Oxytocin Enhances the Neural Efficiency of Social Perception

Heart and shoal: Social cues and oxytocin receptors impact stress recovery in the zebrafish

In many species, social interactions decrease behavioral, hormonal, and neural responses to environmental stressors. While "social buffering" and its mechanisms have received considerable attention in mammals, we know less about the phenomenon in fish. The nonapeptide oxytocin regulates social behavior across vertebrates and plays an important role in social buffering in mammals. We investigated social buffering in the zebrafish by evaluating how the social environment and oxytocin receptors impact recovery from an acute stressor. Male and female fish were briefly exposed to alarm substance and recovered either in isolation or within view of a stimulus shoal. Alarm substance did not increase social approach, but social stimuli improved behavioral stress recovery. Oxytocin receptor antagonism decreased social approach during stress recovery and impaired stress recovery exclusively in individuals with access to visual social stimuli. Our findings contribute to the growing body of evidence that social stimuli buffer stress responses in fish and suggest that oxytocin receptors may play a role in socially-buffered stress recovery across taxa.

The effects of oxytocin administration on social and routinized behaviors in autism: A preregistered systematic review and meta-analysis

Oxytocin administration has demonstrated considerable promise for providing individualized support for autistic people. However, studies evaluating the effects of oxytocin administration on autistic characteristics have yielded inconsistent results. This systematic review and meta-analysis investigates the effect of oxytocin administration on social and routinized behaviors in autism using recently developed methods to accurately assess the potential impact of effect size dependency and publication bias. Our frequentist meta-analysis yielded a significant summary effect size estimate for the impact of oxytocin administration on social outcomes in autism (d = 0.22, p < 0.001). The summary effect size estimate for routinized behavior outcomes was not statistically significant (d = 0.14, p = 0.22), with a follow up test indicating that the effect size estimate was not either statistically equivalent (Z = -1.06, p = 0.2), assuming a smallest effect size of interest of 0.25. Frequentist and Bayesian assessments for publication bias, as well as results from Robust Bayesian meta-analysis of oxytocin effects on social outcomes in autism, indicated that summary effect sizes might be inflated due to publication bias. Future studies should aim to reduce bias by preregistering analysis plans and to increase precision with larger sample sizes.

Oxytocin modulates neural activity during early perceptual salience attribution

Leading hypotheses of oxytocin's (OT) role in human cognition posit that it enhances salience attribution. However, whether OT exerts its effects predominantly in social (vs non-social) contexts remains debatable, and the time-course of intranasal OT's effects' on salience attribution processing is still unknown. We used the social Salience Attribution Task modified (sSAT) in a double-blind, placebo-controlled intranasal OT (inOT) administration, between-subjects design, with 54 male participants, to test existing theories of OT's role in cognition. Namely, we aimed to test whether inOT would differently affect salience attribution processing of social stimuli (expressing fearfulness) and non-social stimuli (fruits) made relevant via monetary reinforcement, and its neural processing time-course. During electroencephalography (EEG) recording, participants made speeded responses to emotional social (fearful faces) and non-emotional non-social (fruits) stimuli - which were matched for task-relevant motivational salience through their (color-dependent) probability of monetary reinforcement. InOT affected early (rather than late, P3b and LPP) EEG components, increasing N170 amplitude (p = .041) and P2b latency (p .001; albeit not of P1), regardless of stimuli's (emotional) socialness or reinforcement probability. Fear-related socialness affected salience attribution processing EEG (p .05) across time (N170, P2b and P3b), being later modulated by reinforcement probability (LPP). Our data suggest that OT's effects on neural activity during early perception, may exist irrespective of fear-related social- or reward-contexts. This partially supports the tri-phasic model of OT (which posits OT enhances salience attribution in an early perception stage regardless of socialness), and not the social salience nor the general approach-withdrawal hypotheses of OT, for early salience processing event-related potentials.

Oxytocin differentially modulates the early neural responses to faces and non-social stimuli

Oxytocin (OT) alters social cognition partly through effects on the processing and appraisal of faces. It is debated whether the hormone also impacts the processing of other, non-social, visual stimuli. To this end, we conducted a randomized, counter-balanced, double-blind, placebo (PL)-controlled within-subjects' electro-encephalography (EEG) study with cismale participants (to control for gender dimorphic hormonal effects; n = 37). Participants received intranasal OT (24IU) and completed a one-back task viewing emotional (fearful/ happy) and neutral faces, and threat (snakes/spiders) and non-threat (mushrooms/flowers) non-social stimuli. OT differentially impacted event-related potentials (ERP)s to faces and non-social stimuli. For faces regardless of emotion, OT evoked greater occipital N1 and anterior P1 amplitudes at ∼155 ms than after PL, and lead to sustained differences over anterior, bilateral parietal and occipital sites from 205 ms onwards. For all non-social stimuli, OT evoked greater right parietal N1 amplitudes, and later only impacted threat stimuli over right parietal and occipital sites. None of these OT-induced modulations was related to individual anxiety levels. This pattern of results indicates that OT differentially modulates the processing of faces and non-social stimuli, and that the hormone's effect on visual processing and cognition does not occur as a function of non-clinical levels of anxiety.

Oxytocin enhances the triangular association among behavior, resting-state, and task-state functional connectivity

Considerable advances in the role of oxytocin (OT) effect on behavior and the brain network have been made, but the effect of OT on the association between inter-individual differences in functional connectivity (FC) and behavior is elusive. Here, by using a face-perception task and multiple connectome-based predictive models, we aimed to (1) determine whether OT could enhance the association among behavioral performance, resting-state FC (rsFC), and task-state FC (tsFC) and (2) if so, explore the role of OT in enhancing this triangular association. We found that in the OT group, the prediction performance of using rsFC or tsFC to predict task behavior was higher than that of the PL group. Additionally, the correlation coefficient between rsFC and tsFC was substantially higher in the OT group than in the PL group. The strength of these associations could be partly explained by OT altering the brain's FCs related to social cognition and face perception in both the resting and task states, mainly in brain regions such as the limbic system, prefrontal cortex, temporal poles, and temporoparietal junction. Taken together, these results provide novel evidence and a corresponding mechanism for how neuropeptides cause increased associations among inter-individual differences across different levels (e.g., behavior and large-scale brain networks in both resting and task-state), and may inspire future research on the role of neuropeptides in the cross levels association of both clinical and nonclinical use.

Sex differences in the rapid detection of neutral faces associated with emotional value

BACKGROUND

Rapid detection of faces with emotional meaning is essential for understanding the emotions of others, possibly promoting successful interpersonal relationships. Although few studies have examined sex differences in the ability to detect emotional faces, it remains unclear whether faces with emotional meaning capture the attention of females and males differently, because emotional faces have visual saliency that modulates visual attention. To overcome this issue, we tested the rapid detection of the neutral faces associated with and without learned emotional value, which are all regarded as free from visual saliency. We examined sex differences in the rapid detection of the neutral female and male faces associated with emotional value.

METHODS

First, young adult female and male participants completed an associative learning task in which neutral faces were associated with either monetary rewards, monetary punishments, or no monetary outcomes, such that the neutral faces acquired positive, negative, and no emotional value, respectively. Then, they engaged in a visual search task in which previously learned neutral faces were presented as discrepant faces among newly presented neutral distractor faces. During the visual search task, the participants were required to rapidly identify discrepant faces.

RESULTS

Female and male participants exhibited comparable learning abilities. The visual search results demonstrated that female participants achieved rapid detection of neutral faces associated with emotional value irrespective of the sex of the faces presented, whereas male participants showed this ability only for male faces.

CONCLUSIONS

Our results demonstrated that sex differences in the ability to rapidly detect neutral faces with emotional value were modulated by the sex of those faces. The results suggest greater sensitivity to faces with emotional significance in females, which might enrich interpersonal communication, regardless of sex.

The role of oxytocin in modulating self-other distinction in human brain: a pharmacological fMRI study

Self-other distinction is crucial for human interaction. Although with conflicting results, studies have found that oxytocin (OT) sharpens the self-other perceptual boundary. However, little is known about the effect of OT on self-other perception, especially its neural basis. Moreover, it is unclear whether OT influences self-other discrimination when the other is a child or an adult. This double-blind, placebo-controlled study investigated the effect of OT on self-face perception at the behavioral and neural levels. For the stimuli, we morphed participants' faces and child or adult strangers' faces, resulting in 4 conditions. After treatment with either OT or placebo, participants reported whether a stimulus resembled themselves while being scanned using functional magnetic resonance imaging (fMRI). Behavioral results showed that people judged adult-morphed faces better than child-morphed faces. Moreover, fMRI results showed that the OT group exhibited increased activity in visual areas and the inferior frontal gyrus for self-faces. This difference was more pronounced in the adult-face condition. In multivariate fMRI and region of interest analyses, better performance in the OT group indicated that OT increased self-other distinction, especially for adult faces and in the left hemisphere. Our study shows a significant effect of OT on self-referential processes, proving the potential effect of OT on a left hemisphere self-network.

The dual neural effects of oxytocin in autistic youth: results from a randomized trial

Recent discoveries have highlighted the effects of oxytocin (OT) on social behavior and perception among autistic individuals. However, a gap persists in the literature regarding the potential effects of OT and the neural temporal dynamics due to OT administration. We explored the effect of OT on autistic individuals using magnetoencephalography (MEG), focusing on M100, M170, and M250, social perception-related components that tend to show atypical patterns in autistic individuals. Twenty-five autistic adolescents participated in this randomized, double-blind MEG study. Autistic individuals arrived at the lab twice and received an acute dose of intranasal OT or placebo in each session. During the scans, participants were asked to identify pictures of social and non-social stimuli. Additionally, 23 typically developing (TD) adolescents performed the same task in the MEG as a benchmark that allowed us to better characterize neural regions of interest and behavioral results for this age group in this task. A source-model beamformer analysis revealed that OT enhanced neural activity for social stimuli in frontal regions during M170. Additionally, in each of the preselected time windows, OT increased activation in the left hemisphere, regardless of the content of the presented stimuli. We suggest that OT increased the processing of social stimuli through two separate mechanisms. First, OT increased neural activity in a nonspecific manner, allowing increased allocation of attention toward the stimuli. Second, OT enhanced M170 activity in frontal regions only in response to social stimuli. These results reveal the temporal dynamics of the effects of OT on the early stages of social and non-social perception in autistic adolescents.

Trial registration: This study was a part of a project registered as clinical trial October 27th, 2021. ClinicalTrials.gov Identifier: NCT05096676.

Frequency-Tagging EEG of Superimposed Social and Non-Social Visual Stimulation Streams Provides No Support for Social Salience Enhancement after Intranasal Oxytocin Administration

The social salience hypothesis proposes that the neuropeptide oxytocin (OT) can impact human social behavior by modulating the salience of social cues. Here, frequency-tagging EEG was used to quantify the neural responses to social versus non-social stimuli while administering a single dose of OT (24 IU) versus placebo treatment. Specifically, two streams of faces and houses were superimposed on one another, with each stream of stimuli tagged with a particular presentation rate (i.e., 6 and 7.5 Hz or vice versa). These distinctive frequency tags allowed unambiguously disentangling and objectively quantifying the respective neural responses elicited by the different streams of stimuli. This study involved a double-blind, placebo-controlled, cross-over trial with 31 healthy adult men. Based on four trials of 60 s, we detected robust frequency-tagged neural responses in each individual, with entrainment to faces being more pronounced in lateral occipito-temporal regions and entrainment to houses being focused in medial occipital regions. However, contrary to our expectation, a single dose of OT did not modulate these stimulus-driven neural responses, not in terms of enhanced social processing nor in terms of generally enhanced information salience. Bayesian analyses formally confirmed these null findings. Possibly, the baseline ceiling level performance of these neurotypical adult participants as well as the personal irrelevance of the applied stimulation streams might have hindered the observation of any OT effect.

Oxytocin but not naturally occurring variation in caregiver touch associates with infant social orienting

Caregiver touch is crucial for infants' healthy development, but its role in shaping infant cognition has been relatively understudied. In particular, despite strong premises to hypothesize its function in directing infant attention to social information, little empirical evidence exists on the topic. In this study, we investigated the associations between naturally occurring variation in caregiver touch and infant social attention in a group of 6- to 13-month-old infants (n = 71). Additionally, we measured infant salivary oxytocin as a possible mediator of the effects of touch on infant social attention. The hypothesized effects were investigated both short term, with respect to touch observed during parent-infant interactions in the lab, and long term, with respect to parent-reported patterns of everyday touching behaviors. We did not find evidence that caregiver touch predicts infant social attention or salivary oxytocin levels, short term or long term. However, we found that salivary oxytocin predicted infant preferential attention to faces relative to nonsocial objects, measured in an eye-tracking task. Our findings confirm the involvement of oxytocin in social orienting in infancy, but raise questions regarding the possible environmental factors influencing the infant oxytocin system.

Combinatorial approaches for treating neuropsychiatric social impairment

Social behaviour is an essential component of human life and deficits in social function are seen across multiple psychiatric conditions with high morbidity. However, there are currently no FDA-approved treatments for social dysfunction. Since social cognition and behaviour rely on multiple signalling processes acting in concert across various neural networks, treatments aimed at social function may inherently require a combinatorial approach. Here, we describe the social neurobiology of the oxytocin and endocannabinoid signalling systems as well as translational evidence for their use in treating symptoms in the social domain. We leverage this systems neurobiology to propose a network-based framework that involves pharmacology, psychotherapy, non-invasive brain stimulation and social skills training to combinatorially target trans-diagnostic social impairment. Lastly, we discuss the combined use of oxytocin and endocannabinoids within our proposed framework as an illustrative strategy to treat specific aspects of social function. Using this framework provides a roadmap for actionable treatment strategies for neuropsychiatric social impairment. This article is part of the theme issue 'Interplays between oxytocin and other neuromodulators in shaping complex social behaviours'.

Reading language of the eyes

The need for assessment of social skills in clinical and neurotypical populations has led to the widespread, and still increasing use of the 'Reading the Mind in the Eyes Test' (RMET) developed more than two decades ago by Simon Baron-Cohen and colleagues for evaluation of social cognition in autism. By analyzing most recent clinical and brain imaging data, we illuminate a set of factors decisive for using the RMET. Converging evidence indicates: (i) In neurotypical individuals, RMET scores are tightly correlated with other social skills (empathy, emotional intelligence, and body language reading); (ii) The RMET assesses recognition of facial affect, but also heavily relies on receptive language skills, semantic knowledge, and memory; (iii) RMET performance is underwritten by the large-scale ensembles of neural networks well-outside the social brain; (iv) The RMET is limited in its capacity to differentiate between neuropsychiatric conditions as well as between stages and severity of a single disorder, though it reliably distinguishes individuals with altered social cognition or elevated pathological traits from neurotypical persons; (v) Merely gender (as a social construct) rather than neurobiological sex influences performance on the RMET; (vi) RMET scores do not substantially decline in healthy aging, and they are higher with higher education level, cognitive abilities, literacy, and mental well-being; (vii) Accuracy on the RMET, and engagement of the social brain, are greater when emotions are expressed and recognized by individuals with similar cultural/ethnic background. Further research is required to better inform usage of the RMET as a tool for swift and reliable examination of social cognition. In light of comparable visual input from the RMET images and faces covered by masks due to COVID-19 regulations, the analysis is of value for keeping efficient social interaction during the current pandemic, in particular, in professional settings related to social communication.

Monitoring the effect of oxytocin on the neural sensitivity to emotional faces via frequency-tagging EEG: A double-blind, cross-over study

The neuropeptide oxytocin (OXT) is suggested to exert an important role in human social behaviors by modulating the salience of social cues. To date, however, there is mixed evidence whether a single dose of OXT can improve the behavioral and neural sensitivity for emotional face processing. To overcome difficulties encountered with classic event-related potential studies assessing stimulus-saliency, we applied frequency-tagging EEG to implicitly assess the effect of a single dose of OXT (24 IU) on the neural sensitivity for positive and negative facial emotions. Neutral faces with different identities were presented at 6 Hz, periodically interleaved with an expressive face (angry, fearful, and happy, in separate sequences) every fifth image (i.e., 1.2 Hz oddball frequency). These distinctive frequency tags for neutral and expressive stimuli allowed direct and objective quantification of the neural expression-categorization responses. The study involved a double-blind, placebo-controlled, cross-over trial with 31 healthy adult men. Contrary to our expectations, we did not find an effect of OXT on facial emotion processing, neither at the neural, nor at the behavioral level. A single dose of OXT did not evoke social enhancement in general, nor did it affect social approach-avoidance tendencies. Possibly ceiling performances in facial emotion processing might have hampered further improvement.

The role of oxytocin in regulating loneliness in old age

Loneliness is prevalent in old age and is associated with reduced positive social interactions. Building on studies showing that oxytocin (OT) levels rise during social interactions, we hypothesized that following participation in positive social interaction involving synchronized movements, OT levels would increase, while state loneliness levels would diminish. A total of 63 older adults (aged M = 78.93, SD = 9.99; Range = 65-101) participated in the study. Participants completed emotional and social loneliness scales and provided saliva samples pre- and post-participation in the "mirror game", which requires movement synchronization and is known to promote connectedness and closeness. Results indicate a reduced state of loneliness following the mirror game. Importantly, the change in OT levels predicted the change in social loneliness, defined as the absence of social interactions with people in the social network. On the other hand, emotional loneliness, marked by deficient emotional contact, only decreased among participants who experienced high levels of closeness with their partner in the mirror game. Findings suggest that context-dependent change in endogenous OT may serve as biomarker for the social effects of oxytocin on loneliness in old age and can help in the development of targeted interventions for treating loneliness in old age.

Reading Covered Faces

Covering faces with masks, due to mandatory pandemic safety regulations, we can no longer rely on the habitual daily-life information. This may be thought-provoking for healthy people, but particularly challenging for individuals with neuropsychiatric and neurodevelopmental conditions. Au fait research on reading covered faces reveals that: 1) wearing masks hampers facial affect recognition, though it leaves reliable inferring basic emotional expressions; 2) by buffering facial affect, masks lead to narrowing of emotional spectrum and dampen veridical evaluation of counterparts; 3) masks may affect perceived face attractiveness; 4) covered (either by masks or other veils) faces have a certain signal function introducing perceptual biases and prejudices; 5) reading covered faces is gender- and age-specific, being more challenging for males and more variable even in healthy aging; 6) the hampering effects of masks on social cognition occur over the globe; and 7) reading covered faces is likely to be supported by the large-scale assemblies of the neural circuits far beyond the social brain. Challenges and limitations of ongoing research and parallels to the Reading the Mind in the Eyes Test are assessed. Clarification of how masks affect face reading in the real world, where we deal with dynamic faces and have entrée to additional valuable social signals such as body language, as well as the specificity of neural networks underlying reading covered faces calls for further tailored research.

Sniffing submissiveness? Oxytocin administration in severe psychopathy

Psychopathy is a personality disorder associated with criminal behavior and violent recidivism, and therefore a burden to society. Social dominance is one of the characteristics of psychopathy that might contribute to these problems. Nevertheless, only few studies have objectively measured the relationship between socially dominant behavior and psychopathy. Therefore, the current study assessed performance of 21 forensic PCL-R confirmed psychopathic patients and 24 normal controls on a gaze aversion task, in which slower gaze aversion from masked angry faces compared to masked happy faces is a measure of reactive dominance. Moreover, the current study assessed the potential beneficial effects of the neuropeptide oxytocin. The results showed that psychopaths were not more dominant on the gaze aversion task compared to normal controls. However, the severity of psychopathy was positively correlated with reactive dominance. Crucially, a single nasal spray administration of oxytocin abolished the connection between psychopathy and reactive dominance. This implies that socially dominant psychopaths might benefit from oxytocin administration.

Social cognition in individuals born preterm

Faces hold a substantial value for effective social interactions and sharing. Covering faces with masks, due to COVID-19 regulations, may lead to difficulties in using social signals, in particular, in individuals with neurodevelopmental conditions. Daily-life social participation of individuals who were born preterm is of immense importance for their quality of life. Here we examined face tuning in individuals (aged 12.79 ± 1.89 years) who were born preterm and exhibited signs of periventricular leukomalacia (PVL), a dominant form of brain injury in preterm birth survivors. For assessing the face sensitivity in this population, we implemented a recently developed experimental tool, a set of Face-n-Food images bordering on the style of Giuseppe Arcimboldo. The key benefit of these images is that single components do not trigger face processing. Although a coarse face schema is thought to be hardwired in the brain, former preterms exhibit substantial shortages in the face tuning not only compared with typically developing controls but also with individuals with autistic spectrum disorders. The lack of correlations between the face sensitivity and other cognitive abilities indicates that these deficits are domain-specific. This underscores impact of preterm birth sequelae for social functioning at large. Comparison of the findings with data in individuals with other neurodevelopmental and neuropsychiatric conditions provides novel insights into the origins of deficient face processing.

The neuroscience of empathy and compassion in pro-social behavior

Research in the scientific literature increasingly demonstrates that empathy consists of multiple dimensions, and that defining empathy as a single encompassing term may be imprecise. Recent calls have been made for increasing empathy as means to increase pro-social behavior. However, contradictory evidence exists that empathy may reduce pro-social behavior. This debate has sparked confusion around what is empathy, along with the value of empathy in promoting pro-social behavior. This paper will examine recent advances in affective neuroscience to better understand the construct of empathy and its relationship to pro-social behavior. Individuals' responses to affective empathy, seeing the suffering of others can result in personal distress or empathic concern, which may then subsequently affect motivation for pro-social behavior. Current research in affective neuroscience suggests that combining compassion interventions in conjunction with both affective and cognitive empathy offers the most optimal likelihood that individuals will engage in pro-social behavior.

Face Tuning in Depression

The latest COVID-19 pandemic reveals that unexpected changes elevate depression bringing people apart, but also calling for social sharing. Yet the impact of depression on social cognition and functioning is not well understood. Assessment of social cognition is crucial not only for a better understanding of major depressive disorder (MDD), but also for screening, intervention, and remediation. Here by applying a novel experimental tool, a Face-n-Food task comprising a set of images bordering on the Giuseppe Arcimboldo style, we assessed the face tuning in patients with MDD and person-by-person matched controls. The key benefit of these images is that single components do not trigger face processing. Contrary to common beliefs, the outcome indicates that individuals with depression express intact face responsiveness. Yet, while in depression face sensitivity is tied with perceptual organization, in typical development, it is knotted with social cognition capabilities. Face tuning in depression, therefore, may rely upon altered behavioral strategies and underwriting brain mechanisms. To exclude a possible camouflaging effect of female social skills, we examined gender impact. Neither in depression nor in typical individuals had females excelled in face tuning. The outcome sheds light on the origins of the face sensitivity and alterations in social functioning in depression and mental well-being at large. Aberrant social functioning in depression is likely to be the result of deeply-rooted maladaptive strategies rather than of poor sensitivity to social signals. This has implications for mental well-being under the current pandemic conditions.

Oxytocin promotes prosocial behavior and related neural responses in infant macaques at-risk for compromised social development

Although positive effects of oxytocin (OT) on social functioning are well-demonstrated, little is known about the mechanisms through which OT may drive early social development, or its therapeutic efficacy in infancy. To address these critical issues, we investigated the effects of exogenous OT on neural (EEG) and behavioral responses during observation of live facial gestures in infant macaques with limited social exposure (i.e. nursery-reared). Three key findings were revealed. First, OT increased alpha suppression over posterior scalp regions during observation of facial gestures but not non-biological movement, suggesting that OT targets self-other matching and attentional cortical networks involved in social perception from very early infancy. Second, OT increased infant production of matching facial gestures and attention towards the most socially-relevant facial stimuli, both behaviors typically silenced by early social deprivation. Third, infants with higher cortisol levels appeared to benefit the most from OT, displaying greater improvements in prosocial behaviors after OT administration. Altogether, these findings suggest that OT promotes prosocial behaviors and associated neural responses likely impacted by early social adversity, and demonstrate the potential of OT administration to ameliorate social difficulties in the context of neurodevelopmental and early-emerging psychiatric disorders, at a developmental stage when brain plasticity is greatest.

The N170 event-related potential reflects delayed neural response to faces when visual attention is directed to the eyes in youths with ASD

Atypical neural response to faces is thought to contribute to social deficits in autism spectrum disorder (ASD). Compared to typically developing (TD) controls, individuals with ASD exhibit delayed brain responses to upright faces at a face-sensitive event-related potential (ERP), the N170. Given observed differences in patterns of visual attention to faces, it is not known whether slowed neural processing may simply reflect atypical looking to faces. The present study manipulated visual attention to facial features to examine whether directed attention to the eyes normalizes N170 latency in ASD. ERPs were recorded in 30 children and adolescents with ASD as well as 26 TD children and adolescents. Results replicated prior findings of shorter N170 latency to the eye region of the face in TD individuals. In contrast, those with ASD did not demonstrate modulation of N170 latency by point of regard to the face. Group differences in latency were most pronounced when attention was directed to the eyes. Results suggest that well-replicated findings of N170 delays in ASD do not simply reflect atypical patterns of visual engagement with experimental stimuli. These findings add to a body of evidence indicating that N170 delays are a promising marker of atypical neural response to social information in ASD. LAY SUMMARY: This study looks at how children's and adolescents' brains respond when looking at different parts of a face. Typically developing children and adolescents processed eyes faster than other parts of the face, whereas this pattern was not seen in ASD. Children and adolescents with ASD processed eyes more slowly than typically developing children. These findings suggest that observed inefficiencies in face processing in ASD are not simply reflective of failure to attend to the eyes.

Transport of oxytocin to the brain after peripheral administration by membrane-bound or soluble forms of receptors for advanced glycation end-products

Oxytocin (OT) is a neuropeptide hormone. Single and repetitive administration of OT increases social interaction and maternal behaviour in humans and mammals. Recently, it was found that the receptor for advanced glycation end-products (RAGE) is an OT-binding protein and plays a critical role in the uptake of OT to the brain after peripheral OT administration. Here, we address some unanswered questions on RAGE-dependent OT transport. First, we found that, after intranasal OT administration, the OT concentration increased in the extracellular space of the medial prefrontal cortex (mPFC) of wild-type male mice, as measured by push-pull microperfusion. No increase of OT in the mPFC was observed in RAGE knockout male mice. Second, in a reconstituted in vitro blood-brain barrier system, inclusion of the soluble form of RAGE (endogenous secretory RAGE [esRAGE]), an alternative splicing variant, in the luminal (blood) side had no effect on the transport of OT to the abluminal (brain) chamber. Third, OT concentrations in the cerebrospinal fluid after i.p. OT injection were slightly higher in male mice overexpressing esRAGE (esRAGE transgenic) compared to those in wild-type male mice, although this did not reach statistical significance. Although more extensive confirmation is necessary because of the small number of experiments in the present study, the reported data support the hypothesis that RAGE may be involved in the transport of OT to the mPFC from the circulation. These results suggest that the soluble form of RAGE in the plasma does not function as a decoy in vitro.

Face pareidolia in the brain: Impact of gender and orientation

Research on face sensitivity is of particular relevance during the rapidly evolving Covid-19 pandemic leading to social isolation, but also calling for intact interaction and sharing. Humans possess high sensitivity even to a coarse face scheme, seeing faces in non-face images where real faces do not exist. The advantage of non-face images is that single components do not trigger face processing. Here by implementing a novel set of Face-n-Thing images, we examined (i) how face tuning alters with changing display orientation, and (ii) whether it is affected by observers’ gender. Young females and males were presented with a set of Face-n-Thing images either with canonical upright orientation or inverted 180° in the image plane. Face impression was substantially impeded by display inversion. Furthermore, whereas with upright display orientation, no gender differences were found, with inversion, Face-n-Thing images elicited face impression in females significantly more often. The outcome sheds light on the origins of the face inversion effect in general. Moreover, the findings open a way for examination of face sensitivity and underwriting brain networks in neuropsychiatric conditions related to the current pandemic (such as depression and anxiety), most of which are gender/sex-specific.

Links Between the Neurobiology of Oxytocin and Human Musicality

The human species possesses two complementary, yet distinct, universal communication systems—language and music. Functional imaging studies have revealed that some core elements of these two systems are processed in closely related brain regions, but there are also clear differences in brain circuitry that likely underlie differences in functionality. Music affects many aspects of human behavior, especially in encouraging prosocial interactions and promoting trust and cooperation within groups of culturally compatible but not necessarily genetically related individuals. Music, presumably via its impact on the limbic system, is also rewarding and motivating, and music can facilitate aspects of learning and memory. In this review these special characteristics of music are considered in light of recent research on the neuroscience of the peptide oxytocin, a hormone that has both peripheral and central actions, that plays a role in many complex human behaviors, and whose expression has recently been reported to be affected by music-related activities. I will first briefly discuss what is currently known about the peptide’s physiological actions on neurons and its interactions with other neuromodulator systems, then summarize recent advances in our knowledge of the distribution of oxytocin and its receptor (OXTR) in the human brain. Next, the complex links between oxytocin and various social behaviors in humans are considered. First, how endogenous oxytocin levels relate to individual personality traits, and then how exogenous, intranasal application of oxytocin affects behaviors such as trust, empathy, reciprocity, group conformity, anxiety, and overall social decision making under different environmental conditions. It is argued that many of these characteristics of oxytocin biology closely mirror the diverse effects that music has on human cognition and emotion, providing a link to the important role music has played throughout human evolutionary history and helping to explain why music remains a special prosocial human asset. Finally, it is suggested that there is a potential synergy in combining oxytocin- and music-based strategies to improve general health and aid in the treatment of various neurological dysfunctions.

Tri-Phasic Model ofOxytocin (TRIO): A systematic conceptual review of oxytocin-related ERP research

BACKGROUND

The neuropeptide oxytocin (OT) has been shown to play a role in variety of cognitive and social processes and different hypotheses have been put forth to explain OT's effects on brain and behavior in humans. However, these previous explanatory accounts do not provide information about OT-related temporal modulation in the brain.

OBJECTIVES

This paper systematically reviewed intranasal OT administration studies employing event-related potentials (ERPs) and synthesized the existing evidence into a novel conceptual framework.

METHODS

Empirical studies, published until February 2020 and cited in major databases (EBSCOhost, PubMed, and Web of Science), were examined in accordance with PRISMA guidelines. To be included, studies had to: (i) employ intranasal administration of OT, as the chemical modulator; (ii) measure ERPs; (iii) be peer-reviewed journal articles; (iv) be written in English; and (v) examine human participants.

RESULTS

The search criteria yielded 17 empirical studies. The systematic review resulted in conceptualization of the Tri-Phasic Model ofOxytocin (TRIO), which builds on three processing stages: (i) perception, (ii) selection, and (iii) evaluation. While OT increases attention irrespective of stimuli characteristics in the perception stage, in the selection and evaluation stages, OT acts as a filter to guide attention selectively towards social over non-social stimuli and modulates prosociality/approach motivation associated with social stimuli.

CONCLUSIONS

TRIO offers an empirically-derived conceptual framework that can guide the study of OT-related modulation on attentional processes, starting very early in the processing stream. This novel account furthers theoretical understanding and informs empirical investigation into OT modulation on the brain.

Acute oxytocin effects in inferring others' beliefs and social emotions in people at clinical high risk for psychosis

Social deficits are key hallmarks of the Clinical High Risk for Psychosis (CHR-P) state and of established psychotic disorders, and contribute to impaired social functioning, indicating a potential target for interventions. However, current treatments do not significantly ameliorate social impairments in CHR-P individuals. Given its critical role in social behaviour and cognition, the oxytocinergic (OT) system is a promising target for novel interventions in CHR-P subjects. In a double-blind, placebo-controlled, crossover design, 30 CHR-P males were studied using functional magnetic resonance imaging (fMRI) on two occasions, once after 40IU self-administered intranasal OT and once after placebo. A modified version of the Sally-Anne task was used to assess brain activation during inferring others' beliefs and social emotions. The Reading the Mind in the Eyes Test was acquired prior to the first scan to test whether OT effects were moderated by baseline social-emotional abilities. OT did not modulate behavioural performances but reduced activation in the bilateral inferior frontal gyrus compared with placebo while inferring others' social emotions. Furthermore, the relationship between brain activation and task performance after OT administration was moderated by baseline social-emotional abilities. While task accuracy during inferring others' social emotion increased with decreasing activation in the left inferior frontal gyrus in CHR-P individuals with low social-emotional abilities, there was no such relationship in CHR-P individuals with high social-emotional abilities. Our findings may suggest that acute OT administration enhances neural efficiency in the inferior frontal gyrus during inferring others' social emotions in those CHR-P subjects with low baseline social-emotional abilities.

Perceptual mechanisms of social affiliation in zebrafish

Social living animals need to recognize the presence of conspecifics in the environment in order to engage in adaptive social interactions. Social cues can be detected through different sensory modalities, including vision. Two main visual features can convey information about the presence of conspecifics: body form and biological motion (BM). Given the role that oxytocin plays in social behavior regulation across vertebrates, particularly in the salience and reward values of social stimuli, we hypothesized that it may also be involved in the modulation of perceptual mechanisms for conspecific detection. Here, using videoplaybacks, we assessed the role of conspecific form and BM in zebrafish social affiliation, and how oxytocin regulates the perception of these cues. We demonstrated that while each visual cue is important for social attraction, BM promotes a higher fish engagement than the static conspecific form alone. Moreover, using a mutant line for one of the two oxytocin receptors, we show that oxytocin signaling is involved in the regulation of BM detection but not conspecific form recognition. In summary, our results indicate that, apart from oxytocin role in the regulation of social behaviors through its effect on higher-order cognitive mechanisms, it may regulate social behavior by modulating very basic perceptual mechanisms underlying the detection of socially-relevant cues.