Publications

In Press
Choshen-Hillel, S., Sadras, I., Gordon-Hecker, T., Genzer, S., Rekhtman, D., Caruso, E. M., Clements, K. L., et al. (In Press). The effects of physicians’ night shifts on their empathy for patients’ pain and subsequent analgesic prescription. Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences , 119 (27), e2200047119. Publisher's VersionAbstract
*shared senior author
Adequate pain management is one of the biggest challenges of the modern healthcare system. Physician perception of patient subjective pain, which is crucial to pain management, is susceptible to a host of potential biases. Here we explore the timing of physicians’ work as a previously unrecognized source of systematic bias in pain management. We hypothesized that during night shifts, sleep deprivation, fatigue, and stress would reduce physicians’ empathy for others’ pain, leading to underprescription of analgesics for patient pain relief. In study 1, 67 resident physicians, either following a night shift or not, performed empathy for pain assessment tasks and simulated patient scenarios in laboratory conditions. As predicted, following a night shift, physicians showed reduced empathy for pain. In study 2, we explored this phenomenon in medical decisions in the field. We analyzed three emergency department datasets from Israel and the United States that included discharge notes of patients arriving with pain complaints during 2013 to 2020 (n = 13,482). Across all datasets, physicians were less likely to prescribe an analgesic during night shifts (compared to daytime shifts) and prescribed fewer analgesics than generally recommended by the World Health Organization. This effect remained significant after adjusting for patient, physician, type of complaint, and emergency department characteristics. Underprescription for pain during night shifts was particularly prominent for opioids. We conclude that night shift work is an important and previously unrecognized source of bias in pain management, likely stemming from impaired perception of pain. We consider the implications for hospitals and other organizations employing night shifts.
2022
Rum, Y., Genzer, S., Markovitch, N., Jenkins, J., Perry, A., & Knafo-Noam, A. (2022). Are there positive effects of having a sibling with special needs? Empathy and prosociality of twins of children with non-typical development. Child Development, Child Development , 93 (4), 1121-1128. Publisher's VersionAbstract
This study examined whether typically developing (TD) twins of non-TD children demonstrate enhanced empathy and prosociality. Of 778 Hebrew-speaking Israeli families who participated in a twin study, 63 were identified to have a non-TD child with a TD twin, and 404 as having both twins TD. TD twins of non-TD children (27% males) were compared to the rest of the cohort of TD children (46% males) on measures of empathy and prosociality. Participants were 11 years old. TD twins of non-TD children scored significantly higher than TD twins of TD children in a measure of cognitive empathy (d = .43). No differences were found in emotional empathy and prosociality. The specificity of the positive effect on cognitive empathy is discussed.
Van Bavel, J. J., Cichocka, A., Capraro, V., Sjåstad, H., Nezlek, J. B., Pavlović, T., Alfano, M., et al. (2022). National identity predicts public health support during a global pandemic. Nature Communications, Nature Communications , 13 (1). Publisher's VersionAbstract
Changing collective behaviour and supporting non-pharmaceutical interventions is an important component in mitigating virus transmission during a pandemic. In a large international collaboration (Study 1, N = 49,968 across 67 countries), we investigated self-reported factors associated with public health behaviours (e.g., spatial distancing and stricter hygiene) and endorsed public policy interventions (e.g., closing bars and restaurants) during the early stage of the COVID-19 pandemic (April-May 2020). Respondents who reported identifying more strongly with their nation consistently reported greater engagement in public health behaviours and support for public health policies. Results were similar for representative and non-representative national samples. Study 2 (N = 42 countries) conceptually replicated the central finding using aggregate indices of national identity (obtained using the World Values Survey) and a measure of actual behaviour change during the pandemic (obtained from Google mobility reports). Higher levels of national identification prior to the pandemic predicted lower mobility during the early stage of the pandemic (r = −0.40). We discuss the potential implications of links between national identity, leadership, and public health for managing COVID-19 and future pandemics.
Jospe, K., Genzer, S., Ong, D., Zaki, J., Soroker, N., & Perry, A. (2022). Impaired empathic accuracy following damage to the left hemisphere. Biological Psychology, Biological Psychology , 172. Publisher's VersionAbstract
Failing to understand others accurately can be extremely costly. Unfortunately, events such as strokes can lead to a decline in emotional understanding. Such impairments have been documented in stroke patients and are widely hypothesized to be related to right-hemisphere lesions, as well as to the amygdala, and are thought to be driven in part by attentional biases, for example, less fixation on the eyes. Notably, most of the previous research relied on measurements of emotional understanding from simplified cues, such as facial expressions or prosody. We hypothesize that chronic damage to the left hemisphere could hinder empathic accuracy and emotion recognition in naturalistic social settings that require complex language comprehension, even after a patient regains core language capacities. To assess this notion, we use an empathic accuracy task and eye-tracking measurements with chronic stroke patients with either right (N = 13) or left (N = 11) hemispheric damage—together with aged-matched controls (N = 15)—to explore the patients’ understanding of others’ affect inferred from stimuli that separates audio and visual cues. While we find that patients with right-hemisphere lesions showed visual attention bias compared to the other two groups, we uncover a disadvantage for patients with left-hemisphere lesions in empathic accuracy, especially when only auditory cues are present. These results suggest that patients with left-hemisphere damage have long-lasting difficulties comprehending real-world complex emotional situations.
Kassem, N., Rum, Y., & Perry, A. (2022). To feel and talk in a language of conflict: Distinctive emotional experience and expression of bilinguals in a conflict area. Journal of Multilingual and Multicultural Development, Journal of Multilingual and Multicultural Development , 1-18. Publisher's VersionAbstract
Research conducted on emotionality in bilinguals suggests that language use modulates emotional expression. The current study examines bilingual disadvantaged minority members’ emotional experience and expression as shaped by the group relations in a conflict area. We hypothesised that, in general, greater emotionality will be found in one’s native language. Moreover, since the second language is imposed and acquired in a negative context, there may be differential effects on negative and positive language. A novel ecological paradigm was used: Twenty-eight Palestinian citizens of Israel were videotaped while recounting emotional stories in both Arabic (L1) and Hebrew (L2), resulting in 212 videos. Two studies followed: In Study 1 we compared participants’ emotional ratings (1a) and analyzed the content of emotional expression (1b). In Study 2, American participants rated emotional expressiveness. In Study 1, an interaction effect was found between language and valence, with less positive emotions and expressions in L2. In Study 2, a general difference in expressiveness was found in favour of L1. These studies show an effect of power disparities on the emotional load of the second language, thus highlighting the emotional costs of using a second language acquired in a conflict area.
Genzer, S., Ong, D. C., Zaki, J., & Perry, A. (2022). Mu rhythm suppression over sensorimotor regions is associated with greater empathic accuracy. Social Cognitive & Affective Neuroscience. Social Cognitive & Affective Neuroscience, Social Cognitive & Affective Neuroscience. Publisher's VersionAbstract
When people encounter others’ emotions, they engage multiple brain systems, including parts of the sensorimotor cortex associated with motor simulation. Simulation-related brain activity is commonly described as a ‘low-level’ component of empathy and social cognition. It remains unclear whether and how sensorimotor simulation contributes to complex empathic judgments. Here, we combine a naturalistic social paradigm with a reliable index of sensorimotor cortex-based simulation: electroencephalography suppression of oscillatory activity in the mu frequency band. We recruited participants to watch naturalistic video clips of people (‘targets’) describing emotional life events. In two experiments, participants viewed these clips (i) with video and sound, (ii) with only video or (iii) with only sound and provided continuous ratings of how they believed the target felt. We operationalized ‘empathic accuracy’ as the
2021
Llorens, A., Tzovara, A., Bellier, L., & et al,. (2021). Gender bias in academia: A lifetime problem that needs solutions. Neuron, Neuron , 109 (13), 2047-2074. Publisher's VersionAbstract
Despite increased awareness of the lack of gender equity in academia and a growing number of initiatives to address issues of diversity, change is slow, and inequalities remain. A major source of inequity is gender bias, which has a substantial negative impact on the careers, work-life balance, and mental health of underrepresented groups in science. Here, we argue that gender bias is not a single problem but manifests as a collection of distinct issues that impact researchers’ lives. We disentangle these facets and propose concrete solutions that can be adopted by individuals, academic institutions, and society.
Weiblen, R., Mairon, N., Krach, S., & et al,. (2021). The influence of anger on empathy and theory of mind. PloS one, PloS one , 16 (7), e0255068. Publisher's VersionAbstract
Social cognition allows humans to understand and predict other people’s behavior by inferring or sharing their emotions, intentions and beliefs. Few studies have investigated the impact of one’s own emotional state on understanding others. Here, we tested the effect of being in an angry state on empathy and theory of mind (ToM). In a between-groups design we manipulated anger status with different paradigms in three studies (autobiographical recall (N = 45), negative feedback (N = 49), frustration (N = 46)) and checked how this manipulation affected empathic accuracy and performance in the EmpaToM. All paradigms were successful in inducing mild anger. We did not find the expected effect of anger on empathy or ToM performance but observed small behavioral changes. Together, our results validate the use of three different anger induction paradigms and speak for rather weak behavioral effects of mild state anger on empathy and ToM.
Israelashivili, J., & Perry, A. (2021). Nuancing perspective: Feedback shapes the understanding of another’s emotion. Social Psychology, Social Psychology , 52 (4), 238-249. Publisher's VersionAbstract
Two experiments manipulated participants’ familiarity with another person and examined their performance in future understanding of that person’s emotions. To gain familiarity, participants watched several videos of the target sharing experiences and rated her emotions. In the Feedback condition, perceivers learned about the actual emotions the target felt. In the Control condition, perceivers completed identical recognition tasks but did not know the target’s own emotion ratings. Studies (N total= 398; one preregistered) found that the Feedback group was more accurate than the Control in future understanding of the target’s emotions. Results provide a proof-of-concept demonstration that brief preliminary learning about past emotional experiences of another person can give one a more accurate understanding of the person in the future.(PsycInfo Database Record (c) 2021 APA, all rights reserved.
2020
Jospe, K., Genzer, S., klein Selle, N., Ong, D., Zaki, J., & Perry, A. (2020). The contribution of linguistic and visual cues to physiological synchrony and empathic accuracy. Cortex, Cortex , 132, 296-308. Publisher's VersionAbstract
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.
Mairon, N., Nahum, M., Stolk, A., Knight, R. T., & Perry, A. (2020). Behavioral and EEG Measures Show no Amplifying Effects of Shared Attention on Attention or Memory. Scientific Reports, Scientific Reports , 10 (1), 1-11. Publisher's VersionAbstract
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.
Rum, Y., & Perry, A. (2020). Empathic Accuracy in Clinical Populations. Frontiers in Psychiatry, Frontiers in Psychiatry , 11, 457. Publisher's VersionAbstract
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.
Rubinstein, O., Corem, N., Perry, A., Gold, M., & Shamay-Tsoory, S. (2020). Different neural activations for an approaching friend versus stranger: Linking personal space to numerical cognition. Brain and Behaviour, Brain and Behaviour , 10 (6), e01613. Publisher's VersionAbstract

Introduction

Typically, humans place themselves at a preferred distance from others. This distance is known to characterize human spatial behavior. Here, we focused on neurocognitive conditions that may affect interpersonal distances. The current study investigated whether neurocognitive deficiencies in numerical and spatial knowledge may affect social perception and modulate personal space.

Method

In an event-related potential (ERP) study, university students with developmental dyscalculia (DD) and typically developing control participants were given a computerized version of the comfortable interpersonal distance task, in which participants were instructed to press the spacebar when they began to feel uncomfortable by the approach of a virtual protagonist.

Results

Results showed that students with deficiencies in numerical and spatial skills (i.e., DD) demonstrated reduced variability in their preferred distance from an approaching friend. Importantly, DD showed decreased amplitude of the N1 wave in the friend condition.

Conclusion

These results suggest that people coping with deficiencies in spatial cognition have a less efficient allocation of spatial attention in the service of processing personal distances. Accordingly, the study highlights the fundamental role of spatial neurocognition in organizing social space.

2018
Perry, A., Stiso, J., Chang, E. F., Lin, J. J., Parvizi, J., & Knight, R. T. (2018). Mirroring in the human brain: Deciphering the spatial and temporal patterns of the human mirror neuron system, an ECoG study. Cerebral Cortex, Cerebral Cortex , 3 (28), 1039-1048. Publisher's VersionAbstract
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.
Cohen, D., Perry, A., Mayseless, N., Kleinmintz, O., & Shamay-Tsoory, S. (2018). The role of oxytocin in implicit personal space regulation - an fMRI study. Psychoneuroendocrinology, Psychoneuroendocrinology , 91, 206-215. Publisher's VersionAbstract
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.
2017
Ensenberg, N., Perry, A., & Aviezer, H. (2017). Are you looking at me? Mu suppression modulation by facial expression direction. Cognitive Affective & Behavioral Neuroscience, Cognitive Affective & Behavioral Neuroscience , 17 (1), 174-184. Publisher's VersionAbstract
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.
Perry, A., Saunders, S. N., Stiso, J., Dewar, C., Lubell, J., Meling, T. R., Solbakk, A. - K., et al. (2017). Effects of prefrontal cortex damage on emotion understanding: EEG and behavioural evidence. Brain: A Journal of Neurology, Brain: A Journal of Neurology , 140 (4), 1086 - 1099. Publisher's VersionAbstract
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
Cohen, D., Perry, A., Gilam, G., Mayseless, N., Gonen, T., Hendler, T., & Shamay-Tsoory, S. G. (2017). The role of oxytocin in modulating interpersonal space: A pharmacological fMRI study. Psychoneuroendocrinology, Psychoneuroendocrinology , 76, 77-83. Publisher's VersionAbstract
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.
2016
Peled-Avron, L., Perry, A., & Shamay-Tsoory, S. G. (2016). Where does one stand: a biological account of preferred interpersonal distance. Social Cognitive and Affective Neuroscience, Social Cognitive and Affective Neuroscience , 11 (2), 317–326. Publisher's VersionAbstract
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.
Gao, Z., Ye, T., Shen, M., & Perry, A. (2016). Working memory capacity of biological movements predicts empathy traits. Psychonomic Bulletin & Review, Psychonomic Bulletin & Review , 23 (2), 468-475. Publisher's VersionAbstract
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.