Neural activation to babyfaced men matches activation to babies

Age differences in Neural Activation to Face Trustworthiness: Voxel Pattern and Activation Level Assessments

Judgment of trustworthiness is an important social ability. Many studies show neural activation differences to variations in face trustworthiness in brain reward regions. A previously published analysis of the present fMRI data showed that older adults' (OA) reward region activation responded significantly to trustworthiness in a set of older and younger faces, whereas younger adults' (YA) activation did not-a finding inconsistent with studies that used only younger faces. We hypothesized that voxel pattern analyses would be more sensitive to YA neural responses to trustworthiness in our set of faces, replicating YA neural discrimination in prior literature. Based on evidence for OA neural dedifferentiation, we also hypothesized that voxel pattern analyses would more accurately classify YA than OA neural responses to face trustworthiness. We reanalyzed the data with two pattern classification models and evaluated the models' performance with permutation testing. Voxel patterns discriminated face trustworthiness levels in both YA and OA reward regions, while allowing better classification of face trustworthiness for YA than OA, the reverse of previous results for neural activation levels. The moderation of age differences by analytic method shines a light on the possibility that voxel patterns uniquely index neural representations of the stimulus information content, consistent with findings of impaired representation with age.

The Caring Continuum: Evolved Hormonal and Proximal Mechanisms Explain Prosocial and Antisocial Extremes

Implicit in the long-standing disagreements about whether humans’ fundamental nature is predominantly caring or callous is an assumption of uniformity. This article reviews evidence that instead supports inherent variation in caring motivation and behavior. The continuum between prosocial and antisocial extremes reflects variation in the structure and function of neurohormonal systems originally adapted to motivate parental care and since repurposed to support generalized forms of care. Extreme social behaviors such as extraordinary acts of altruism and aggression can often be best understood as reflecting variation in the neural systems that support care. A review of comparative, developmental, and neurobiological research finds consistent evidence that variations in caring motivations and behavior reflect individual differences in sensitivity to cues that signal vulnerability and distress and in the tendency to generalize care outward from socially close to distant others. The often complex relationships between caring motivation and various forms of altruism and aggression are discussed.

Glued to Which Face? Attentional Priority Effect of Female Babyface and Male Mature Face

A more babyfaced individual is perceived as more child-like and this impression from babyface, as known as babyface effect, has an impact on social life among various age groups. In this study, the influence of babyfaces on visual selective attention was tested by cognitive task, demonstrating that the female babyface and male mature face would draw participants’ attention so that they take their eyes off more slowly. In Experiment 1, a detection task was applied to test the influence of babyfaces on visual selective attention. In this experiment, a babyface and a mature face with the same gender were presented simultaneously with a letter on one of them. The reaction time was shorter when the target letter was overlaid with a female babyface or male mature face, suggesting an attention capture effect. To explore how this competition influenced by attentional resources, we conducted Experiment 2 with a spatial cueing paradigm and controlled the attentional resources by cueing validity and inter-stimulus interval. In this task, the female babyface and male mature face prolonged responses to the spatially separated targets under the condition of an invalid and long interval pre-cue. This observation replicated the result of Experiment 1. This indicates that the female babyface and male mature face glued visual selective attention once attentional resources were directed to them. To further investigate the subliminal influence from a babyface, we used continuous flash suppression paradigm in Experiment 3. The results, again, showed the advantage of the female babyfaces and male mature faces: they broke the suppression faster than other faces. Our results provide primary evidence that the female babyfaces and male mature faces can reliably glue the visual selective attention, both supra- and sub-liminally.

Patterns of Eye Movements When Observers Judge Female Facial Attractiveness

The purpose of the present study is to explore the fixed model for the explicit judgments of attractiveness and infer which features are important to judge the facial attractiveness. Behavioral studies on the perceptual cues for female facial attractiveness implied three potentially important features: averageness, symmetry, and sexual dimorphy. However, these studies did not explained which regions of facial images influence the judgments of attractiveness. Therefore, the present research recorded the eye movements of 24 male participants and 19 female participants as they rated a series of 30 photographs of female facial attractiveness. Results demonstrated the following: (1) Fixation is longer and more frequent on the noses of female faces than on their eyes and mouths (no difference exists between the eyes and the mouth); (2) The average pupil diameter at the nose region is bigger than that at the eyes and mouth (no difference exists between the eyes and the mouth); (3) the number of fixations of male participants was significantly more than female participants. (4) Observers first fixate on the eyes and mouth (no difference exists between the eyes and the mouth) before fixating on the nose area. In general, participants attend predominantly to the nose to form attractiveness judgments. The results of this study add a new dimension to the existing literature on judgment of facial attractiveness. The major contribution of the present study is the finding that the area of the nose is vital in the judgment of facial attractiveness. This finding establish a contribution of partial processing on female facial attractiveness judgments during eye-tracking.

Seeing overweight adults as babies: Physical cues and implications for stigmatization

Human babies not only are reliable triggers of tender feelings and protective tendencies, they also happen to be exceptionally fat compared to the newborns of most other species. These two facts are used to formulate a hypothesis predicting that overweight males, due to their great physical resemblance to babies, not only are perceived as cute, but also are associated with negatively evaluated traits (e.g., immaturity, lack of willpower) that are saliently inconsistent with traits required for adults. In this study, a great many physical features of adult males varying widely in weight were measured and correlated with subjective judgements. Providing preliminary support for the hypothesis, it was found that the features that were correlated with objective and perceived fatness (e.g., circularity of body parts, relatively large head, short and thick neck) also correlated with perceived babyishness. Perceived fatness and babyishness had curvilinear influences on the positive and prosocial appraisal of cuteness, but were primarily negatively related to perceived willpower and beauty. Results are used to formulate an alternative evolutionary perspective on social responses to overweight and obese individuals, emphasizing the uniquely human adaptive value of fatness and the misfiring of the underlying response mechanism under modern conditions of living.

Neural correlates of babyish adult face processing in men

The morphological characteristics of an infant's face are collectively referred to as baby schema or babyishness. It has been well established that infant traits are implicitly projected, or overgeneralized, to adults with babyish facial features. However, few studies to date have investigated the neural underpinnings of such overgeneralization. In the present study, we addressed this issue by comparing neural activations elicited by baby-faced and mature-faced adult faces in men using fMRI. We found increased activations in clusters surrounding the bilateral insula, bilateral anterior cingulate cortex, and right inferior frontal gyrus, which have been previously linked to the processing of facial attractiveness and infant-related information. We also discovered increased activation in the left medial prefrontal cortex, which might be related to emotional or empathic responses directed towards baby-faced adults. The activated region also included the left premotor cortex, which presumably reflects an embodied response or approach motivation directed toward infant-related information. Furthermore, the activation level of the left caudate correlated with the salivary concentration of oxytocin. Taken together, these findings indicate that passive viewing of babyish adult faces induces increased responses in neural regions linked to facial attractiveness and infant-related information processing, and that these responses are partially influenced by oxytocinergic factors.

Neural systems and hormones mediating attraction to infant and child faces

We find infant faces highly attractive as a result of specific features which Konrad Lorenz termed “Kindchenschema” or “baby schema,” and this is considered to be an important adaptive trait for promoting protective and caregiving behaviors in adults, thereby increasing the chances of infant survival. This review first examines the behavioral support for this effect and physical and behavioral factors which can influence it. It then provides details of the increasing number of neuroimaging and electrophysiological studies investigating the neural circuitry underlying this baby schema effect in parents and non-parents of both sexes. Next it considers potential hormonal contributions to the baby schema effect in both sexes and the neural effects associated with reduced responses to infant cues in post-partum depression, anxiety and drug taking. Overall the findings reviewed reveal a very extensive neural circuitry involved in our perception of cuteness in infant faces, with enhanced activation compared to adult faces being found in brain regions involved in face perception, attention, emotion, empathy, memory, reward and attachment, theory of mind and also control of motor responses. Both mothers and fathers also show evidence for enhanced responses in these same neural systems when viewing their own as opposed to another child. Furthermore, responses to infant cues in many of these neural systems are reduced in mothers with post-partum depression or anxiety or have taken addictive drugs throughout pregnancy. In general reproductively active women tend to rate infant faces as cuter than men, which may reflect both heightened attention to relevant cues and a stronger activation in their brain reward circuitry. Perception of infant cuteness may also be influenced by reproductive hormones with the hypothalamic neuropeptide oxytocin being most strongly associated to date with increased attention and attraction to infant cues in both sexes.

The Face–Time Continuum

Aging influences how a person is perceived on multiple dimensions (e.g., physical power). Here we examined how facial structure informs these evolving social perceptions. Recent work examining young adults’ faces has revealed the impact of the facial width-to-height ratio (fWHR) on perceived traits, such that individuals with taller, thinner faces are perceived to be less aggressive, less physically powerful, and friendlier. These perceptions are similar to those stereotypically associated with older adults. Examining whether fWHR might contribute to these changing perceptions over the life span, we found that age provides a shifting context through which fWHR differentially impacts aging-related social perceptions (Study 1). In addition, archival analyses (Study 2) established that fWHR decreases across age, and a subsequent study found that fWHR mediated the relationship between target age and multiple aging-related perceptions (Study 3). The findings provide evidence that fWHR decreases across age and influences stereotypical perceptions that change with age.

Understanding the human parental brain: a critical role of the orbitofrontal cortex

The bond between a parent and an infant often appears to form effortlessly and intuitively, and this relationship is fundamental to infant survival and development. Parenting is considered to depend on specific brain networks that are largely conserved across species and in place even before parenthood. Efforts to understand the neural basis of parenting in humans have focused on the overlapping networks implicated in reward and social cognition, within which the orbitofrontal cortex (OFC) is considered to be a crucial hub. This review examines emerging evidence that the OFC may be engaged in several phases of parent-infant interactions, from early, privileged orienting to infant cues, to ongoing monitoring of interactions and subsequent learning. Specifically, we review evidence suggesting that the OFC rapidly responds to a range of infant communicative cues, such as faces and voices, supporting their efficient processing. Crucially, this early orienting response may be fundamental in supporting adults to respond rapidly and appropriately to infant needs. We suggest a number of avenues for future research, including investigating neural activity in disrupted parenting, exploring multimodal cues, and consideration of neuroendocrine involvement in responsivity to infant cues. An increased understanding of the brain basis of caregiving will provide insight into our greatest challenge: parenting our young.

The influence of oxytocin administration on responses to infant faces and potential moderation by OXTR genotype

RATIONALE

Oxytocin is a neuropeptide that is associated with increases in social affiliative behaviors, particularly toward infants. However, no previous study has investigated healthy adults' responses to infant faces following oxytocin administration. In addition, given that preliminary evidence suggests that a single-nucleotide polymorphism of the oxytocin receptor (OXTR) gene, rs53576, may influence behaviors associated with parental sensitivity, we assessed whether such responses vary according to OXTR rs53576 genotype.

OBJECTIVES

The present study assessed the effects of intranasally administered oxytocin and OXTR genotype on human adults' preferences for infant faces.

METHODS

A double-blind, between-groups design was used, with 57 genotyped volunteers randomly assigned to receive intranasally administered oxytocin or placebo. Fifty minutes following the administration of oxytocin or placebo, participants viewed infants' and adults' faces showing neutral expressions and assessed how appealing they found each face.

RESULTS

Infants' faces were more strongly preferred following oxytocin inhalation relative to placebo. When participants were separated according to genotype, this effect was only observed for participants homozygous for the rs53576G allele. Parallel effects were not seen for adults' faces.

CONCLUSIONS

The present results are consistent with the hypothesis that acute oxytocin administration increases sensitivity to reward-relevant features of infants and/or reduces sensitivity to their aversive properties. The results are also consistent with suggestions of more efficient oxytocinergic function in rs53576G homozygotes.

Neural activation in the "reward circuit" shows a nonlinear response to facial attractiveness

Positive behavioral responses to attractive faces have led neuroscientists to investigate underlying neural mechanisms in a "reward circuit" that includes brain regions innervated by dopamine pathways. Using male faces ranging from attractive to extremely unattractive, disfigured ones, this study is the first to demonstrate heightened responses to both rewarding and aversive faces in numerous areas of this putative reward circuit. Parametric analyses employing orthogonal linear and nonlinear regressors revealed positive nonlinear effects in anterior cingulate cortex, lateral orbital frontal cortex (LOFC), striatum (nucleus accumbens, caudate, putamen), and ventral tegmental area, in addition to replicating previously documented linear effects in medial orbital frontal cortex (MOFC) and LOFC and nonlinear effects in amygdala and MOFC. The widespread nonlinear responses are consistent with single cell recordings in animals showing responses to both rewarding and aversive stimuli, and with some human fMRI investigations of non-face stimuli. They indicate that the reward circuit does not process face valence with any simple dissociation of function across structures. Perceiver gender modulated some responses to our male faces: Women showed stronger linear effects, and men showed stronger nonlinear effects, which may have functional implications. Our discovery of nonlinear responses to attractiveness throughout the reward circuit echoes the history of amygdala research: Early work indicated a linear response to threatening stimuli, including faces; later work also revealed a nonlinear response with heightened activation to affectively salient stimuli regardless of valence. The challenge remains to determine how such dual coding influences feelings, such as pleasure and pain, and guides goal-related behavioral responses, such as approach and avoidance.

Effective connectivity between amygdala and orbitofrontal cortex differentiates the perception of facial expressions

Emotion research is guided both by the view that emotions are points in a dimensional space, such as valence or approach-withdrawal, and by the view that emotions are discrete categories. We determined whether effective connectivity of amygdala with medial orbitofrontal cortex (MOFC) and lateral orbitofrontal cortex (LOFC) differentiates the perception of emotion faces in a manner consistent with the dimensional and/or categorical view. Greater effective connectivity from left MOFC to amygdala differentiated positive and neutral expressions from negatively valenced angry, disgust, and fear expressions. Greater effective connectivity from right LOFC to amygdala differentiated emotion expressions conducive to perceiver approach (happy, neutral, and fear) from angry expressions that elicit perceiver withdrawal. Finally, consistent with the categorical view, there were unique patterns of connectivity in response to fear, anger, and disgust, although not in response to happy expressions, which did not differ from neutral ones.

Social Psychological Face Perception: Why Appearance Matters

We form first impressions from faces despite warnings not to do so. Moreover, there is considerable agreement in our impressions, which carry significant social outcomes. Appearance matters because some facial qualities are so useful in guiding adaptive behavior that even a trace of those qualities can create an impression. Specifically, the qualities revealed by facial cues that characterize low fitness, babies, emotion, and identity are overgeneralized to people whose facial appearance resembles the unfit (anomalous face overgeneralization), babies (babyface overgeneralization), a particular emotion (emotion face overgeneralization), or a particular identity (familiar face overgeneralization). We review studies that support the overgeneralization hypotheses and recommend research that incorporates additional tenets of the ecological theory from which these hypotheses are derived: the contribution of dynamic and multi-modal stimulus information to face perception; bidirectional relationships between behavior and face perception; perceptual learning mechanisms and social goals that sensitize perceivers to particular information in faces.