Shared attention experiments examine the potential differences in function or behavior when stimuli are experienced alone or in the presence of others, and when simultaneous attention of the participants to the same stimulus or set is involved. Previous work has found enhanced reactions to emotional stimuli in social situations, yet these changes might represent enhanced communicative or motivational purposes. This study examines whether viewing emotional stimuli in the presence of another person influences attention to or memory for the stimulus. Participants passively viewed emotionally-valenced stimuli while completing another task (counting flowers). Each participant performed this task both alone and in a shared attention condition (simultaneously with another person in the same room) while EEG signals were measured. Recognition of the emotional pictures was later measured. A significant shared attention behavioral effect was found in the attention task but not in the recognition task. Compared to event-related potential responses for neutral pictures, we found higher P3b response for task relevant stimuli (flowers), and higher Late Positive Potential (LPP) responses for emotional stimuli. However, no main effect was found for shared attention between presence conditions. To conclude, shared attention may therefore have a more limited effect on cognitive processes than previously suggested.

There is an ongoing debate concerning the contribution of different aspects of empathy to achieving an accurate understanding of others. In this study, we aimed to better comprehend the roles of experience sharing and mentalizing using a modified empathic-accuracy task. We analyzed the unique contribution of each of these mechanisms with an explicit cognitive report as well as an affective physiological synchrony measurement. First, we recorded the emotional autobiographical stories told by participants (“targets”, N = 28). Then, the targets watched their own videos as their heart rate (HR) was measured, and they reported on both a continuous and a discrete emotion scale what they felt while relaying the story. Next, we collected HR data from new participants (“observers”, N = 72) as they similarly rated the targets’ valence and discrete emotional states. In order to test the contribution of sensorimotor cues and contextual cues to empathic accuracy, observers viewed some videos with audio, others without audio, and listened to a third set of only the audio. We hypothesized that empathic accuracy—a cognitive measure that is a proxy for mentalizing and is operationalized by the correlation between a target’s reported emotions and an observer’s inference of those emotions—would be greater when linguistic information is present. We also hypothesized that physiological synchrony, a proxy for experience sharing, would be greater in the video-only condition, which was limited to sensorimotor cues to infer the other’s emotional state. Indeed, we found that empathic accuracy was greater when auditory information was present, and that HR synchrony was more prevalent when visual cues were presented alone. Having both information streams together did not enhance accuracy, yet it was the only condition in which both behavioral empathic-accuracy measures correlated with HR synchrony. This study provides evidence that separate experience sharing and mentalizing pathways are active in the same task.

Empathy, broadly defined as the ability to understand the other and to share others’ emotions, motivates prosocial behavior and underlies successful interpersonal relations. Dysfunctions in this ability may cause fundamental difficulties in social communication. Empathy has been measured in various ways, from self-report questionnaires to laboratory objective performance tests. Empathic accuracy (EA), i.e., the ability to accurately empathize, is measured using more complex and ecological paradigms, such as asking participants to infer filmed interactions, or having people narrate personal emotional stories then assessing the correspondence between the perceiver and the target of empathy as the criteria for empathic ability. This measure is particularly useful in the study of clinical populations, where deconstructing the multifaceted concept of empathy may contribute to a more complete understanding of specific clinical profiles. This paper presents a scoping review of the literature on EA in clinical populations, and on EA and clinical traits and states in nonclinical or high-risk populations. Following an exhaustive literature search, 34 studies were found eligible to be included in this review. The largest category was studies focused on EA in people with schizophrenia (31%; 11 papers), followed by studies focused on EA in autism spectrum disorders (ASD) and autistic traits in a nonclinical population (22%; 8 papers). Studies were also found on EA and depression tendencies, psychopathy, social anxiety, behavior disorders, and personality disorders, and a few other clinical conditions. The included studies varied on research aims, designs, sample sizes, and male:female ratios. The overall synthesized results suggest that EA is reduced in schizophrenia and ASD. In other clinical populations, the number of studies was very limited. We urge researchers to further examine EA in these less-studied populations. The review reveals a general underrepresentation of female participants in studies on EA in clinical populations. We suggest that future research address understudied clinical populations, such as those diagnosed with psychopathy. Subject, target, and situational variables should also be considered, with special attention to gender differences (and similarities), the association between EA abilities and adaptive functioning, and the study of individuals with clinical conditions as targets, not just observers, in EA tasks.

Embodied theories of cognition emphasize the central role of sensorimotor transformations in the representation of others’ actions. Support for these theories is derived from the discovery of the mirror neuron system (MNS) in primates, from noninvasive techniques in humans, and from a limited number of intracranial studies. To understand the neural dynamics of the human MNS, more studies with precise spatial and temporal resolutions are essential. We used electrocorticography to define activation patterns in sensorimotor, parietal and/or frontal neuronal populations, during a viewing and grasping task. Our results show robust high gamma activation for both conditions in classic MNS sites. Furthermore, we provide novel evidence for 2 different populations of neurons: sites that were only active for viewing and grasping (“pure mirroring”) and sites that were also active between viewing and grasping, and perhaps serve a more general attentional role. Lastly, a subgroup of parietal electrodes showed earlier peaks than all other regions. These results highlight the complexity of spatial-temporal patterns within the MNS and provide a critical link between single-unit research in monkeys and noninvasive techniques in human.

Personal space, defined as the distance individuals choose to maintain between themselves and others, is an indicator of affiliation and closeness. Most paradigms that measure personal space preferences involve explicit choice and therefore fail to examine the implicit aspects of such preferences. In the current study, we sought to investigate an implicit form of interpersonal space that is more closely related to real-life situations involving affiliation. We studied the effects of oxytocin (OT) on neural networks that involve affiliation and tested the impact on personal space preferences. In a double-blind placebo-controlled study, we asked participants to choose between two rooms that differed only in the distances between two stimuli. The stimuli were either social stimuli (two chairs) or non-social stimuli (table and plant). The behavioral results showed that OT caused participants to choose a closer space in social blocks but did not affect their choices in non-social blocks. Imaging results revealed an interaction between stimulus and treatment (OT/PL) in the dorsal striatum, an area that is related to approach motivation and is part of the reward circuitry. Specifically, OT increased activity in the dorsal striatum in the social blocks and decreased this activity in the non-social blocks. The results of the study strengthen the social salience theory regarding OT, indicating that OT does not uniformly affect all social responses and that context has a determining impact on our behavior.

Humans are highly social beings that interact with each other on a daily basis. In these complex interactions, we get along by being able to identify others’ actions and infer their intentions, thoughts and feelings. One of the major theories accounting for this critical ability assumes that the understanding of social signals is based on a primordial tendency to simulate observed actions by activating a mirror neuron system. If mirror neuron regions are important for action and emotion recognition, damage to regions in this network should lead to deficits in these domains. In the current behavioural and EEG study, we focused on the lateral prefrontal cortex including dorsal and ventral prefrontal cortex and utilized a series of task paradigms, each measuring a different aspect of recognizing others’ actions or emotions from body cues. We examined 17 patients with lesions including (n = 8) or not including (n = 9) the inferior frontal gyrus, a core mirror neuron system region, and com

Interpersonal space is a nonverbal indicator of affiliation and closeness. In this study we investigated the effects of oxytocin (OT), a neuropeptide known for its social role in humans, on interpersonal space. In a double blind placebo controlled study we measured the effect of intranasal OT on the personal distance preferences of different familiar (friend) and unfamiliar (stranger) protagonists. Behavioral results showed that participants preferred to be closer to a friend than to a stranger. Intranasal OT was associated with an overall distancing effect, but this effect was significant for the stranger and not for the friend. The imaging results showed interactions between treatment (OT, placebo) and protagonist (friend, stranger) in regions that mediate social behavior including the dorsomedial prefrontal cortex (dmPFC), a region associated with the mentalizing system. Specifically, OT increased activity in the dmPFC when a friend approached the participants but not when a stranger approached. The results indicate that the effect of OT on interpersonal space greatly depends on the participant’s relationship with the protagonist. This supports the social salience theory, according to which OT increases the salience of social cues depending on the context.

Although we encounter numerous expressive faces on a daily basis, those that are not aimed at us will often be disregarded. Facial expressions aimed at our direction appear far more relevant and evoke an engaging affective experience, while the exact same expressions aimed away from us may not. While the importance of expression directionality is intuitive and commonplace, the neural mechanisms underlying this phenomenon are largely unknown. In the current study we measured EEG mu rhythm suppression, an established measure of mirror neuron activity, while participants viewed short video clips of dynamic facial expressions. Critically, the videos portrayed facial emotions which turned towards or away from the viewer, thus manipulating their degree of social relevance. Mirroring activity increased as a function of social relevance such that expressions turning toward the viewer resulted in increased sensorimotor activation (i.e., stronger mu suppression) compared to identical expressions turning away from the viewer. Additional analyses confirmed that expressions turning toward the viewer were perceived as more relevant and engaging than expressions turning away from the viewer, a finding not explained by perceived intensity or recognition accuracy. Mirror sensorimotor mechanisms may play a key role in determining the relevance of perceived facial expressions.

One of the leading hypotheses regarding the mechanism underlying the social effects of oxytocin (OT) is the “social salience hypothesis”, which proposes that OT alters the attentional salience of social cues in a context-dependent manner. Recently, OT was implicated in the process of anthropomorphism; specifically, OT was found to increase the tendency to ascribe social meaning to inanimate stimuli. However, the precise component of social interaction that contributes to this effect remains unclear. Because OT plays a role in the response to touch, whether or not objects are touching in a social context may represent the prominent trigger. Given that OT plays a major role in both anthropomorphism and touch, it is reasonable to assume that OT enhances anthropomorphism specifically for non-human touch, further clarifying its role in altering the perceptual salience of social cues. Here, we examined whether intranasal delivery of OT influences anthropomorphism for touch in inanimate objects. To that end, we implicitly measured the emotional reactions of participants (N = 51) to photos that depicted two humans or two inanimate objects either touching or not touching. We asked them to rate whether they will include each photo in an emotional album and found that OT treatment increased the likelihood of inclusion in an emotional album to photos that contain touch, particularly between inanimate objects. In a follow-up experiment we found that the more human the inanimate objects were perceived, the more included they were in the emotional album. Our findings demonstrate that OT can enhance the social meaning of touch between two inanimate objects and advance our understanding of the mechanisms underlying the ability of OT to anthropomorphize environmental cues.

Interpersonal distance is central to communication and complex social behaviors but the neural correlates of interpersonal distance preferences are not defined. Previous studies suggest that damage to the orbitofrontal cortex (OFC) is associated with impaired interpersonal behavior. To examine whether the OFC is critical for maintaining appropriate interpersonal distance, we tested two groups of patients with OFC damage: Patients with OFC lesions and patients with behavioral variant frontotemporal dementia. These two groups were compared to healthy controls and to patients with lesions restricted to the dorsolateral prefrontal cortex. Only patients with OFC damage showed abnormal interpersonal distance preferences, which were significantly different from both controls and patients with dorsolateral prefrontal damage. The comfortable distances these patients chose with strangers were significantly closer than the other groups and resembled distances normally used with close others. These results shed light on the role of the OFC in regulating social behavior and may serve as a simple diagnostic tool for dementia or lesion patients.

What determines how close you choose to stand to someone? Why do some people prefer farther distances than others? We hypothesized that an important factor is one’s sensory sensitivity level, i.e. how sensitive one is to nearby visual stimulation, noise, touch or smell. This study characterizes the behavioral, hormonal and electrophysiological metrics of interpersonal distance (IPD) preferences in relation to levels of sensory sensitivity. Using both an ecologically realistic task and electroencephalogram (EEG), we found that sensory sensitivity levels predicted IPD preferences, such that the more sensitive one is the farther distance they prefer. Furthermore, electrophysiological evidence revealed that individuals with higher sensory sensitivity show more alpha suppression for approaching stimuli, strengthening the notion that early sensory cortical excitability is involved in one’s social decision of how close to stand to another. The results provide evidence that a core human metric of social interaction is influenced by individual levels of sensory sensitivity.

Working memory (WM) and empathy are core issues in cognitive and social science, respectively. However, no study so far has explored the relationship between these two constructs. Considering that empathy takes place based on the others’ observed experiences, which requires extracting the observed dynamic scene into WM and forming a coherent representation, we hypothesized that a sub-type of WM capacity, i.e., WM for biological movements (BM), should predict one’s empathy level. Therefore, WM capacity was measured for three distinct types of stimuli in a change detection task: BM of human beings (BM; Experiment 1), movements of rectangles (Experiment 2), and static colors (Experiment 3). The first two stimuli were dynamic and shared one WM buffer which differed from the WM buffer for colors; yet only the BM conveyed social information. We found that BM-WM capacity was positively correlated with both cognitive and emotional empathy, with no such correlations for WM capacity of movements of rectangles or of colors. Thus, the current study is the first to provide evidence linking a specific buffer of WM and empathy, and highlights the necessity for considering different WM capacities in future social and clinical research.

Long-term deprivation of normal visual inputs can cause perceptual impairments at various levels of visual function, from basic visual acuity deficits, through mid-level deficits such as contour integration and motion coherence, to high-level face and object agnosia. Yet it is unclear whether training during adulthood, at a post-developmental stage of the adult visual system, can overcome such developmental impairments. Here, we visually trained LG, a developmental object and face agnosic individual. Prior to training, at the age of 20, LG’s basic and mid-level visual functions such as visual acuity, crowding effects, and contour integration were underdeveloped relative to normal adult vision, corresponding to or poorer than those of 5–6 year olds (Gilaie-Dotan, Perry, Bonneh, Malach & Bentin, 2009). Intensive visual training, based on lateral interactions, was applied for a period of 9 months. LG’s directly trained but also untrained visual functions such as visual acuity, crowding, binocular stereopsis and also mid-level contour integration improved significantly and reached near-age-level performance, with long-term (over 4 years) persistence. Moreover, mid-level functions that were tested post-training were found to be normal in LG. Some possible subtle improvement was observed in LG’s higher-order visual functions such as object recognition and part integration, while LG’s face perception skills have not improved thus far. These results suggest that corrective training at a post-developmental stage, even in the adult visual system, can prove effective, and its enduring effects are the basis for a revival of a developmental cascade that can lead to reduced perceptual impairments.

An inherent feature of social interactions is the use of social space or interpersonal distance—the space between one individual and another. Because social deficits are core symptoms of Autistic Spectrum Disorder (ASD), we hypothesized that individuals on this spectrum will exhibit abnormal interpersonal distance preferences. The literature on interpersonal distance in ASD is not conclusive. While some studies show preferences for closer distances among this group, others show preferences for farther distances than controls. A common symptom of ASD that may explain the variance in responses to interpersonal distance in this population is social anxiety (SA), which has been shown to correlate with interpersonal distance preferences. In the current study, we investigated interpersonal distance preferences in a group of individuals with ASD using both behavioral and ERP measures. We found greater variance in interpersonal distance preferences in the ASD group than in the control group. Furthermore, we showed that this variance can be explained by differences in SA level and can be predicted by the N1 amplitude, an early ERP component related to attention and discrimination processes. These results hint at the early sensory and attentional processes that may be affecting higher social behaviors, both in subclinical and in clinical populations.

The space between people, or ‘interpersonal distance’, creates and defines the dynamics of social interactions and is a salient cue signaling responsiveness and feeling comfortable. This distance is implicit yet clearly felt, especially if someone stands closer or farther away than expected. Increasing evidence suggests that Oxytocin (OT) serves as a social hormone in humans, and that one of its roles may be to alter the perceptual salience of social cues. Considering that empathic ability may shape the way individuals process social stimuli, we predicted that OT will differentially affect preferred interpersonal distance depending on individual differences in empathy. Participants took part in two interpersonal distance experiments: In the first, they had to stop a (computer visualized) protagonist when feeling most comfortable; in the second, they were asked to choose the room in which they would later discuss intimate topics with another. Both experiments revealed an interaction between the effect of OT and empathy level. Among highly empathic individuals, OT promoted the choice of closer interpersonal distances. Yet, OT had an opposite effect on individuals with low empathic traits. We conclude that the enhancement of social cues following OT administration may have opposite effects on individuals with different empathic abilities.

Mu suppression is the attenuation of EEG power in the alpha frequency range (8-12 Hz), recorded over the sensorimotor cortex during execution and observation of motor actions. Based on this dual characteristic mu suppression is thought to signalize activation of a human analogue of the mirror neuron system (MNS) found in macaque monkeys. However, much uncertainty remains concerning its specificity and full significance. To further explore the hypothesized relationship between mu suppression and MNS activation, we investigated how it is affected by damage to cortical regions, including areas where the MNS is thought to reside. EEG was recorded in 33 first-event stroke patients during observation of video clips showing reaching and grasping hand movements. We examined the modulation of EEG oscillations at central and occipital sites, and analyzed separately the lower (8-10 Hz) and higher (10-12 Hz) segments of the alpha/mu range. Suppression was determined relative to observation of a non-biological movement. Normalized lesion data were used to investigate how damage to regions of the fronto-parietal cortex affects the pattern of suppression. The magnitude of mu suppression during action observation was significantly reduced in the affected hemisphere compared to the unaffected hemisphere. Differences between the hemispheres were significant at central (sensorimotor) sites but not at occipital (visual) sites. Total hemispheric volume loss did not correlate with mu suppression. Suppression in the lower mu range in the unaffected hemisphere (C3) correlated with lesion extent within the right inferior parietal cortex. Our lesion study supports the role of mu suppression as a marker of MNS activation, confirming previous studies in normal subjects.

The space between people, or interpersonal distance, creates and defines the dynamics of social interactions. Given that invasion of one’s interpersonal space may trigger threat and anxiety, a critical question is if high vulnerability to social anxiety (SA) is associated with avoidance and attentional biases when anticipating invasion to one’s interpersonal space. Therefore, the current study sought to examine the behavioral mechanisms, time course and neural correlates underlying the threat of interpersonal distance invasion with a focus on different SA levels, using both a behavioral and an ERP experiment. Preferred interpersonal distance was assessed using a paradigm that involves responding to different virtual protagonists (friend or stranger) approaching the participant by indicating where one would like the protagonist to stop. In addition, participants’ level of social anxiety was measured. The behavioral experiment indicated that levels of SA predicted one’s preferred interpersonal distance such that higher SA individuals preferred further distance from a stranger. At the neural level, across groups, early (N1) but not late (LPP) differences were found between stranger and friend conditions. Importantly, SA individuals were characterized by attenuated early ERP responses, suggesting less attentional resources allocated to social stimuli. The results suggest that high SA individuals feel discomfort earlier than others in social engagement, which may lead them to stand further away, thus creating less communicative social interactions.