Let me in: The neural correlates of inclusion motivation in loneliness.

BACKGROUND: While it is well-established that humans possess an innate need for social belonging, the neural mechanisms underlying motivation for connection are still largely unknown. We propose that inclusion motivation - measured through the effort that individuals are willing to invest to be included in social interactions - may serve as one of the basic building blocks of social behavior and may change in lonely individuals. METHODS: Following the screening of 303 participants, we scanned 30 low- and 28 high-loneliness individuals with functional magnetic resonance imaging while they performed the Active Inclusion Task (AIT). The AIT assesses the participants' levels of effort invested in influencing their inclusion during classic Cyberball conditions of fair play and exclusion. RESULTS: High- compared to low-loneliness individuals showed higher urgency for inclusion, specifically during fair play, which correlated with higher activity in the right thalamus. Furthermore, in high-loneliness individuals, we found increased functional connectivity between the thalamus and the temporoparietal junction, putamen, and insula. LIMITATIONS: Participants interacted with computerized avatars, reducing ecological validity. Additionally, although increasing inclusion in the task required action, the physical demand was not high. Additional limitations are discussed. CONCLUSIONS: Inclusion motivation in loneliness is heightened during fair but not exclusionary interactions, and is linked to activity in brain regions implicated in appetitive behavior and social cognition. The findings indicate that lonely individuals may view threat in inclusionary interactions, prompting them to take action to regain connection. This suggests that inclusion motivation may help explain social difficulties in loneliness.

Fluctuations in loneliness due to changes in frequency of social interactions among older adults: a weekly based diary study.

OBJECTIVES: Loneliness functionally varies and is determined by the degree of interaction with others. We examined weekly fluctuations in reported loneliness as a function of frequency of social interactions in old age. We hypothesized that emotional and social components of loneliness would be related to different types of social relationships. DESIGN: Participants reported their feeling of loneliness and their social interaction quantity (frequency of meetings) via a weekly based diary, over 6 weeks. SETTING: Diary study. PARTICIPANTS: The study included 55 older adults with different dwelling arrangements (M = 73.4, SD = 6.97). MEASUREMENTS: Measures of Loneliness (the De Jong-Gierveld Loneliness Scale), Social Interaction and Contact, and sociodemographic parameters were used. RESULTS: Social and emotional loneliness fluctuated over the course of the 6-week study. Frequency of meeting friends was related to emotional loneliness and total feelings of loneliness. Frequency of meeting close/trusted figures was related to emotional loneliness which appeared the following week. Other variables were not associated with either changes in loneliness or its dimensions. CONCLUSIONS: Loneliness in old age is changeable. The emotional component of loneliness seems to be dominant in determining overall feelings of loneliness and is more sensitive to externally chosen social interaction.

Inter-group conflict affects inter-brain synchrony during synchronized movements.

Interpersonal synchrony refers to alignment in time of interacting individuals. Recent neuroimaging findings indicate that the inferior frontal gyrus (IFG) - a core region of the observation-execution system - is not only activated during tasks that involve synchrony, but also coupled between interaction partners, suggesting a key role for the IFG in mediating interpersonal synchrony. In this study we investigated whether inter-brain synchrony (IBS) is modulated by inter-group relationships. We examined this question in the context of the Israeli-Palestinian conflict - one of the world's most prolonged and intractable conflicts. Using functional Near Infra-Red Spectroscopy (fNIRS) hyperscanning, we measured IBS among ingroup vs. inter-group dyads (same-nationality dyads and Jewish-Palestinian dyads, respectively) while they performed a task entailing 2D movement synchrony. The results point to an increase in behavioral synchrony and greater enjoyment in the ingroup dyads, compared to the inter-group dyads. Critically, IBS in the left IFG significantly increased throughout task and it was higher among ingroup compared to inter-group dyads. Our findings highlight the effect of group membership on IBS plasticity.

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.

Getting in touch: A neural model of comforting touch.

Comforting touch involves contact distress-alleviating behaviors of an observer towards the suffering of a target. A growing number of studies have investigated the effects of touch on pain attenuation, focusing on the (toucher), the target (comforted) or both. Here we synthesize findings of brain mechanisms underlying comforting touch in the target and toucher to propose an integrative brain model for understanding how touch attenuates distress. Building on evidence from the pain and distress literatures, our model applies interchangeably to pain and distress regulation. We describe comforting touch as a feedback-loop that begins with distress experienced by the target, triggering an empathic response in the toucher which in turn reduces distress in the target. This cycle is mediated by interactions between the neural circuits associated with touch perception, shared distress, emotion regulation and reward as well as brain-to-brain coupling in the observation-execution system. We conclude that formulating a model of comforting touch offers a mechanistic framework for understanding the effects of touch as well as other social interactions involving social support.

Herding in human groups is related to high autistic traits.

Herding is ubiquitous throughout all social life forms, providing beneficial outcomes. Here, we examine whether herding emerges spontaneously in human groups and whether it adheres to the core principles of herding observed in the animal kingdom. Using a computerized paradigm involving the movements of circles, we tested the emergence of spontaneous and intentional herding of 136 participants assigned into groups of four participants. Herding was assessed by measuring directional synchrony in the movements of the circles, level of cohesion, and separation between circles. We found that human groups tend to spontaneously herd, particularly in terms of directional synchrony, supporting the notion of a human herding instinct. We further asked whether individuals with high traits of Autism Spectrum Disorder (ASD) exhibit differences in their herding tendencies. Results indicated that individuals with high ASD traits showed greater social separation from the group, compared to individuals with low ASD traits. Moreover, we found diminished spontaneous synchrony, but intact instructed synchrony in the high vs. the low ASD traits group. We contend that humans spontaneously herd with their group and suggest that the spontaneous tendency to synchronize with others is diminished in individuals with high ASD traits, though it is recovered when synchronization is intentional.

The sociality of social inhibition of return.

Cognitive processes are traditionally studied in individual settings, while the possible effect of the social context is ignored. The present study focuses on the social inhibition of return effect (SIOR; Welsh et al., 2005). According to it, observation of another person's action at a specific location initiates an inhibitory process in the observer at that location. The aim of the present study was to investigate which processes are influenced by the social context (e.g. action representation, attention, etc.) and whether this effect is elicited only in a social context. In a series of four experiments we examined the SIOR effect by developing a dyadic computerized task in which each participant, in turn, responded to a peripherally presented target in two successive trials. The first trial was performed after the other participant had responded and was designed to examine SIOR. The second trial was aimed at studying self-induced IOR. The first two experiments replicated and extended previous findings by demonstrating that information regarding the counterpart's response location was sufficient to produce SIOR. In the third experiment the participants performed the same task but without a counterpart so that SIOR was eliminated. The fourth experiment demonstrated that believing there is a co-actor is enough to elicit the SIOR effect. These findings suggest that knowing that a location was acted upon before by another person (by observation or by prior knowledge) is the minimal condition for the SIOR effect to be evoked.

Androstadienone, a putative chemosignal of dominance, increases gaze avoidance among men with high social anxiety.

Socially anxious individuals show increased sensitivity toward social threat signals, including cues of dominance. This sensitivity may account for the hypervigilance and gaze avoidance commonly reported in individuals with social anxiety. This study examines visual scanning behavior in response to androstadienone (androsta-4,16,-dien-3-one), a putative chemosignal of dominance. We tested whether exposure to androstadienone would increase hypervigilance and gaze avoidance among individuals with high social anxiety. In a double-blind, placebo-controlled, within-subject design, 26 participants with high social anxiety and 26 with low social anxiety were exposed to androstadienone and a control solution on two separate days. On each day, an eye-tracker recorded their spontaneous scanning behavior while they viewed facial images of men depicting dominant and neutral poses. The results indicate that among participants with high social anxiety, androstadienone increased gaze avoidance by reducing the percentage of fixations made to the eye-region and the total amount of time spent gazing at the eye-region of the faces. Participants with low social anxiety did not show this effect. These findings indicate that androstadienone serves as a threatening chemosignal of dominance, further supporting the link between hypersensitivity toward social threat cues and the perpetuation of social anxiety.

Empathy during consoling touch is modulated by mu-rhythm: An EEG study.

The aim of the present study was to examine the mechanisms of empathy for pain that contribute to consoling touch, a distress-alleviating contact behavior carried out by an observer in response to the suffering of a target. We tested romantic couples in a paradigm that involves consoling touch and examined the attenuation of the mu/alpha rhythm (8-13Hz) in the consoling partner. During the task, the toucher either held the consoled partner's right hand (human touch) or held onto the armrest of the chair (non-human touch), while the consoled partner experienced inflicted pain (pain condition) or did not experience any pain (no-pain condition). In accordance with our hypotheses, the results revealed an interaction between touch and pain at in mu/alpha rhythms in all central sites (C3, C4, Cz). Specifically, we found that the toucher's mu suppression was higher in the consoling touch condition, i.e., while touching the partner who is in pain, compared to the three control conditions. Additionally, we found that in the consoling touch condition, mu suppression at electrode C4 of the toucher correlated with a measure of situational empathy. Our findings suggest that electrophysiological and behavioral measures that have been associated with empathy for pain are modulated during consoling touch.

Intranasal administration of oxytocin increases human aggressive behavior.

Considering its role in prosocial behaviors, oxytocin (OT) has been suggested to diminish levels of aggression. Nevertheless, recent findings indicate that oxytocin may have a broader influence on increasing the salience of social stimuli and may therefore, under certain circumstances, increase antisocial behaviors such as aggression. This controversy led to the following speculations: If indeed oxytocin promotes primarily prosocial behavior, administration of OT is expected to diminish levels of aggression. However, if oxytocin mainly acts to increase the salience of social stimuli, it is expected to elevate levels of aggression following provocation. In order to test this assumption we used the Social Orientation Paradigm (SOP), a monetary game played against a fictitious partner that allows measuring three types of responses in the context of provocation: an aggressive response - reducing a point from the fictitious partner, an individualistic response - adding a point to oneself, and a collaborative response - adding half a point to the partner and half a point to oneself. In the current double-blind, placebo-controlled, within-subject study design, 45 participants completed the SOP task following the administration of oxytocin or placebo. The results indicated that among subjects naïve to the procedure oxytocin increased aggressive responses in comparison with placebo. These results support the saliency hypothesis of oxytocin and suggest that oxytocin plays a complex role in the modulation of human behavior.

Enhancing verbal creativity: modulating creativity by altering the balance between right and left inferior frontal gyrus with tDCS.

Creativity is the production of novel ideas that have value. Previous research indicated that while regions in the right hemisphere are implicated in the production of new ideas, damage to the left inferior frontal gyrus (IFG) is associated with increased creativity, indicating that the left IFG damage may have a "releasing" effect on creativity. To examine this, in the present study we used transcranial direct current stimulation (tDCS) to modulate activity of the right and the left IFG. In the first experiment we show that whereas anodal tDCS over the right IFG coupled with cathodal tDCS over the left IFG increases creativity as measured by a verbal divergent thinking task, the reverse stimulation does not affect creative production. To further confirm that only altering the balance between the two hemispheres is crucial in modulating creativity, in the second experiment we show that stimulation targeting separately the left IFG (cathodal stimulation) or the right IFG (anodal stimulation) did not result in changes in creativity as measured by verbal divergent thinking. These findings support the balance hypothesis, according to which verbal creativity requires a balance of activation between the right and the left frontal lobes, and more specifically, between the right and the left IFG.

The role of oxytocin in empathy to the pain of conflictual out-group members among patients with schizophrenia.

BACKGROUND: Oxytocin (OT) is associated with our ability to empathize and has been shown to play a major role in mediating social behaviors within the context of intergroup dynamics. Schizophrenia is associated with impaired empathy, and with a dysfunctional oxytocinergic system. The effect of OT on the empathic responses of patients with schizophrenia within the context of intergroup relationships has not been studied. The present study examined the effect of OT on the patients' empathic responses to pain experienced by in-group, conflictual out-group and neutral out-group members. METHOD: In a double-blind, placebo-controlled, within-subject cross-over design, the responses on the Pain Evaluation Task of 28 male patients with schizophrenia were compared to 27 healthy male controls. All participants received a single intranasal dose of 24 IU OT or placebo, 1 week apart. RESULTS: OT induced an empathy bias in the healthy controls towards the conflictual out-group members. Although this effect was absent in the patient group, OT seems to heighten an empathic bias in the patient group towards the in-group members when rating non-painful stimuli. CONCLUSIONS: The study demonstrates that the administration of OT can result in empathic bias towards adversary out-group members in healthy controls but not in patients with schizophrenia. However, the OT-induced bias in both the patients (in the no-pain condition towards the in-group members) and the healthy controls (in the no-pain and pain conditions towards the adversary out-group) suggests that OT enhances the distinction between conflictual in-group and out-group members.

The gender you are and the gender you like: sexual preference and empathic neural responses.

BACKGROUND: Empathy relates to the ability to share the emotions and understand the intentions and emotions of the other. Although it has been suggested that women have superior empathic abilities as compared to men, it is unknown whether it is the gender or the sexual preference of the individual that affects empathy. Given that sexual attraction has been reported to affect social behavior, the present study explored the possibility that sexual orientation affects behavioral measures of empathy as well as empathy related activations. METHODS: Fifty two heterosexual and homosexual women and men were scanned while performing an emotional judgment task involving emotional understanding of a protagonist. RESULTS: The behavioral and neuroimaging results indicate that empathy is related to the gender as well as the sexual preference of the participant. Individuals sexually attracted to men (heterosexual women and homosexual men) showed greater empathy than subjects attracted to women (heterosexual men and homosexual women). Furthermore, brain imaging data reveal that regions within the temporo-parietal junction (TPJ), showed sensitivity to the sexual orientation of the individual, such that it was activated more in subjects attracted to men than in subjects attracted to women while evaluating the emotional state of the other. Moreover, the activation in the TPJ was found to be correlated with the degree to which subjects were empathizing. CONCLUSIONS: These results suggest that individual differences in empathy are related to the gender as well as the sexual orientation of the subject.

Improving social perception in schizophrenia: the role of oxytocin.

Previous research has shown that patients with schizophrenia are impaired in a wide range of social cognitive abilities, including emotion recognition, empathy for others, and mental perspective-taking. Recent studies suggest that a dysfunction of the oxytocinergic system contributes to the social impairment in schizophrenia. Accordingly, the present study sought to examine whether patients with schizophrenia would improve in a social perception task after taking a single dose of oxytocin, as compared to a placebo. Thirty-five patients diagnosed with schizophrenia were compared with 46 psychologically healthy matched controls on their recognition of kinship and intimacy, using the Interpersonal Perception Task. All participants received a single intranasal dose of 24 IU oxytocin or placebo, one week apart. Overall, the participants were more accurate in judging intimacy and kinship following the administration of oxytocin, as opposed to a placebo. However, when comparing patients with controls, only the recognition of kinship improved significantly in the patient group, whereas no such effect was observed in the control group or in the recognition of intimacy in either group. This is one of the first studies to demonstrate that social perception in schizophrenia can be improved by the administration of oxytocin and that patients show a greater treatment effect than controls.

Asymmetry in the dorsolateral prefrontal cortex and aggressive behavior: a continuous theta-burst magnetic stimulation study.

Aggressive behavior is aimed at causing damage or pain to another individual. Aggression has been associated with structural and functional deficits in numerous brain areas, including the dorsolateral region of the prefrontal cortex (DLPFC), typically related to inhibition and impulse control. In this study, we used inhibitory continuous theta-burst magnetic stimulation (cTBS) to explore the role of the right and left DLPFC in aggression. Sixteen healthy right-handed volunteers underwent two sessions involving random, real and sham, right and left DLPFC stimulations. These sessions were followed by the Social Orientation Paradigm (SOP), a monetary task that was specially designed to assess participants' aggressive tendencies by measuring the patterns of their reactive aggression (a response to a perceived provocation) and proactive aggression (an aggressive act with goal-oriented purposes). Results indicate that using cTBS to target the left DLPFC was associated with a greater increase in aggressive responses than right DLPFC stimulation. This pattern of results was found for both reactive and proactive types of aggressive reactions. It is concluded that DLPFC asymmetry is involved in modulating reactive and proactive aggression. Our results are in line with recent studies suggesting that the left DLPFC plays a major role in aggressive behavior.

Transcranial magnetic stimulation of the ventromedial prefrontal cortex impairs theory of mind learning.

Imaging and lesion studies indicate that the prefrontal cortex plays a prominent role in mediating theory of mind (ToM) functioning. Particularly, the ventromedial prefrontal cortex (VMPFC) appears to be involved in mediating ToM functioning. This study utilized slow repetitive transcranial magnetic stimulation (rTMS) over the VMPFC in 13 healthy subjects in order to test whether normal functioning of the VMPFC is necessary for ToM functioning. We found that rTMS to the VMPFC, but not sham-rTMS, significantly disrupted ToM learning. Performance on a control task, not involving affective ToM functioning, was not significantly altered after applying rTMS to the VMPFC or sham-rTMS. In an additional experiment, rTMS to the vertex did not significantly affect ToM learning, confirming specificity of the VMPFC region. These findings indicate that the VMPFC is critical for intact ToM learning and shed further light on the concept and localization of ToM in particular and empathic functioning in general.

Projecting memories: the role of the hippocampus in emotional mentalizing.

Humans have a striking tendency to use past autobiographical events to understand their own behavior. However, it is unknown if we use our own memories to understand others. To assess the role of autobiographical memory in mentalizing we examined the contribution of memory structures, specifically the hippocampus, to emotional judgment of others. Subjects were scanned while making emotional judgments regarding themselves, and protagonists deemed similar to or dissimilar from themselves. Results indicated a significant correlation between rating of the self and the similar protagonists, particularly for the events subjects recalled from their past. Furthermore, we found an interaction between similarity and recollection so that only for events subjects recalled from their past, the hippocampus reacted differently for judgments regarding the self versus dissimilar others, but not for self versus similar others. These results suggest that people actually use their own repertoire of memories and project internal self knowledge while making emotional judgments regarding others. It is speculated that mentalizing is modulated by memories of similar past events and depends on the protagonist we face.

The origins of originality: the neural bases of creative thinking and originality.

Although creativity has been related to prefrontal activity, recent neurological case studies postulate that patients who have left frontal and temporal degeneration involving deterioration of language abilities may actually develop de novo artistic abilities. In this study, we propose a neural and cognitive model according to which a balance between the two hemispheres affects a major aspect of creative cognition, namely, originality. In order to examine the neural basis of originality, that is, the ability to produce statistically infrequent ideas, patients with localized lesions in the medial prefrontal cortex (mPFC), inferior frontal gyrus (IFG), and posterior parietal and temporal cortex (PC), were assessed by two tasks involving divergent thinking and originality. Results indicate that lesions in the mPFC involved the most profound impairment in originality. Furthermore, precise anatomical mapping of lesions indicated that while the extent of lesion in the right mPFC was associated with impaired originality, lesions in the left PC were associated with somewhat elevated levels of originality. A positive correlation between creativity scores and left PC lesions indicated that the larger the lesion is in this area the greater the originality. On the other hand, a negative correlation was observed between originality scores and lesions in the right mPFC. It is concluded that the right mPFC is part of a right fronto-parietal network which is responsible for producing original ideas. It is possible that more linear cognitive processing such as language, mediated by left hemisphere structures interferes with creative cognition. Therefore, lesions in the left hemisphere may be associated with elevated levels of originality.

The effect of intranasal administration of oxytocin on fear recognition.

The oxytocinergic system has recently been placed amongst the most promising targets for various psychiatric treatments due to its role in prosocial behavior and anxiety reduction. Although recent studies have demonstrated a general effect of administration of oxytocin on emotion recognition, no study to date has examine the effect of oxytocin on each emotion separately. In the present study, a double-blind placebo-controlled crossover design was used in a dynamic facial expression task, in order to assess the effects of administration of oxytocin on emotion recognition. A single dose of oxytocin or a placebo was administered intranasally to 27 healthy male subjects 45 min prior to task performance. The results showed that a single intranasal administration of oxytocin, as opposed to the placebo, improved the subjects' ability to recognize fear, but not other emotions. These results suggest a specific role for oxytocin in fear recognition, which could be relevant for clinical disorders that manifest deficits in processing emotional facial expressions, particularly fear.