Dimitris Xygalatas | University of Connecticut (original) (raw)

Publications by Dimitris Xygalatas

Religions, 2024

This paper investigates socioeconomic variation in motivations for ritual practices among Maurit... more This paper investigates socioeconomic variation in motivations for ritual practices among
Mauritian Hindus. Using cultural domain analysis, we explore individuals’ reported reasons for
engaging in a variety of religious rituals. Our findings demonstrate significant intra-cultural diversity
driven by social stratification. Specifically, we observe that those of lower social standing appear
primarily motivated by existential concerns related to material security and safety, while higher-status
individuals view these practices as platforms for personal and social enrichment, as they are more
preoccupied with self-actualization, spiritual connection, and social affirmation, reflecting a more
abstract engagement with religious practices. Our findings reveal the adaptability of ritual practices
to meet a wide range of human needs across varying life circumstances, as rituals can be differentially
negotiated by individuals within the same cultural context depending on the specific socioecological
niches they occupy. Moreover, they highlight the role of culture as a dynamic and distributed system
with important implications for anthropological theory and practice.

N. Roubekas, D. Xygalatas, L. H. Martin & D. Wiebe (eds.), Studying religion, past and present: essays in honor of Panayotis Pachis, 2024

Journal for the Cognitive Science of Religion, 2024

Evolutionary Human Sciences

Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punit... more Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punitive and monitoring gods that care about moral norms facilitate cooperation. While there is some evidence to suggest that belief in supernatural punishment and monitoring generally induce cooperative behaviour, the effect of a deity's explicitly postulated moral concerns on cooperation remains unclear. Here, we report a pre-registered set of analyses to assess whether perceiving a locally relevant deity as moralistic predicts cooperative play in two permutations of two economic games using data from up to 15 diverse field sites. Across games, results suggest that gods’ moral concerns do not play a direct, cross-culturally reliable role in motivating cooperative behaviour. The study contributes substantially to the current literature by testing a central hypothesis in the evolutionary and cognitive science of religion with a large and culturally diverse dataset using behavioural and et...

Philosophical Transactions of The Royal Society B , 2024

Collective rituals involve the coordination of intentions and actions and have been shown to prom... more Collective rituals involve the coordination of intentions and actions and have been shown to promote the alignment of emotional states and social identities. However, the mechanics of achieving group-level synchrony is yet unclear. We report the results of a naturalistic study in the context of an Islamic congregational prayer that involves synchronous movement. We used wearable devices to capture data on body posture, autonomic responses and spatial proximity to investigate how postural alignment and shared arousal intertwine during this ritual. The findings reveal a dual process at play: postural alignment appears to be more localized, with worshippers synchronizing their movements with their nearest neighbours, while physiological alignment operates on a broader scale, primarily driven by the central role of the religious leader. Our findings underscore the importance of interpersonal dynamics in collective gatherings and the role of physical co-presence in fostering connections among participants, with implications extending to our understanding of group dynamics across various social settings. This article is part of the theme issue 'Minds in movement: embodied cognition in the age of artificial intelligence'.

American Journal of Human Biology, 2024

Collective gatherings are often associated with the alignment of psychophysiological states betwe... more Collective gatherings are often associated with the alignment of psychophysiological states between members of a crowd. While the process of emotional contagion has been studied extensively in dyads as well as at the population level, our understanding of its operation and dynamics as they unfold in real time in real-world group contexts remains limited. Employing a naturalistic design, we investigated emotional contagion in a public religious ritual by

People tend to evaluate information from reliable sources more favourably, but it is unclear exac... more People tend to evaluate information from reliable sources more favourably, but it is unclear exactly how perceivers' worldviews interact with this source credibility effect. In a large and diverse cross-cultural sample (N = 10,195 from 24 countries), we presented participants with obscure, meaningless statements attributed to either a spiritual guru or a scientist. We found a robust global source credibility effect for scientific authorities, which we dub `the Einstein effect': across all 24 countries scientists hold greater authority than spiritual source, even among highly committed religious people, who are relatively also more credulous of nonsense from scientists than they are of nonsense from spiritual gurus. Additionally, individual religiosity predicted a weaker relative preference for the statement from the scientist vs. the spiritual guru, and was more strongly associated with credibility judgments for the guru than the scientist. Independent data on explicit trust...

All over the world, people reason dualistically. We consider it more probable that mental states,... more All over the world, people reason dualistically. We consider it more probable that mental states, such as love, continue after biological death than we think bodily states, such as hunger, will continue. However the extent to which culture affects mind-body dualism remains unclear. Here, we draw on a large and diverse cross-cultural sample (24 countries, N = 10195) to systematically quantify cultural variation in tendencies for mind-body dualism. Our findings replicate previous work suggesting that mind-body dualism is culturally universal. Furthermore, our experiment reveals that religion amplifies dualistic tendencies. At the same time, however, the modal response across most countries was the cessation of all states. In addition, explicit afterlife beliefs were more prevalent than implicit afterlife beliefs (i.e., continuity judgments). Overall, these data suggest that intuitive materialism is the cross-cultural norm, with dualism arising from culturally acquired beliefs.

The relation between religiosity and well-being is one of the most researched topics in the psych... more The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N=10,535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported beta = 0.120). For the second research question, this wa...

Scientific Reports

People face stressors that are beyond their control and that maladaptively perpetuate anxiety. In... more People face stressors that are beyond their control and that maladaptively perpetuate anxiety. In these contexts, rituals emerge as a natural coping strategy helping decrease excessive anxiety. However, mechanisms facilitating these purported effects have rarely been studied. We hypothesized that repetitive and rigid ritual sequences help the human cognitive-behavioral system to return to low-entropy states and assuage anxiety. This study reports a pre-registered test of this hypothesis using a Czech student sample (n = 268). Participants were exposed to an anxiety induction and then randomly assigned to perform one of three actions: ritualized, control, and neutral (no-activity). We assessed the effects of this manipulation on cognitive and physiological anxiety, finding that ritualized action positively affected anxiety decrease, but this decrease was only slightly larger than in the other two conditions. Nevertheless, the between-condition differences in the reduction of physiolo...

Proceedings of the National Academy of Sciences

To address claims of human exceptionalism, we determine where humans fit within the greater mamma... more To address claims of human exceptionalism, we determine where humans fit within the greater mammalian distribution of reproductive inequality. We show that humans exhibit lower reproductive skew (i.e., inequality in the number of surviving offspring) among males and smaller sex differences in reproductive skew than most other mammals, while nevertheless falling within the mammalian range. Additionally, female reproductive skew is higher in polygynous human populations than in polygynous nonhumans mammals on average. This patterning of skew can be attributed in part to the prevalence of monogamy in humans compared to the predominance of polygyny in nonhuman mammals, to the limited degree of polygyny in the human societies that practice it, and to the importance of unequally held rival resources to women’s fitness. The muted reproductive inequality observed in humans appears to be linked to several unusual characteristics of our species—including high levels of cooperation among males...

Evolutionary Human Sciences, 2023

Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punit... more Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punitive and monitoring gods that care about moral norms facilitate cooperation. While there is some evidence to suggest that belief in supernatural punishment and monitoring generally induce cooperative behaviour, the effect of a deity's explicitly postulated moral concerns on cooperation remains unclear. Here, we report a pre-registered set of analyses to assess whether perceiving a locally relevant deity as moralistic predicts cooperative play in two permutations of two economic games using data from up to 15 diverse field sites. Across games, results suggest that gods' moral concerns do not play a direct, cross-culturally reliable role in motivating cooperative behaviour. The study contributes substantially to the current literature by testing a central hypothesis in the evolutionary and cognitive science of religion with a large and culturally diverse dataset using behavioural and ethnographically rich methods.

Scientific Data, 2016

A considerable body of research cross-culturally examines the evolution of religious traditions, ... more A considerable body of research cross-culturally examines the evolution of religious traditions, beliefs and behaviors. The bulk of this research, however, draws from coded qualitative ethnographies rather than from standardized methods specifically designed to measure religious beliefs and behaviors. Psychological data sets that examine religious thought and behavior in controlled conditions tend to be disproportionately sampled from student populations. Some cross-national databases employ standardized methods at the individual level, but are primarily focused on fully market integrated, state-level societies. The Evolution of Religion and Morality Project sought to generate a data set that systematically probed individual level measures sampling across a wider range of human populations. The set includes data from behavioral economic experiments and detailed surveys of demographics, religious beliefs and practices, material security, and intergroup perceptions. This paper describ...

Frontiers in Psychology, 2013

Collective rituals are biologically ancient and culturally pervasive, yet few studies have quanti... more Collective rituals are biologically ancient and culturally pervasive, yet few studies have quantified their effects on participants. We assessed two plausible models from qualitative anthropology: ritual empathy predicts affective convergence among all ritual participants irrespective of ritual role; rite-of-passage predicts emotional differences, specifically that ritual initiates will express relatively negative valence when compared with non-initiates. To evaluate model predictions, images of participants in a Spanish fire-walking ritual were extracted from video footage and assessed by nine Spanish raters for arousal and valence. Consistent with rite-of-passage predictions, we found that arousal jointly increased for all participants but that valence differed by ritual role: fire-walkers exhibited increasingly positive arousal and increasingly negative valence when compared with passengers. This result offers the first quantified evidence for rite of passage dynamics within a highly arousing collective ritual. Methodologically, we show that surprisingly simple and non-invasive data structures (rated video images) may be combined with methods from evolutionary ecology (Bayesian Generalized Linear Mixed Effects models) to clarify poorly understood dimensions of the human condition.

Journal of Cognition and Culture, 2013

Anthropological theories have discussed the efffects of participation in high-arousal rituals in ... more Anthropological theories have discussed the efffects of participation in high-arousal rituals in the formation of autobiographical memory; however, precise measurements for such efffects are lacking. In this study, we examined episodic recall among participants in a highly arousing firewalking ritual. To assess arousal, we used heart rate measurements. To assess the dynamics of episodic memories, we obtained reports immediately after the event and two months later. We evaluated memory accuracy from video footage. Immediately after the event, participants' reports revealed limited recall, low confijidence and high accuracy. Two months later we found more inaccurate memories and higher confijidence. Whereas cognitive theories of ritual have predicted flashbulb memories for highly arousing rituals, we found that memories were strongly suppressed immediately after the event and only later evolved confijidence and detail. Physiological measurements revealed a spectacular discrepancy between actual heart rates and self-reported arousal. This dissociation between subjective reports and objective measurements of arousal is consistent with a cognitive resource depletion model. We argue that expressive suppression may provide a link between individual memories and cultural understandings of high-arousal rituals.

Psychological Science, 2013

PLoS ONE, 2014

Previous research has shown that ideas which violate our expectations, such as schema-inconsisten... more Previous research has shown that ideas which violate our expectations, such as schema-inconsistent concepts, enjoy privileged status in terms of memorability. In our study, memory for concepts that violate cultural (cultural schema-level) expectations (e.g., ''illiterate teacher'', ''wooden bottle'', or ''thorny grass'') versus domain-level (ontological) expectations (e.g., ''speaking cat'', ''jumping maple'', or ''melting teacher'') was examined. Concepts that violate cultural expectations, or counter-schematic, were remembered to a greater extent compared with concepts that violate ontological expectations and with intuitive concepts (e.g., ''galloping pony'', ''drying orchid'', or ''convertible car''), in both immediate recall, and delayed recognition tests. Importantly, concepts related to agents showed a memory advantage over concepts not pertaining to agents, but this was true only for expectation-violating concepts. Our results imply that intuitive, everyday concepts are equally attractive and memorable regardless of the presence or absence of agents. However, concepts that violate our expectations (cultural-schema or domain-level) are more memorable when pertaining to agents (humans and animals) than to non-agents (plants or objects/artifacts). We conclude that due to their evolutionary salience, cultural ideas which combine expectancy violations and the involvement of an agent are especially memorable and thus have an enhanced probability of being successfully propagated.

How do people feel during extreme collective rituals? Despite longstanding speculation, few studi... more How do people feel during extreme collective rituals? Despite longstanding speculation, few studies have attempted to quantify ritual experiences. Using a novel pre/post design, we quantified physiological fluctuations (heart rates) and selfreported affective states from a collective fire-walking ritual in a Mauritian Hindu community. Specifically, we compared changes in levels of happiness, fatigue, and heart rate reactivity among high-ordeal participants (fire-walkers), low-ordeal participants (non-fire-walking participants with familial bonds to fire-walkers) and spectators (unrelated/unknown to the fire-walkers). We observed that fire-walkers experienced the highest increase in heart rate and reported greater happiness post-ritual compared to low-ordeal participants and spectators. Low-ordeal participants reported increased fatigue after the ritual compared to both fire-walkers and spectators, suggesting empathetic identification effects. Thus, witnessing the ritualistic suffering of loved ones may be more exhausting than experiencing suffering oneself. The findings demonstrate that the level of ritual involvement is important for shaping affective responses to collective rituals. Enduring a ritual ordeal is associated with greater happiness, whereas observing a loved-one endure a ritual ordeal is associated with greater fatigue post-ritual.

Religion, Brain & Behavior, 2013

We explore the cognitive effects of three common features of religious interactions: (1) demand f... more We explore the cognitive effects of three common features of religious interactions: (1) demand for the expressive suppression of emotion; (2) exposure to goaldemoted and causally opaque actions; and (3) the presence of a charismatic authority. Using a cognitive resource model of executive function, we argue that these three features affect the executive system in ways that limit the capacity for individual processing of religious events. We frame our analysis in the context of a general assumption that collective rituals facilitate the transmission of cultural ideas. Building on recent experiments, we suggest that these three features increase participants' susceptibility to authoritative narratives and interpretations by preventing individuals from constructing their own accounts of the ritual event.

Religions, 2024

This paper investigates socioeconomic variation in motivations for ritual practices among Maurit... more This paper investigates socioeconomic variation in motivations for ritual practices among
Mauritian Hindus. Using cultural domain analysis, we explore individuals’ reported reasons for
engaging in a variety of religious rituals. Our findings demonstrate significant intra-cultural diversity
driven by social stratification. Specifically, we observe that those of lower social standing appear
primarily motivated by existential concerns related to material security and safety, while higher-status
individuals view these practices as platforms for personal and social enrichment, as they are more
preoccupied with self-actualization, spiritual connection, and social affirmation, reflecting a more
abstract engagement with religious practices. Our findings reveal the adaptability of ritual practices
to meet a wide range of human needs across varying life circumstances, as rituals can be differentially
negotiated by individuals within the same cultural context depending on the specific socioecological
niches they occupy. Moreover, they highlight the role of culture as a dynamic and distributed system
with important implications for anthropological theory and practice.

N. Roubekas, D. Xygalatas, L. H. Martin & D. Wiebe (eds.), Studying religion, past and present: essays in honor of Panayotis Pachis, 2024

Journal for the Cognitive Science of Religion, 2024

Evolutionary Human Sciences

Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punit... more Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punitive and monitoring gods that care about moral norms facilitate cooperation. While there is some evidence to suggest that belief in supernatural punishment and monitoring generally induce cooperative behaviour, the effect of a deity's explicitly postulated moral concerns on cooperation remains unclear. Here, we report a pre-registered set of analyses to assess whether perceiving a locally relevant deity as moralistic predicts cooperative play in two permutations of two economic games using data from up to 15 diverse field sites. Across games, results suggest that gods’ moral concerns do not play a direct, cross-culturally reliable role in motivating cooperative behaviour. The study contributes substantially to the current literature by testing a central hypothesis in the evolutionary and cognitive science of religion with a large and culturally diverse dataset using behavioural and et...

Philosophical Transactions of The Royal Society B , 2024

Collective rituals involve the coordination of intentions and actions and have been shown to prom... more Collective rituals involve the coordination of intentions and actions and have been shown to promote the alignment of emotional states and social identities. However, the mechanics of achieving group-level synchrony is yet unclear. We report the results of a naturalistic study in the context of an Islamic congregational prayer that involves synchronous movement. We used wearable devices to capture data on body posture, autonomic responses and spatial proximity to investigate how postural alignment and shared arousal intertwine during this ritual. The findings reveal a dual process at play: postural alignment appears to be more localized, with worshippers synchronizing their movements with their nearest neighbours, while physiological alignment operates on a broader scale, primarily driven by the central role of the religious leader. Our findings underscore the importance of interpersonal dynamics in collective gatherings and the role of physical co-presence in fostering connections among participants, with implications extending to our understanding of group dynamics across various social settings. This article is part of the theme issue 'Minds in movement: embodied cognition in the age of artificial intelligence'.

American Journal of Human Biology, 2024

Collective gatherings are often associated with the alignment of psychophysiological states betwe... more Collective gatherings are often associated with the alignment of psychophysiological states between members of a crowd. While the process of emotional contagion has been studied extensively in dyads as well as at the population level, our understanding of its operation and dynamics as they unfold in real time in real-world group contexts remains limited. Employing a naturalistic design, we investigated emotional contagion in a public religious ritual by

People tend to evaluate information from reliable sources more favourably, but it is unclear exac... more People tend to evaluate information from reliable sources more favourably, but it is unclear exactly how perceivers' worldviews interact with this source credibility effect. In a large and diverse cross-cultural sample (N = 10,195 from 24 countries), we presented participants with obscure, meaningless statements attributed to either a spiritual guru or a scientist. We found a robust global source credibility effect for scientific authorities, which we dub `the Einstein effect': across all 24 countries scientists hold greater authority than spiritual source, even among highly committed religious people, who are relatively also more credulous of nonsense from scientists than they are of nonsense from spiritual gurus. Additionally, individual religiosity predicted a weaker relative preference for the statement from the scientist vs. the spiritual guru, and was more strongly associated with credibility judgments for the guru than the scientist. Independent data on explicit trust...

All over the world, people reason dualistically. We consider it more probable that mental states,... more All over the world, people reason dualistically. We consider it more probable that mental states, such as love, continue after biological death than we think bodily states, such as hunger, will continue. However the extent to which culture affects mind-body dualism remains unclear. Here, we draw on a large and diverse cross-cultural sample (24 countries, N = 10195) to systematically quantify cultural variation in tendencies for mind-body dualism. Our findings replicate previous work suggesting that mind-body dualism is culturally universal. Furthermore, our experiment reveals that religion amplifies dualistic tendencies. At the same time, however, the modal response across most countries was the cessation of all states. In addition, explicit afterlife beliefs were more prevalent than implicit afterlife beliefs (i.e., continuity judgments). Overall, these data suggest that intuitive materialism is the cross-cultural norm, with dualism arising from culturally acquired beliefs.

The relation between religiosity and well-being is one of the most researched topics in the psych... more The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N=10,535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported beta = 0.120). For the second research question, this wa...

Scientific Reports

People face stressors that are beyond their control and that maladaptively perpetuate anxiety. In... more People face stressors that are beyond their control and that maladaptively perpetuate anxiety. In these contexts, rituals emerge as a natural coping strategy helping decrease excessive anxiety. However, mechanisms facilitating these purported effects have rarely been studied. We hypothesized that repetitive and rigid ritual sequences help the human cognitive-behavioral system to return to low-entropy states and assuage anxiety. This study reports a pre-registered test of this hypothesis using a Czech student sample (n = 268). Participants were exposed to an anxiety induction and then randomly assigned to perform one of three actions: ritualized, control, and neutral (no-activity). We assessed the effects of this manipulation on cognitive and physiological anxiety, finding that ritualized action positively affected anxiety decrease, but this decrease was only slightly larger than in the other two conditions. Nevertheless, the between-condition differences in the reduction of physiolo...

Proceedings of the National Academy of Sciences

To address claims of human exceptionalism, we determine where humans fit within the greater mamma... more To address claims of human exceptionalism, we determine where humans fit within the greater mammalian distribution of reproductive inequality. We show that humans exhibit lower reproductive skew (i.e., inequality in the number of surviving offspring) among males and smaller sex differences in reproductive skew than most other mammals, while nevertheless falling within the mammalian range. Additionally, female reproductive skew is higher in polygynous human populations than in polygynous nonhumans mammals on average. This patterning of skew can be attributed in part to the prevalence of monogamy in humans compared to the predominance of polygyny in nonhuman mammals, to the limited degree of polygyny in the human societies that practice it, and to the importance of unequally held rival resources to women’s fitness. The muted reproductive inequality observed in humans appears to be linked to several unusual characteristics of our species—including high levels of cooperation among males...

Evolutionary Human Sciences, 2023

Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punit... more Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punitive and monitoring gods that care about moral norms facilitate cooperation. While there is some evidence to suggest that belief in supernatural punishment and monitoring generally induce cooperative behaviour, the effect of a deity's explicitly postulated moral concerns on cooperation remains unclear. Here, we report a pre-registered set of analyses to assess whether perceiving a locally relevant deity as moralistic predicts cooperative play in two permutations of two economic games using data from up to 15 diverse field sites. Across games, results suggest that gods' moral concerns do not play a direct, cross-culturally reliable role in motivating cooperative behaviour. The study contributes substantially to the current literature by testing a central hypothesis in the evolutionary and cognitive science of religion with a large and culturally diverse dataset using behavioural and ethnographically rich methods.

Scientific Data, 2016

A considerable body of research cross-culturally examines the evolution of religious traditions, ... more A considerable body of research cross-culturally examines the evolution of religious traditions, beliefs and behaviors. The bulk of this research, however, draws from coded qualitative ethnographies rather than from standardized methods specifically designed to measure religious beliefs and behaviors. Psychological data sets that examine religious thought and behavior in controlled conditions tend to be disproportionately sampled from student populations. Some cross-national databases employ standardized methods at the individual level, but are primarily focused on fully market integrated, state-level societies. The Evolution of Religion and Morality Project sought to generate a data set that systematically probed individual level measures sampling across a wider range of human populations. The set includes data from behavioral economic experiments and detailed surveys of demographics, religious beliefs and practices, material security, and intergroup perceptions. This paper describ...

Frontiers in Psychology, 2013

Collective rituals are biologically ancient and culturally pervasive, yet few studies have quanti... more Collective rituals are biologically ancient and culturally pervasive, yet few studies have quantified their effects on participants. We assessed two plausible models from qualitative anthropology: ritual empathy predicts affective convergence among all ritual participants irrespective of ritual role; rite-of-passage predicts emotional differences, specifically that ritual initiates will express relatively negative valence when compared with non-initiates. To evaluate model predictions, images of participants in a Spanish fire-walking ritual were extracted from video footage and assessed by nine Spanish raters for arousal and valence. Consistent with rite-of-passage predictions, we found that arousal jointly increased for all participants but that valence differed by ritual role: fire-walkers exhibited increasingly positive arousal and increasingly negative valence when compared with passengers. This result offers the first quantified evidence for rite of passage dynamics within a highly arousing collective ritual. Methodologically, we show that surprisingly simple and non-invasive data structures (rated video images) may be combined with methods from evolutionary ecology (Bayesian Generalized Linear Mixed Effects models) to clarify poorly understood dimensions of the human condition.

Journal of Cognition and Culture, 2013

Anthropological theories have discussed the efffects of participation in high-arousal rituals in ... more Anthropological theories have discussed the efffects of participation in high-arousal rituals in the formation of autobiographical memory; however, precise measurements for such efffects are lacking. In this study, we examined episodic recall among participants in a highly arousing firewalking ritual. To assess arousal, we used heart rate measurements. To assess the dynamics of episodic memories, we obtained reports immediately after the event and two months later. We evaluated memory accuracy from video footage. Immediately after the event, participants' reports revealed limited recall, low confijidence and high accuracy. Two months later we found more inaccurate memories and higher confijidence. Whereas cognitive theories of ritual have predicted flashbulb memories for highly arousing rituals, we found that memories were strongly suppressed immediately after the event and only later evolved confijidence and detail. Physiological measurements revealed a spectacular discrepancy between actual heart rates and self-reported arousal. This dissociation between subjective reports and objective measurements of arousal is consistent with a cognitive resource depletion model. We argue that expressive suppression may provide a link between individual memories and cultural understandings of high-arousal rituals.

Psychological Science, 2013

PLoS ONE, 2014

Previous research has shown that ideas which violate our expectations, such as schema-inconsisten... more Previous research has shown that ideas which violate our expectations, such as schema-inconsistent concepts, enjoy privileged status in terms of memorability. In our study, memory for concepts that violate cultural (cultural schema-level) expectations (e.g., ''illiterate teacher'', ''wooden bottle'', or ''thorny grass'') versus domain-level (ontological) expectations (e.g., ''speaking cat'', ''jumping maple'', or ''melting teacher'') was examined. Concepts that violate cultural expectations, or counter-schematic, were remembered to a greater extent compared with concepts that violate ontological expectations and with intuitive concepts (e.g., ''galloping pony'', ''drying orchid'', or ''convertible car''), in both immediate recall, and delayed recognition tests. Importantly, concepts related to agents showed a memory advantage over concepts not pertaining to agents, but this was true only for expectation-violating concepts. Our results imply that intuitive, everyday concepts are equally attractive and memorable regardless of the presence or absence of agents. However, concepts that violate our expectations (cultural-schema or domain-level) are more memorable when pertaining to agents (humans and animals) than to non-agents (plants or objects/artifacts). We conclude that due to their evolutionary salience, cultural ideas which combine expectancy violations and the involvement of an agent are especially memorable and thus have an enhanced probability of being successfully propagated.

How do people feel during extreme collective rituals? Despite longstanding speculation, few studi... more How do people feel during extreme collective rituals? Despite longstanding speculation, few studies have attempted to quantify ritual experiences. Using a novel pre/post design, we quantified physiological fluctuations (heart rates) and selfreported affective states from a collective fire-walking ritual in a Mauritian Hindu community. Specifically, we compared changes in levels of happiness, fatigue, and heart rate reactivity among high-ordeal participants (fire-walkers), low-ordeal participants (non-fire-walking participants with familial bonds to fire-walkers) and spectators (unrelated/unknown to the fire-walkers). We observed that fire-walkers experienced the highest increase in heart rate and reported greater happiness post-ritual compared to low-ordeal participants and spectators. Low-ordeal participants reported increased fatigue after the ritual compared to both fire-walkers and spectators, suggesting empathetic identification effects. Thus, witnessing the ritualistic suffering of loved ones may be more exhausting than experiencing suffering oneself. The findings demonstrate that the level of ritual involvement is important for shaping affective responses to collective rituals. Enduring a ritual ordeal is associated with greater happiness, whereas observing a loved-one endure a ritual ordeal is associated with greater fatigue post-ritual.

Religion, Brain & Behavior, 2013

We explore the cognitive effects of three common features of religious interactions: (1) demand f... more We explore the cognitive effects of three common features of religious interactions: (1) demand for the expressive suppression of emotion; (2) exposure to goaldemoted and causally opaque actions; and (3) the presence of a charismatic authority. Using a cognitive resource model of executive function, we argue that these three features affect the executive system in ways that limit the capacity for individual processing of religious events. We frame our analysis in the context of a general assumption that collective rituals facilitate the transmission of cultural ideas. Building on recent experiments, we suggest that these three features increase participants' susceptibility to authoritative narratives and interpretations by preventing individuals from constructing their own accounts of the ritual event.

TEDxAthens 2016 From fire-walking to meditation, and from graduation ceremonies to wine toasting,... more TEDxAthens 2016
From fire-walking to meditation, and from graduation ceremonies to wine toasting, rituals are everywhere. But what purpose do they serve?

The program is based on experiential learning. Students have the opportunity to conduct their own... more The program is based on experiential learning. Students have the opportunity to conduct their own projects and participate in faculty-led research. Following a problem-focused approach, instruction moves beyond traditional disciplinary lines, drawing from a wide variety of qualitative and quantitative methods. The program is also immersive. In contrast to most other study abroad programs, it does not consist in taking classes at another university. Instead, lessons are held in a variety of locations related to the course material, from local temples and restaurants to public beaches and UNESCO World Heritage monuments. Students will have the opportunity to interact with the local community, participate in their rituals, meals, and other activities, and get a first-hand experience of the Mauritian way of life. This program takes place in a truly unique setting. Mauritius is one of the most diverse societies in the world, where members of numerous ethnic, religious, and linguistic groups live and interact in close proximity. Due to its fascinating history and human geography, it makes an ideal natural laboratory for the social sciences.