processes supporting the episodic encoding of faces and might provide insight into the neural underpinnings of own-age biases in face recognition memory.

How facial aging affects perceived gender: Insights from maximum likelihood conjoint measurement

Conjoint measurement was used to investigate the joint influence of facial gender and facial age on perceived gender (Experiment 1) and perceived age (Experiment 2). A set of 25 faces was created, covarying independently five levels of gender (from feminine to masculine) and five levels of age (from young to old). Two independent groups of observers were presented with all possible pairs of faces from this set and compared which member of the pair appeared as more masculine (Experiment 1) or older (Experiment 2). Three nested models of the contribution of gender and age to judgment (i.e., independent, additive, and saturated) were fit to the data using maximum likelihood. The results showed that both gender and age contributed to the perceived gender and age of the faces according to a saturated observer model. In judgments of gender (Experiment 1), female faces were perceived as more masculine as they became older. In judgments of age (Experiment 2), young faces (age 20 and 30) were perceived as older as they became more masculine. Taken together, the results entail that: (a) observers integrate facial gender and age information when judging either of the dimensions, and that (b) cues for femininity and cues for aging are negatively correlated. This correlation exerts stronger influence on female faces, and can explain the success of cosmetics in concealing signs of aging and exaggerating sexually dimorphic features.

Stereotypical Processing of Emotional Faces: Perceptual and Decisional Components

People tend to associate anger with male faces and happiness or surprise with female faces. This angry-men-happy-women bias has been ascribed to either top-down (e.g., well-learned stereotypes) or bottom-up (e.g., shared morphological cues) processes. The dissociation between these two theoretical alternatives has proved challenging. The current effort addresses this challenge by harnessing two complementary metatheoretical approaches to dimensional interaction: Garner's logic of inferring informational structure and General Recognition Theory-a multidimensional extension of signal detection theory. Conjoint application of these two rigorous methodologies afforded us to: (a) uncover the internal representations that generate the angry-men-happy-women phenomenon, (b) disentangle varieties of perceptual (bottom-up) and decisional (top-down) sources of interaction, and (c) relate operational and theoretical meanings of dimensional independence. The results show that the dimensional interaction between emotion and gender is generated by varieties of perceptual and decisional biases. These outcomes document the involvement of both bottom-up (e.g., shared morphological structures) and top-down (stereotypes) factors in social perception.

Older Adults Automatically Detect Age of Older Adults' Photographs: A Visual Mismatch Negativity Study

The human face is one of the most frequently used stimuli in vMMN (visual mismatch negativity) research. Previous studies showed that vMMN is sensitive to facial emotions and gender, but investigations of age-related vMMN differences are relatively rare. The aim of this study was to investigate whether the models' age in photographs were automatically detected, even if the photographs were not parts of the ongoing task. Furthermore, we investigated age-related differences, and the possibility of different sensitivity to photographs of participants' own versus different ages. We recorded event-related potentials (ERPs) to faces of young and old models in younger (N = 20; 18-30 years) and older groups (N = 20; 60-75 years). The faces appeared around the location of the field of a tracking task. In sequences the young or the old faces were either frequent (standards) or infrequent (deviants). According to the results, a regular sequence of models' age is automatically registered, and faces violating the models' age elicited the vMMN component. However, in this study vMMN emerged only in the older group to same-age deviants. This finding is explained by the less effective inhibition of irrelevant stimuli in the elderly, and corresponds to own-age bias effect of recognition studies.

A multinomial modelling approach to face identity recognition during instructed threat

To organise future behaviour, it is important to remember both the central and contextual aspects of a situation. We examined the impact of contextual threat or safety, learned through verbal instructions, on face identity recognition. In two studies (N = 140), 72 face-context compounds were presented each once within an encoding session, and an unexpected item/source recognition task was performed afterwards (including 24 new faces). Hierarchical multinomial processing tree modelling served to estimate individual parameters of item (face identity) and source memory (threat or safety context) as well as guessing behaviour. Results show that language was highly effective in establishing threatening and safe context conditions. In Study 1, a fleeting picture stream (1 s per picture) led to poor item and source recognition. Prolonged presentation times (Study 2 with 6 s per picture) improved face memory but no contextual modulation was observed. Thus, incidental face learning was surprisingly poor and rapidly changing contextual settings might have interfered with the accurate encoding of face identity information and item-source binding.

Age biases the judgment rather than the perception of an ambiguous figure

Older participants who are briefly presented with the ‘my wife/mother-in-law’ ambiguous figure estimate its age to be higher than young participants do. This finding is thought to be the result of a subconscious social group bias that influences participants’ perception of the figure. Because people are better able to recognize similarly aged individuals, young participants are expected to perceive the ambiguous figure as a young woman, while older participants are more likely to recognize an older lady. We replicate the difference in age estimates, but find no relationship between participants’ age and their perception of the ambiguous figure. This leads us to conclude that the positive relationship between participants’ age and their age estimates of the ambiguous ‘my wife/mother-in-law’ figure is better explained by the own-age anchor effect, which holds that people use their own age as a yard stick to judge the age of the figure, regardless of whether the young woman or the older lady is perceived. Our results disqualify the original finding as an example of cognitive penetrability: the participants’ age biases their judgment of the ambiguous figure, not its perception.

Recognition of younger and older faces in Korsakoff's syndrome

The own-age bias refers to the observation that face recognition is typically superior for own-age faces compared with other-age faces. We investigated this bias in Korsakoff patients, as well as its relationship with social contact and episodic memory. Korsakoff patients and age-matched controls were exposed to older faces (own-age faces) and younger faces (other-age faces). In the recognition phase, they were invited to decide whether faces had been exposed in the encoding phase or not. Results revealed an own-age bias in control participants (i.e., high recognition of older than for younger faces), but not in Korsakoff patients (i.e., similar recognition of older and younger faces). Furthermore, both Korsakoff's syndrome and controls reported more social contact with old than with young individuals. Recognition of younger and older faces in Korsakoff patients was significantly correlated with episodic performance but not with social contact with younger and older people. We conclude that the lack of own-age bias in Korsakoff's syndrome is related rather to compromise of episodic memory than to diminished social contact with younger adults.

Asymmetric contextual effects in age perception

Perception is context dependent. For example, the perceived orientation of a bar changes depending on the presence of oriented bars around it. Contextual effects have also been demonstrated for more complex judgements, such as facial attractiveness or expression, although it remains unclear how these contextual facial effects depend on the types of faces surrounding the target face. To examine this, we measured the perceived age (a quantifiable measure) of a target face in the presence of differently aged faces in the surround. Using a unique database of standardized passport photos, participants were asked to estimate the age of a target face which was viewed either on its own or surrounded by two different identity flanker faces. The flanker faces were either both younger or both older than the target face, with different age offsets between flankers and targets of ±5, ±10, ±15, ±20 years. We find that when a target face is surrounded by younger faces, it systematically appears younger than when viewed on its own, and when it is surrounded by older faces, it systematically appears older than when viewed on its own. Surprisingly, we find that the magnitude of the flanker effects on perceived age of the target is asymmetric with younger flankers having a greater influence than older flankers, a result that may reflect the participants' own-age bias, since all participants were young. This result holds irrespective of gender or race of the faces and is consistent with averaging.

Neural target selection as a marker of real-world familiarity during search for perceptually distinct objects

Prior studies have shown that behavioral performance is better when detecting specific familiar items based on real-world experience (e.g., an own-age face, a specific bird for bird experts), compared to less familiar items (e.g., an other-age face). These biases emerge from exposure to and interactions with initially less familiar items, which allow for better discrimination and search (e.g., finding an other-age face in a crowd). However, many broad categories in the natural environment (e.g., vintage objects, exotic fruit) contain perceptually distinct items that people can accurately search for individually, even if the objects are not as familiar. How might real-world familiarity impact search in these cases? Recent studies suggest that the N2pc event-related potential (ERP, neural marker of target selection) may be more sensitive than behavioral performance in reflecting prior knowledge, and perhaps familiarity, during visual search. In two experiments, the present study investigated the behavioral effects (Experiment 1) and N2pc effects (Experiment 2) of searching for distinct familiar (modern) versus less familiar (vintage) objects in younger adults. Experiment 1 also included a sample of older adults, who were familiar with both types of objects. Overall, the behavioral results did not reveal robust differences in searching for modern versus vintage objects. However, the N2pc in younger adults was present when searching for modern objects, but not for vintage objects. The N2pc results suggest that this neural marker may be more sensitive than behavioral measures in reflecting familiarity from real-world experiences with object categories.

Stable middle-aged face recognition: No moderation of the own-age bias across contexts

The own-age bias (OAB) has been proposed to be caused by perceptual expertise and/or social-cognitive mechanisms. Investigations into the role of social cognition have, however, yielded mixed results. One reason for this might be the tendency for research to focus on the OAB in young adults, between young and older adult faces where other-age individuation experience is low. To explore whether social-cognitive manipulations may be successful when observers have sufficient other-age individuation experience, we examined biases involving middle-aged other-age faces and the influence of a context manipulation. Across four experiments, young adult participants were presented with middle-aged faces alongside young or older adult faces to remember. We predicted that in contexts where middle-aged faces were positioned as other-age faces (alongside young adult faces), recognition performance would be worse than when they were positioned as relative own-age faces (alongside older adult faces). However, the context manipulations did not moderate middle age face recognition. This suggests that past findings that context does not change other-age face recognition holds for other-age faces for which observers have higher individuation experience. These findings are consistent with a perceptual expertise account of the OAB but more investigation of the generality of these results is required.

Effects of age and mood on emotional face processing differ depending on the intensity of the facial expression

Research suggests that mood can moderate age differences in recognizing facial emotion. In this study, we examined how an anxious versus calm mood state affected younger and older adults' processing of emotional faces. Older adults had greater difficulty identifying negative emotions, particularly when emotions were displayed at a low intensity level. However, an anxious mood did not affect age differences in emotional face recognition. In contrast, age, emotional intensity, and current mood state all affected the perceived intensity of emotion. The effects of age and mood on perceived emotional intensity were only observed for low intensity facial expressions. When induced into an anxious mood, younger adults perceived threatening emotions (i.e., fear, anger) as more emotionally intense, whereas older adults perceived anger and happiness to be more intense. These findings emphasize the need to consider both internal and external factors when investigating the effects of age on emotional face processing.

Evidence of an Own-Age Bias in Facial Emotion Recognition for Adolescents With and Without Autism Spectrum Disorder

A common interpretation of the face-processing deficits associated with autism spectrum disorder (ASD) is that they arise from a failure to develop normative levels of perceptual expertise. One indicator of perceptual expertise for faces is the own-age bias, operationalized as a processing advantage for faces of one's own age, presumably due to more frequent contact and experience. This effect is especially evident in domains of face recognition memory but less commonly investigated in social-emotional expertise (e.g., facial emotion recognition; FER), where individuals with ASD have shown consistent deficits. In the present study, we investigated whether a FER task would elicit an own-age bias for individuals with and without ASD and explored how the magnitude of an own-age bias may differ as a function of ASD status and symptoms. Ninety-two adolescents (63 male) between the ages of 11 and 14 years completed the child- and adult-face subtests of a standardized FER task. Overall FER accuracy was found to differ by ASD severity, reflecting poorer performance for those with increased symptoms. Results also indicated that an own-age bias was evident, reflecting greater FER performance for child compared to adult faces, for all adolescents regardless of ASD status or symptoms. However, the strength of the observed own-age bias did not differ by ASD status or severity. Findings suggest that face processing abilities of adolescents with ASD may be influenced by experience with specific categories of stimuli, similar to their typically developing peers.

Factors that affect younger and older adults' causal attributions of robot behaviour

Stereotypes are cognitive shortcuts that facilitate efficient social judgments about others. Just as causal attributions affect perceptions of people, they may similarly affect perceptions of technology, particularly anthropomorphic technology such as robots. In a scenario-based study, younger and older adults judged the performance and capability of an anthropomorphised robot that appeared young or old. In some cases, the robot successfully performed a task while at other times it failed. Results showed that older adult participants were more susceptible to aging stereotypes as indicated by trust. In addition, both younger and older adult participants succumbed to aging stereotypes when measuring perceived capability of the robots. Finally, a summary of causal reasoning results showed that our participants may have applied aging stereotypes to older-appearing robots: they were most likely to give credit to a properly functioning robot when it appeared young and performed a cognitive task. Our results tentatively suggest that human theories of social cognition do not wholly translate to technology-based contexts and that future work may elaborate on these findings. Practitioner summary: Perception and expectations of the capabilities of robots may influence whether users accept and use them, especially older users. The current results suggest that care must be taken in the design of these robots as users may stereotype them.

Age-related changes in amplitude, latency and specialization of ERP responses to faces and watches

Healthy aging is associated with impairments in face recognition. While earlier research suggests that these impairments arise during memory retrieval, more recent findings suggest that earlier mechanisms, at the perceptual stage, may also be at play. However, results are often inconsistent and very few studies have included a non-face control stimulus to facilitate interpretation of results with respect to the implication of specialized face mechanisms vs. general cognitive factors. To address these issues, P100, N170 and P200 event-related potentials (ERPs) were measured during processing of faces and watches. For faces, age-related differences were found for P100, N170 and P200 ERPs. For watches, age-related differences were found for N170 and P200 ERPs. Older adults showed less selective and less lateralized N170 responses to faces, suggesting that ERPs can detect age-related de-differentiation of specialized face networks. We conclude that age-related impairments in face recognition arise in part from difficulties in the earliest perceptual stages of visual information processing. A working model is presented based on coarse-to-fine analysis of visually similar exemplars.

An own-age bias in mixed- and pure-list presentations: No evidence for the social-cognitive account

The own-age bias (OAB) is suggested to be caused by perceptual-expertise and/or social-cognitive mechanisms. Bryce and Dodson (2013, Psychology and Aging, 28, 87, Exp 2) provided support for the social-cognitive account, demonstrating an OAB for participants who encountered a mixed-list of own- and other-age faces, but not for participants who encountered a pure-list of only own- or other-age faces. They proposed that own-age/other-age categorization, and the resulting OAB, only emerge when age is made salient in the mixed-list condition. Our study aimed to replicate this finding using methods typically used to investigate the OAB to examine their robustness and contribution to our understanding of how the OAB forms. Across three experiments that removed theoretically unimportant components of the original paradigm, varied face sex, and included background scenes, the OAB emerged under both mixed-list and pure-list conditions. These results are more consistent with a perceptual-expertise than social-cognitive account of the OAB, but may suggest that manipulating age salience using mixed-list and pure-list presentations is not sufficient to alter categorization processes.

An event-related potential investigation of age and sex in face categorization: Participant sex matters

Whether a face is categorized as male or female is influenced by the age of the face. In the present study, Event-Related Potential (ERP) measures were employed to offer insight into the neural correlates indexing the interaction between the age and sex of a face during sex categorization. Thirty-eight young adults (18 male) categorized the sex of young (18-29 years) and older (70-94 years) adult faces as ERP activity was recorded. Amplitude modulation for the P3b was observed in parietal regions. Younger female faces elicited more positive P3b amplitudes than older female faces, a difference that did not occur for male faces. Behavioral performance and P3b modulation also indicated these effects varied between male and female participants. Women responded more slowly and with less accuracy to older female faces compared to male and young female faces, a pattern of results mirrored by P3b latency. These findings indicate that later-occurring ERP components, such as the P3b, signal the intersection of multiple social categories during face processing suggesting that the evaluation of ingroup/outgroup membership related to age is enhanced for young women, but not for young men.

Amygdala functional network during recognition of own-age vs. other-age faces in younger and older adults

Facial cues, such as a person's age, provide important information for social interactions. Processing such facial cues can be affected by observer bias. However, there is currently no consensus regarding how the brain is processing facial cues related to age, and if facial age processing changes as a function of the age of the observer (i.e., own-age bias). The primary study aim was to investigate functional networks involved in processing own-age vs. other-age faces among younger and older adults and determine how emotional expression of the face modulates own-age vs. other-age face processing. The secondary study aim was to examine the relation between higher social cognitive processes (i.e., empathy) and modulation of brain activity by facial age and emotional expression. During functional magnetic resonance imaging (fMRI) younger and older participants were asked to recognize happy, angry, and neutral expressions in own-age and other-age faces. Functional connectivity analyses with the amygdala as seed showed that for own-age faces both age groups recruited a network of regions including the anterior cingulate and anterior insula that was involved in empathy and detection of salient information. Brain-behavior analyses furthermore showed that empathic responses in younger, but not in older, participants were positively correlated with engagement of the medial prefrontal cortex during processing of angry own-age faces. These findings identify the neurobehavioral correlates of facial age processing, and its modulation by emotion expression, and directly link facial cue processing to higher-order social cognitive functioning.

No Own-Age Bias in Children's Gaze-Cueing Effects

Sensitivity to another person's eye gaze is vital for social and language development. In this eye-tracking study, a group of 74 children (6-14 years old) performed a gaze-cueing experiment in which another person's shift in eye gaze potentially cued the location of a peripheral target. The aim of the present study is to investigate whether children's gaze-cueing effects are modulated by the other person's age. In half of the trials, the gaze cue was given by adult models, in the other half of the trials by child models. Regardless of the models' ages, children displayed an overall gaze-cueing effect. However, results showed no indication of an own-age bias in the performance on the gaze-cueing task; the gaze-cueing effect is similar for both child and adult face cues. These results did not change when we looked at the performance of a subsample of participants (n = 23) who closely matched the age of the child models. Our results do not allow us to disentangle the possibility that children are insensitive to a model's age or whether they consider models of either age as equally informative. Future research should aim at trying to disentangle these two possibilities.

Own-Age Bias and Positivity Effects in Facial Recognition

Background/Study Context - In the current study, we evaluated two age-related differences in recognition memory: the own-age bias, wherein older and younger adults best recognize those of their own age group, and an age-related positivity effect, wherein older adults recall positive emotional information better than negative information relative to younger adults. We sought to extend previous research that jointly investigated these variables in recognition memory. Methods - Younger (age 18 - 27) and older (age 62 - 80) adults completed an incidental encoding task on a sequence of 50 positive, negative, or neutrally valenced images of older and younger adult faces. After a distractor task, participants made forced-choice recognition judgments and rated their decision confidence for images that were repeated with the same or a different emotional expression, and for novel, previously unseen faces. Results - Older and younger adults' recognition discriminability did not differ significantly between age groups. Notably, the data indicated an own-age bias in young adults, but not in older adults, and both age groups' recognition accuracy was greatest for faces that had originally been shown with a positive emotional expression. Conclusion - To our knowledge, this research is the first to demonstrate an own-age recognition bias in younger adults for emotional faces. Although our predictions of a differential impact by emotional faces on recognition of same and other-age faces were not supported, we identify a number of factors that contextualize these findings in the recent literature.

Perception of an ambiguous figure is affected by own-age social biases

Although the perception of faces depends on low-level neuronal processes, it is also affected by high-level social processes. Faces from a social in-group, such as people of a similar age, receive more in-depth processing and are processed holistically. To explore whether own-age biases affect subconscious face perception, we presented participants with the young/old lady ambiguous figure. Mechanical Turk was used to sample participants of varying ages from the USA. Results demonstrated that younger and older participants estimated the age of the image as younger and older, respectively. This own-age effect ties in with socio-cultural practices, which are less inclusive towards the elderly. Participants were not aware the study was related to ageing and the stimulus was shown briefly. The results therefore demonstrate that high-level social group processes have a subconscious effect on the early stages of face processing. A neural feedback model is used to explain this interaction.

Electrophysiological correlates of voice memory for young and old speakers in young and old listeners

Faces of one's own-age group are easier to recognize than other-age faces. Using behavioral measures and EEG, we studied whether an own-age bias (OAB) also exists in voice memory. Young (19 - 26 years) and old (60-75 years) participants studied young (18-25 years) and old (60-77 years) unfamiliar voices from short sentences. Subsequently, they classified studied and novel voices as "old" (i.e. studied) or "new", from the same sentences. Recognition performance was higher in young compared to old participants, and for old compared to young voices, with no OAB. At the same time, we found evidence for higher distinctiveness of old compared to young voices, both in terms of acoustic measures and subjective ratings (independent of rater age). Analyses of event-related brain potentials (ERPs) indicated more negative-going deflections (400-1000ms) for old compared to young voices in young participants. In old participants, we observed a reversed OLD/NEW memory effect, with overall more positive amplitudes for novel compared to studied old (but not young) voices (400-1000ms). Time-frequency analyses revealed less beta power (16-26Hz) for young compared to old voices at left anterior sites, and also reduced beta power for correctly recognized studied (compared to novel) voices at left posterior sites (300-900ms). These findings could suggest an engagement of cortical areas during stimulus-specific recollection from about 300ms, in a task that emphasized the analysis of individual acoustic features.

The relationship between visual search and categorization of own- and other-age faces

Young adult participants are faster to detect young adult faces in crowds of infant and child faces than vice versa. These findings have been interpreted as evidence for more efficient attentional capture by own-age than other-age faces, but could alternatively reflect faster rejection of other-age than own-age distractors, consistent with the previously reported other-age categorization advantage: faster categorization of other-age than own-age faces. Participants searched for own-age faces in other-age backgrounds or vice versa. Extending the finding to different other-age groups, young adult participants were faster to detect young adult faces in both early adolescent (Experiment 1) and older adult backgrounds (Experiment 2). To investigate whether the own-age detection advantage could be explained by faster categorization and rejection of other-age background faces, participants in experiments 3 and 4 also completed an age categorization task. Relatively faster categorization of other-age faces was related to relatively faster search through other-age backgrounds on target absent trials but not target present trials. These results confirm that other-age faces are more quickly categorized and searched through and that categorization and search processes are related; however, this correlational approach could not confirm or reject the contribution of background face processing to the own-age detection advantage.

Validation of the Vanderbilt Holistic Face Processing Test

The Vanderbilt Holistic Face Processing Test (VHPT-F) is a new measure of holistic face processing with better psychometric properties relative to prior measures developed for group studies (Richler et al., 2014). In fields where psychologists study individual differences, validation studies are commonplace and the concurrent validity of a new measure is established by comparing it to an older measure with established validity. We follow this approach and test whether the VHPT-F measures the same construct as the composite task, which is group-based measure at the center of the large literature on holistic face processing. In Experiment 1, we found a significant correlation between holistic processing measured in the VHPT-F and the composite task. Although this correlation was small, it was comparable to the correlation between holistic processing measured in the composite task with the same faces, but different target parts (top or bottom), which represents a reasonable upper limit for correlations between the composite task and another measure of holistic processing. These results confirm the validity of the VHPT-F by demonstrating shared variance with another measure of holistic processing based on the same operational definition. These results were replicated in Experiment 2, but only when the demographic profile of our sample matched that of Experiment 1.

The characteristics of social categorization based on the unidimensional variation of gender versus age

The present study explored the characteristics of social categorization based on the unidimensional variation of gender or age using the Garner's Selective Attention Paradigm. The task of the experiment was to judge whether there was a mole on a person's face, and the results showed that young participants' response times were slower when the age or gender of the face stimuli varied, demonstrating that young people, rather than older people, can activate both an age category and a gender category automatically. Meanwhile, all participants' responses to the old faces were slower than that to the young faces. Females reacted faster than males, demonstrating that females tend to have an advantage for face processing.

Perceptual and Social Attributes Underlining Age-Related Preferences for Faces

Although aesthetic preferences are known to be important in person perception and can play a significant role in everyday social decisions, the effect of the age of the observer on aesthetic preferences for faces of different ages has not yet been fully investigated. In the present study we investigated whether aesthetic preferences change with aging, with an age-related bias in favoring faces from one’s own age group. In addition, we examined the role of age on both the perceptual qualities and the social attributes of faces that may influence these aesthetic judgements. Both younger and older adult observers provided ratings to images of younger, middle-aged and older unfamiliar faces. As well as attractiveness, the rating dimensions included other perceptual (distinctiveness, familiarity) and social (competence, trustworthiness and dominance) factors. The results suggested a consistent aesthetic preference for youthful faces across all ages of the observers but, surprisingly, no evidence for an age-related bias in attractiveness ratings. Older adults tended to provide higher ratings of attractiveness, competence and trustworthiness to the unfamiliar faces, consistent with the positivity effect previously reported. We also tested whether perceptual factors such as face familiarity or distinctiveness affected aesthetic ratings. Only ratings of familiarity, but not distinctiveness, were positively associated with the attractiveness of the faces. Moreover, ratings of familiarity decreased with increasing age of the face. With regard to the social characteristics of the faces, we found that the age of the face negatively correlated with ratings of trustworthiness provided by all observers, but with the competence ratings of older observers only. Interestingly, older adults provided higher ratings of perceived competence and trustworthiness to younger than older faces. However, our results also suggest that higher attractiveness ratings, together with older aged faces, led to more positive evaluations of competence. The results are discussed within the context of an age-related decline in the differentiation of faces in memory. Our findings have important implications for a better understanding of age-related perceptual factors and cognitive determinants of social interactions with unfamiliar others across the adult lifespan.

The infamous among us: Enhanced reputational memory for uncooperative ingroup members

People remember uncooperative individuals better than cooperative ones. We hypothesize that this is particularly true when uncooperative individuals belong to one's ingroup, as their behavior violates positive expectations. Two studies examined the effect of minimal group categorization on reputational memory of the social behavior of particular ingroup and outgroup members. We manipulated uncooperative behavior as the unfair sharing of resources with ingroup members (Study 1), or as descriptions of cheating (Study 2). Participants evaluated several uncooperative and cooperative (and neutral) ingroup and outgroup members. In a surprise memory test, they had to recognize target faces and recall their behavior. We disentangled face recognition, reputational memory, and guessing biases with multinomial models of source monitoring. The results show enhanced reputational memory for uncooperative ingroup members, but not uncooperative outgroup members. In contrast, guessing behavior indicated that participants assumed more ingroup cooperation than outgroup cooperation. Our findings integrate prior research on memory for uncooperative person behavior and person memory in group contexts. We suggest that the ability to remember the uncooperative amidst the supposedly cooperative ingroup could stabilize intragroup cooperation.

Judging Normality and Attractiveness in Faces: Direct Evidence of a More Refined Representation for Own-Race, Young Adult Faces

Young and older adults are more sensitive to deviations from normality in young than older adult faces, suggesting that the dimensions of face space are optimized for young adult faces. Here, we extend these findings to own-race faces and provide converging evidence using an attractiveness rating task. In Experiment 1, Caucasian and Chinese adults were shown own- and other-race face pairs; one member was undistorted and the other had compressed or expanded features. Participants indicated which member of each pair was more normal (a task that requires referencing a norm) and which was more expanded (a task that simply requires discrimination). Participants showed an own-race advantage in the normality task but not the discrimination task. In Experiment 2, participants rated the facial attractiveness of own- and other-race faces (Experiment 2a) or young and older adult faces (Experiment 2b). Between-rater variability in ratings of individual faces was higher for other-race and older adult faces; reduced consensus in attractiveness judgments reflects a less refined face space. Collectively, these results provide direct evidence that the dimensions of face space are optimized for own-race and young adult faces, which may underlie face race- and age-based deficits in recognition.

ERP evidence for own-age effects on late stages of processing sad faces

Faces convey important information on interaction partners, such as their emotional state and age. Faces of the same age are, according to recent research, preferentially processed. The aim of the present study was to investigate whether the neural processes underlying this own-age effect are influenced by the emotional expression of the face, and to explore possible explanations such as the frequency or quality of contact to own-age versus other-age groups. Event-related potentials were recorded while 19 younger (18-30 years) and 19 older (64-86 years) observers watched younger and older sad and happy faces. Sad but not happy faces elicited higher late positive potential amplitudes for own-age than for other-age faces. This own-age effect was significant for older, but not for younger, observers, and correlated with the quality of contact with the own-age versus the other-age group. This pattern suggests that sad own-age faces are motivationally more relevant.

Children view own-age faces qualitatively differently to other-age faces

Like most own-group biases in face recognition, the own-age bias (OAB) is thought to be based either on perceptual expertise or socio-cognitive motivational mechanisms [Wolff, N., Kemter, K., Schweinberger, S. R., & Wiese, H. (2013). What drives social in-group biases in face recognition memory? ERP evidence from the own-gender bias. Social Cognitive and Affective Neuroscience. doi:10.1093/scan/nst024]. The present study employed a recognition paradigm with eye-tracking in order to assess whether participants actively viewed faces of their own-age differently to that of other-age faces. The results indicated a significant OAB (superior recognition for own-age relative to other-age faces), provided that they were upright, indicative of expertise being employed for the recognition of own-age faces. However, the eye-tracking results indicate that viewing other-age faces was qualitatively different to the viewing of own-age faces, with more nose fixations for other-age faces. These results are interpreted as supporting the socio-cognitive model of the OAB.

Guidelines for studying developmental prosopagnosia in adults and children

Developmental prosopagnosia (DP) is a neurodevelopmental condition characterized by severe face identity recognition problems that results from a failure to develop the mechanisms necessary for adequate face processing (Duchaine BC, Nakayama K. Developmental prosopagnosia: a window to content-specific face processing. Curr Opin Neurobiol 2006, 16:166-173.). It occurs in children and adults with normal visual acuity, and without intellectual impairments or known brain injuries. Given the importance of face recognition in daily life, and the detrimental effects of impaired face recognition, DP is an important area of study. Yet conventions for classifying individuals as DP for research purposes are poorly defined. In this focus paper, we discuss: (1) criteria for an operational definition of DP; 2) tests of face recognition and conventions for classifying individuals as DP; and 3) important considerations regarding common associations and dissociations, and cognitive heterogeneity in DP. We also highlight issues unique to studying DP in children, a relatively new endeavor that is proving to be an important complement to the work with adults. Ultimately, we hope to identify challenges researchers face when studying DP, and offer guidelines for others to consider when embarking on their own research pursuits on the topic. For further resources related to this article, please visit the WIREs website.

Visual scanning behavior is related to recognition performance for own- and other-age faces

It is well-established that our recognition ability is enhanced for faces belonging to familiar categories, such as own-race faces and own-age faces. Recent evidence suggests that, for race, the recognition bias is also accompanied by different visual scanning strategies for own- compared to other-race faces. Here, we tested the hypothesis that these differences in visual scanning patterns extend also to the comparison between own and other-age faces and contribute to the own-age recognition advantage. Participants (young adults with limited experience with infants) were tested in an old/new recognition memory task where they encoded and subsequently recognized a series of adult and infant faces while their eye movements were recorded. Consistent with findings on the other-race bias, we found evidence of an own-age bias in recognition which was accompanied by differential scanning patterns, and consequently differential encoding strategies, for own-compared to other-age faces. Gaze patterns for own-age faces involved a more dynamic sampling of the internal features and longer viewing time on the eye region compared to the other regions of the face. This latter strategy was extensively employed during learning (vs. recognition) and was positively correlated to discriminability. These results suggest that deeply encoding the eye region is functional for recognition and that the own-age bias is evident not only in differential recognition performance, but also in the employment of different sampling strategies found to be effective for accurate recognition.