Infants' top-down perceptual modulation is specific to own-race faces.

Recent studies have revealed the influence of higher-level cognitive systems in modulating perceptual processing (top-down perceptual modulation) in infancy. However, more research is needed to understand how top-down processes in infant perception contribute to early perceptual development. To this end, this study examined infants' top-down perception of own- and other-race faces to reveal whether top-down modulation is linked to the emergence of perceptual specialization. Infants first learned an association between a sound and faces, with the race of the faces manipulated between groups (own race vs. other race). We then tested infants' face perception across various levels of perceptual difficulty (manipulated by presentation duration) and indexed top-down perception by the change in perception when infants heard the sound previously associated with the face (predictive sound) versus an irrelevant sound. Infants exhibited top-down face perception for own-race faces (Experiment 1). However, we present new evidence that infants did not show evidence of top-down modulation for other-race faces (Experiment 2), suggesting an experience-based specificity of this capacity with more effective top-down modulation in familiar perceptual contexts. In addition, we ruled out the possibility that this face race effect was due to differences in infants' associative learning of the sound and faces between the two groups. This work has important implications for understanding the mechanisms supporting perceptual development and how they relate to top-down perception in infancy.

Facial dominance augments perceived proximity: Evidence from a visual illusion.

Dominance is a major organizing principle of human societies that impacts a wide range of human behaviors, from gaze-following to voting choices. Here, we examined how dominance modulates a fundamental perceptual ability: the perception of proximity. We used the "Fat Face" illusion, a novel paradigm that measures perceived proximity implicitly. The illusion depicts a phenomenon that occurs when two identical faces are aligned vertically (one above the other) and the bottom face consistently appears larger. This illusion suggests that our visual system uses a vertical layout to infer the relative proximity of faces, so that the bottom face appears closer, and is thereby perceived as larger than the top one. We found that the illusion was larger for dominant than for submissive faces (Experiment 1). Moreover, when a dominant face was presented below a submissive one, participants reported a larger illusion than when a dominant face was above a submissive face (Experiments 2a and 2b). These findings suggest that dominant faces are perceived to be closer to observers than submissive faces. Furthermore, we found a stronger illusion for other-race faces as opposed to own-race faces, suggesting that we also misperceive other-race faces as closer than own-race faces. Together, these findings suggest that the visual system is highly sensitive to self-relevant, potentially threatening stimuli (e.g., dominant faces and other-race individuals) in the environment by misperceiving them as closer. In line with the recently proposed threat-signal hypothesis, this mechanism may allow for rapid and adaptive behaviors in our everyday social interactions. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Visual Perception Is Highly Flexible and Context Dependent in Young Infants: A Case of Top-Down-Modulated Motion Perception.

Top-down modulation is an essential cognitive component in human perception. Despite mounting evidence of top-down perceptual modulation in adults, it is largely unknown whether infants can engage in this cognitive function. Here, we examined top-down modulation of motion perception in 6- to 8-month-old infants (recruited in North America) via their smooth-pursuit eye movements. In four experiments, we demonstrated that infants' perception of motion direction can be flexibly shaped by briefly learned predictive cues when no coherent motion is available. The current findings present a novel insight into infant perception and its development: Infant perceptual systems respond to predictive signals engendered from higher-level learning systems, leading to a flexible and context-dependent modulation of perception. This work also suggests that the infant brain is sophisticated, interconnected, and active when placed in a context in which it can learn and predict.

Face recognition ability can be predicted by microstructural properties of white matter: a study of diffusion tensor imaging (DTI).

There is a great individual difference in people's face recognition ability (FRA). This study aimed to reveal the neural mechanism underlying such individual differences. Elastic-net regression models were constructed to predict FRA based on the white matter (WM) microstructural properties. We found that FRA can be accurately predicted by the WM microstructural properties. For the right inferior longitudinal fasciculus (ILF) and bilateral arcuate fasciculus (AF), FRA was correlated negatively to fractional anisotropy (FA), but positively to radial diffusivity (RD). In contrast, for the corpus callosum forceps minor (CFM), FRA was correlated positively to FA, but negatively to RD. Such various patterns of the WM microstructural properties suggested a positive correlation between FRA and fiber diameter for the right ILF and bilateral AF, but a negative correlation between FRA and diameter of the CFM. These findings reflected that FRA was correlated positively to connectivities of the right ILF and bilateral AF, but negatively to those of the CFM. These findings not only confirmed the significant role of the right ILF in face recognition, but also revealed the involvement of the bilateral AF and CFM in face recognition, particularly implying the important role of hemisphere lateralization modulated by transcallosal connectivity in face recognition.

The discrimination of expressions in facial movements by infants: A study with point-light displays.

Perceiving facial expressions is an essential ability for infants. Although previous studies indicated that infants could perceive emotion from expressive facial movements, the developmental change of this ability remains largely unknown. To exclusively examine infants' processing of facial movements, we used point-light displays (PLDs) to present emotionally expressive facial movements. Specifically, we used a habituation and visual paired comparison (VPC) paradigm to investigate whether 3-, 6-, and 9-month-olds could discriminate between happy and fear PLDs after being habituated with a happy PLD (happy-habituation condition) or a fear PLD (fear-habituation condition). The 3-month-olds discriminated between the happy and fear PLDs in both the happy- and fear-habituation conditions. The 6- and 9-month-olds showed discrimination only in the happy-habituation condition but not in the fear-habituation condition. These results indicated a developmental change in processing expressive facial movements. Younger infants tended to process low-level motion signals regardless of the depicted emotions, and older infants tended to process expressions, which emerged in familiar facial expressions (e.g., happy). Additional analyses of individual difference and eye movement patterns supported this conclusion. In Experiment 2, we concluded that the findings of Experiment 1 were not due to a spontaneous preference for fear PLDs. Using inverted PLDs, Experiment 3 further suggested that 3-month-olds have already perceived PLDs as face-like stimuli.

The "Fat Face" illusion: A robust adaptation for processing pairs of faces.

Converging evidence has demonstrated our remarkable capacities to process individual faces. However, in real-life contexts, we rarely see faces in isolation. It is largely unknown how our visual system processes a multitude of faces. The current study explored this question by using the "Fat Face" illusion: when two identical faces are vertically aligned, the bottom face appears bigger. In Experiment 1, we tested the robustness of this illusion by using faces varied by gender and race, by recruiting participants from different countries (Canadian, Chinese, and French), and by implementing different task requirements. We found that the illusion was stable and immune to variations in face gender or face race, perceptual familiarity, and task requirements. Experiment 2 further indicated that binocular vision was essential for this visual illusion. When participants performed the task with one eye covered, the previously robust illusion completely disappeared. Together, these findings revealed a visual adaptation for processing multiple faces in the environment: the face at the top is perceived as more distant from the viewer and appears smaller in size than the face at the bottom. More broadly, overestimating the size of the bottom face may represent a fundamental mechanism for social interactions, ensuring the deployment of attention to those closest to self.

Emotional expressions reinstate recognition of other-race faces in infants following perceptual narrowing.

Perceptual narrowing occurs in human infants for other-race faces. A paired-comparison task measuring infant looking time was used to investigate the hypothesis that adding emotional expressiveness to other-race faces would help infants break through narrowing and reinstate other-race face recognition. Experiment 1 demonstrated narrowing for White infants viewing neutral Asian faces: whereas 3-month-olds differentiated Asian faces, 6-month-olds did not. Experiment 2 showed that White 6-month-olds differentiated the same Asian faces depicted with angry or happy expressions. Experiments 3 and 4 yielded comparable results for 6- and 9-month-olds tested with Black faces (i.e., narrowing with neutral faces, reinstatement of sensitivity when the faces were presented with emotion). Experiment 5 showed that White 6-month-olds did not differentiate inverted angry or happy Asian faces, and that White 9-month-olds did not differentiate inverted angry or happy Black faces. Looking time during familiarization did not differ for upright neutral and emotional faces, indicating that the expressions did not yield more salient stimuli. Also, consistent with the inversion findings, analyses of the low-level image properties as well as equivalent pairwise similarity ratings obtained from White adults for the neutral and emotional faces indicated that the expressions did not simply create more discriminable stimuli. Without support for the lower-level accounts, we discuss the possibility that the infants processed the communicative intent of the expressions. Because angry faces pose threat and happy faces invite affiliation, expression may create motivation to individuate. Overall, the data suggest that early perceptual-social linkage in face representation can arise via a social-to-perceptual pathway. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Infants use knowledge of emotions to augment face perception: Evidence of top-down modulation of perception early in life.

While top-down modulation is believed to be central to adult perception, the developmental origins of this ability are unclear. Here, we present a direct, behavioral investigation of top-down modulation of perception in infancy using emotional face perception as a test case. We investigated whether 9-month-olds can modulate their face perception based on predictive, auditory emotional cues without any training or familiarization procedure. Infants first heard a 3-second emotional vocal sound (happy/angry) while their gaze was held in the center of the screen. Then, they were presented with a pair of emotional and neutral faces images without any audio sound. The faces were small (4.70° × 5.80°) and presented in randomized locations outside their focus of attention. We measured the initial latency to shift gaze to look at a congruent emotional face as an index of infants' pre-attentive perception of these faces. We found that infants' face perception was augmented by preceding emotional cues: They were faster to look at the emotional face after hearing an emotionally congruent sound than an incongruent one. Moreover, the emotional sounds boosted perception of congruent faces 200 ms after the onset of the faces. These top-down effects were robust for both happy and angry emotions, indicating a flexible and active control of perception based on different top-down cues. A control study further supported the view that the Congruency effect is due to a top-down influence on face perception rather than a rapid matching of cross-modal emotional signals. Together, these findings demonstrate that top-down modulation of perception is already quite sophisticated early in development. Raw data is available on Github (https://github.com/naiqixiao/CuedEmotion.git).

Monolingual but not bilingual infants demonstrate racial bias in social cue use.

Bilingualism exerts early and pervasive effects on cognition, observable in infancy. Thus far, investigations of infant bilingual cognition have focused on sensitivity to visual memory, executive function, and linguistic sensitivity. Much less research has focused on how bilingualism impacts processing of social cues. The present study sought to investigate whether bilingualism modulates the expression of one aspect of social processing: early racial bias. Using a gaze-following paradigm, we investigated whether 18- to 20-month-old monolingual and bilingual infants favored their own race. Results demonstrated that monolingual infants favored their own race in following a model whose direction of gaze signaled an event. In contrast, bilingual infants demonstrated race-neutral gaze-following patterns, relying more heavily on the reliability of the behavior of the model over race. Findings suggest that bilingualism may have protective effects against the early emergence of racial bias.

Narrowing in face and speech perception in infancy: Developmental change in the relations between domains.

Although prior research has established that perceptual narrowing reflects the influence of experience on the development of face and speech processing, it is unclear whether narrowing in the two domains is related. A within-participant design (N = 72) was used to investigate discrimination of own- and other-race faces and native and non-native speech sounds in 3-, 6-, 9-, and 12-month-old infants. For face and speech discrimination, whereas 3-month-olds discriminated own-race faces and native speech sounds as well as other-race faces and non-native speech sounds, older infants discriminated only own-race faces and native speech sounds. Narrowing in face and narrowing in speech were not correlated at 6 months, negatively correlated at 9 months, and positively correlated at 12 months. The findings reveal dynamic developmental changes in the relation between modalities during the first year of life.

The Fusiform Face Area Plays a Greater Role in Holistic Processing for Own-Race Faces Than Other-Race Faces.

Own-race faces are recognized more effectively than other-race faces. This phenomenon is referred to as other-race effect (ORE). Existing behavioral evidence suggests that one of the possible causes of ORE is that own-race faces are processed more holistically than other-race faces. However, little is known about whether such differences in processing also produce distinctive neural responses in the cortical face processing network. To bridge this gap, the present study used fMRI methodology and the composite face paradigm to examine the response patterns of the traditional face-preferential cortical areas (i.e., the bilateral fusiform face areas [FFA] and the bilateral occipital face areas [OFA]) elicited by own-race faces and other-race faces. We found that the right FFA exhibited a neural composite face effect only for own-race faces but not for other-race faces, even with the absence of the race-related difference in behavior composite face effect. These findings suggest that the right FFA plays a greater role in holistic processing of individual own-race faces than other-race faces. They also suggest that the neural composite effect observed in the right FFA is not the exact neural counterpart of the behavioral face composite effect. The findings of the present study revealed that, along the pathway of the bottom-up face processing, own-race faces and other-race faces presented the holistic processing difference as early as when they were processed in the right FFA.

Relations between scanning and recognition of own- and other-race faces in 6- and 9-month-old infants.

Infants typically see more own-race faces than other-race faces. Existing evidence shows that this difference in face race experience has profound consequences for face processing: as early as 6 months of age, infants scan own- and other-race faces differently and display superior recognition for own- relative to other-race faces. However, it is unclear whether scanning of own-race faces is related to the own-race recognition advantage in infants. To bridge this gap in the literature, the current study used eye tracking to investigate the relation between own-race face scanning and recognition in 6- and 9-month-old Asian infants (N = 82). The infants were familiarized with dynamic own- and other-race faces, and then their face recognition was tested with static face images. Both age groups recognized own- but not other-race faces. Also, regardless of race, the more infants scanned the eyes of the novel versus familiar faces at test, the better their face-recognition performance. In addition, both 6- and 9-month-olds fixated significantly longer on the nose of own-race faces, and greater fixation on the nose during test trials correlated positively with individual novelty preference scores in the own- but not other-race condition. The results suggest that some aspects of the relation between recognition and scanning are independent of differential experience with face race, whereas other aspects are affected by such experience. More broadly, the findings imply that scanning and recognition may become linked during infancy at least in part through the influence of perceptual experience.

iTemplate: A template-based eye movement data analysis approach.

Current eye movement data analysis methods rely on defining areas of interest (AOIs). Due to the fact that AOIs are created and modified manually, variances in their size, shape, and location are unavoidable. These variances affect not only the consistency of the AOI definitions, but also the validity of the eye movement analyses based on the AOIs. To reduce the variances in AOI creation and modification and achieve a procedure to process eye movement data with high precision and efficiency, we propose a template-based eye movement data analysis method. Using a linear transformation algorithm, this method registers the eye movement data from each individual stimulus to a template. Thus, users only need to create one set of AOIs for the template in order to analyze eye movement data, rather than creating a unique set of AOIs for all individual stimuli. This change greatly reduces the error caused by the variance from manually created AOIs and boosts the efficiency of the data analysis. Furthermore, this method can help researchers prepare eye movement data for some advanced analysis approaches, such as iMap. We have developed software (iTemplate) with a graphic user interface to make this analysis method available to researchers.

Infants Rely More on Gaze Cues From Own-Race Than Other-Race Adults for Learning Under Uncertainty.

Differential experience leads infants to have perceptual processing advantages for own- over other-race faces, but whether this experience has downstream consequences is unknown. Three experiments examined whether 7-month-olds (range = 5.9-8.5 months; N = 96) use gaze from own- versus other-race adults to anticipate events. When gaze predicted an event's occurrence with 100% reliability, 7-month-olds followed both adults equally; with 25% (chance) reliability, neither was followed. However, with 50% (uncertain) reliability, infants followed own- over other-race gaze. Differential face race experience may thus affect how infants use social cues from own- versus other-race adults for learning. Such findings suggest that infants integrate online statistical reliability information with prior knowledge of own versus other race to guide social interaction and learning.

Older but not younger infants associate own-race faces with happy music and other-race faces with sad music.

We used a novel intermodal association task to examine whether infants associate own- and other-race faces with music of different emotional valences. Three- to 9-month-olds saw a series of neutral own- or other-race faces paired with happy or sad musical excerpts. Three- to 6-month-olds did not show any specific association between face race and music. At 9 months, however, infants looked longer at own-race faces paired with happy music than at own-race faces paired with sad music. Nine-month-olds also looked longer at other-race faces paired with sad music than at other-race faces paired with happy music. These results indicate that infants with nearly exclusive own-race face experience develop associations between face race and music emotional valence in the first year of life. The potential implications of such associations for developing racial biases in early childhood are discussed.

Own-Group Face Recognition Bias: The Effects of Location and Reputation.

In the present study, we examined whether social categorization based on university affiliation can induce an advantage in recognizing faces. Moreover, we investigated how the reputation or location of the university affected face recognition performance using an old/new paradigm. We assigned five different university labels to the faces: participants' own university and four other universities. Among the four other university labels, we manipulated the academic reputation and geographical location of these universities relative to the participants' own university. The results showed that an own-group face recognition bias emerged for faces with own-university labels comparing to those with other-university labels. Furthermore, we found a robust own-group face recognition bias only when the other university was located in a different city far away from participants' own university. Interestingly, we failed to find the influence of university reputation on own-group face recognition bias. These results suggest that categorizing a face as a member of one's own university is sufficient to enhance recognition accuracy and the location will play a more important role in the effect of social categorization on face recognition than reputation. The results provide insight into the role of motivational factors underlying the university membership in face perception.

Bilingual Infants Demonstrate Perceptual Flexibility in Phoneme Discrimination but Perceptual Constraint in Face Discrimination.

Perceptual narrowing is a highly significant development associated with the first year of life. It conventionally refers to an orientation toward nativeness whereby infant's perceptual sensitivities begin to align with the phonetic properties of their native environment. Nativeness effects, such as perceptual narrowing, have been observed in several domains, most notably, in face discrimination within other-race faces and speech discrimination of non-native phonemes. Thus, far, nativeness effects in the face and speech perception have been theoretically linked, but have mostly been investigated independently. An important caveat to nativeness effects is that diversifying experiences, such as bilingualism or multiracial exposure, can lead to a reduction or postponement in attunement to the native environment. The present study was designed to investigate whether bilingualism influences nativeness effects in phonetic and face perception. Eleven-month-old monolingual and bilingual infants were tested on their abilities to discriminate native and non-native speech contrasts as well as own-race and other-race face contrasts. While monolingual infants demonstrated nativeness effects in face and speech perception, bilingual infants demonstrated nativeness effects in the face perception but demonstrated flexibility in speech perception. Results support domain-specific effects of bilingual experience on nativeness effects.

An adult face bias in infants that is modulated by face race.

The visual preferences of infants for adult versus infant faces were investigated. Caucasian 3.5- and 6-month-olds were presented with Caucasian adult versus infant face pairs and Asian adult versus infant face pairs, in both upright and inverted orientations. Both age groups showed a visual preference for upright adult over infant faces when the faces were Caucasian, but not when they were Asian. The preference is unlikely to have arisen because of low-level perceptual features because: (1) no preference was observed for the inverted stimuli, (2) no differences were observed in adult similarity ratings of the upright infant-adult face pairs from the two races, and (3) no differences between the infant and adult faces were observed across races in an image-based analysis of salience. The findings are discussed in terms of the social attributes of faces that are learned from experience and what this implies for developmental accounts of a recognition advantage for adult faces in particular and models of face processing more generally.

Facial movements facilitate part-based, not holistic, processing in children, adolescents, and adults.

Although most of the faces we encounter daily are moving ones, much of what we know about face processing and its development is based on studies using static faces that emphasize holistic processing as the hallmark of mature face processing. Here the authors examined the effects of facial movements on face processing developmentally in children (8-year-olds), adolescents (12-year-olds), and adults (20-year-olds). In particular, the composite face effect was used to measure the influence of facial movements on part-based versus holistic processing after participants had viewed either a moving or static face in a within-subject design. Experiment 1 examined elastic facial movement (i.e., blinking and chewing). The results showed that children, adolescents, and adults exhibited a significantly smaller composite effect after viewing a moving face than after viewing a static face. This result indicates that elastic facial movement facilitates part-based face processing from at least 8 years of age onward. Experiment 2 examined rigid facial movement (i.e., head turning) and revealed that it too facilitates part-based face processing in children, adolescents, and adults. The results taken together suggest that contrary to the prevailing view, facial movements facilitate part-based, not holistic, face processing in children, adolescents, and adults. The findings call for revision in the conventional way of thinking about what constitutes the developmental trajectory toward mature face processing and also point to the importance of using more naturalistic moving face stimuli to study face processing and its development. (PsycINFO Database Record

Scanning of own- versus other-race faces in infants from racially diverse or homogenous communities.

We examined the role of community face experience on 6- and 8-month-old Caucasian infants' scanning of own- and other-race face scanning. We measured infants' proportional fixation time and scan path amplitudes as indices of face processing. Proportional fixation time to informationally rich face regions varied as a function of age and face race for infants living in a racially homogeneous community, whereas scan path amplitudes varied as a function of age and face race for infants living in a racially diverse community. In both communities 6-month-old infants did not show different responding to own- and other-race faces, whereas 8-month-old infants responded differently to own- and other-race faces. However, 8-month-old infants from the two communities showed different patterns of cross-race face scanning. Therefore, experience in the community beyond the home appears to contribute to the development of differential scanning of own- versus other-race faces between 6 and 8 months of age.