If one were to ask you which is worse: intentionally destroying someone’s artwork or playing Monopoly incorrectly, what would you say?
The first act is a violation of a “moral norm,” a norm that preserves the rights of others. The second act is a violation of a “conventional norm,” a norm that serves to ensure coordination within social groups or institutions.
New research at the University of Virginia has, for the first time, found evidence that children as young as 3 show physiological changes (dilation of the eyes’ pupils) that co-occur with the distinction these toddlers draw between violations of moral and conventional norms.
“It won’t come as a surprise to anybody if I were to tell you that some rules are much more important than others,” said Meltem Yucel, the lead author of the study, published in the April 17 issue of the journal Frontiers in Psychology.
“We know that we shouldn’t be hitting people, and [that] hitting people is worse than breaking a game rule. And even young children are able to make this distinction at a very early age, around the age of 3,” she said.
Yucel, a developmental psychology Ph.D. candidate who conducts research in UVA’s Early Social Development Lab, said her team wanted to better understand how humans distinguish between different types of rules and what makes people perceive one rule to be more important than another.
In the new study, 3- and 4-year-olds, as well as UVA undergraduate students, were observed as they watched two videos: one video of people tearing up another’s artwork and the other video of people violating game rules.
That’s where the eyes come in. In some ways, eyes are indeed the windows to the soul; when humans have their emotions roused, their pupils get wider.
“We looked at how much their pupil size changed,” Yucel said. “Could we be more physiologically aroused or excited for some norm violations more than others? Maybe we are more aroused after we see a moral violation. And, that is indeed what we found.”
Yucel also looked at how children and adults paid attention to the videos. She found that even though people looked at these videos for the same duration, they paid attention to different aspects of it. Children and adults looked more to the victim of the moral violation than the bystander in the conventional transgression.
The study, which involved 66 preschoolers and 64 undergraduate students, began in 2016 and builds on the work of Yucel’s academic adviser, associate professor of psychology Amrisha Vaish. In prior research, Vaish has shown that 3-year-old children enforce moral norms on others and 5-year-old children recognize and value individuals who sanction others for breaking moral norms.
So why are Yucel’s new findings important?
“So far, we have always assumed that moral and non-moral rules are somehow different,” she said. “But we have never really shown how this comes about and whether or not emotions or affect is involved in this distinction.
“In this study, we show that even at the very earliest age where children are able to distinguish between norms, they can also show an affective arousal difference.”
As a recognition of the significance of this work, Yucel received the 2020 Association for Psychological Science/Psi Chi’s international Albert Bandura Graduate Research Award for the most outstanding graduate research paper.
The new findings, she said, are important because now researchers can look at even younger children to see “if this arousal difference is there … are 2-year-olds doing this too?” she asked.
Yucel said it’s difficult to do these types of studies with children younger than 3, “but perhaps by using these types of physiological measures, we can start asking when children begin to draw differences between the moral and conventional lines,” she said.
Human group living and cooperation rely heavily on social norms that regulate how one ought to behave (Boyd and Richerson, 2009; Killen and Smetana, 2015). These norms are often enforced by adults—and even young children—to ensure fair treatment of others and harmonious group living by protesting, punishing, or tattling on norm violators (Rakoczy et al., 2008; Balafoutas and Nikiforakis, 2012; Gummerum and Chu, 2014; Riedl et al., 2015; Yucel and Vaish, 2018).
However, not all norms are treated equally. Adults and even young children distinguish between moral norms, which are aimed at preserving the rights and welfare of others (e.g., not causing unprovoked harm or not stealing from others), and conventional norms, which serve to ensure coordination within social groups or institutions (e.g., playing a game correctly or wearing uniforms to school). By 3 years of age, children judge moral norm violations as more serious, moral transgressors as more deserving of punishment, and moral norms as more generalizable across contexts and less contingent on authority (see Smetana et al., 2018, for a review).
This distinction is also evident in children’s behaviors. For instance, 3-year-olds protest when a puppet attempts to opt out of moral rules but not conventional rules (Josephs and Rakoczy, 2016), and enforce moral rules on both in- and out-group members but enforce conventional rules selectively on in-group members only (Schmidt et al., 2012; see also Liberman et al., 2018). Children thus distinguish moral from conventional norms remarkably early in development (Smetana, 1981; Smetana, 2013; Ball et al., 2017; Turiel and Dahl, 2019).
Although research has extensively documented that children verbally differentiate between moral and conventional norms, less is known about whether affect underlies these early domain distinctions. Most prior work in this area has focused on whether young children recognize the criteria that are believed to form the basis of these distinctions.
In this “social domain” perspective, children’s criterion judgments about norm transgressions and their justifications for their judgments are used to demonstrate that children have moral concepts and recognize distinctive features of morality (see Smetana et al., 2014; Ball et al., 2017). Moral norms function to prevent harm and promote welfare and justice, and thus, children recognize that in contrast to conventional norms, moral norms are obligatory, generalizable, and unalterable. Importantly, these criterion judgments and justifications are fundamentally cognitive in nature: They reflect children’s reasoning and conceptualization of the social world.
There is, however, a growing recognition of the role of emotions and arousal in children’s and adults’ domain distinctions. Social domain theorists propose that children’s own emotional responses and their observation of others’ emotional responses to norm transgressions contribute to the development of their domain distinctions (Turiel and Killen, 2010).
For example, children develop a concept of a moral norm against harming others by coming to appreciate which actions cause others harm, an understanding that emerges by empathizing with those who are harmed as well as experiencing the pain of being harmed oneself (Wainryb et al., 2005; Ball et al., 2017). Caregivers also respond differently to moral versus non-moral transgressions.
For instance, parents physically intervene more, give more harm-based reasons, and focus more on the victims of harm when enforcing moral norms compared to conventional norms (Dahl and Campos, 2013), and mothers use more angry vocalizations in response to moral transgressions than non-moral transgressions (Dahl et al., 2014).
In turn, infants associate firm vocalizations more with moral transgressions than other types of transgressions (Dahl and Tran, 2016). Domain theorists argue that these distinct social interactions and experiences help children construct an understanding of social domains such that by around 3 years of age, they reliably differentiate the different domains.
Emotivists propose a more primary role for the emotions in the moral–conventional distinction. Haidt (2001) prominently proposed that people’s moral judgments are based primarily on affective intuitions and that conscious deliberation primarily serves to produce post hoc rationalizations for the intuitive, emotional reactions that occur first. Nichols (2002, 2004) further emphasized the role of affect in the distinctions we make between moral and conventional norms.
Specifically, he argued that people (including young children) have a “Normative Theory,” or a nascent understanding of what is acceptable and what is prohibited. When this “Normative Theory” detects a norm violation, and this violation is affectively charged, it is perceived to be a moral norm violation, whereas when the violation is not backed by affect, it is considered non-moral.
Indeed, Nichols (2002) showed that if conventional norms become coupled with affect (e.g., disgust), adults no longer perceive them as conventional norms and instead perceive them as belonging to the moral realm, and thus judge them as less permissible, more serious, and more contingent on authority than affect-neutral conventional violations. This effect is also evident in development: by the age of 7 years, children moralize novel rule violations and judge them as more wrong when those rules are backed by affect-laden testimonies (Rottman and Kelemen, 2012; Rottman et al., 2017).
These findings offer partial support to Nichols’s account that affect is central to and forms the basis of adults’ and children’s domain distinctions.
Despite the disagreement across theories on the role they prescribe to affect, the aforementioned approaches all agree that affect is involved in the moral/conventional distinction. For example, observational research examining naturalistic responses to transgressions shows that young children respond more emotionally to moral transgressions than conventional or personal transgressions (Nucci and Turiel, 1978; Smetana, 1984, 1989; Nucci and Weber, 1995; Killen and Smetana, 1999).
Although 3-year-olds (and in some cases, even 2-year-olds) seem to react more emotionally to moral transgressions, these prior studies were not experimental and thus did not permit causal conclusions. Furthermore, these studies assessed children’s emotional expressions, which may underestimate sensitivity to transgressions in younger children who may experience internal arousal that is not displayed overtly.
Surprisingly, no experimental work to date has shown whether affect is involved when children first begin to make the distinction between moral and conventional norms around 3 years of age. It thus remains unknown whether affect in fact underlies the psychological distinction young children draw between moral and non-moral norms, as both social domain theorists and emotivists propose.
Absent evidence for this claim, we must consider the alternative possibility that affect only enters the picture later in development, that is, it is layered on top of moral judgments that initially emerge as a result of more deliberate processes. Moreover, establishing the role of affect in early development is a foundational step toward understanding how it is involved.
In particular, it holds promise for addressing the tension in the literature about whether affective responses to norm transgressions result from or give rise to children’s domain distinctions. Our goal in the present study was to take this foundational step.
Notably, one recent study did broach this issue in the context of children’s direct involvement (Hardecker et al., 2016). This study revealed that 5-year-old but not 3-year-old children showed more overt agitation (such as anger, annoyance, or yelling at the transgressor) to moral than to conventional transgressions.
Although this hints that affect may not be involved when children first begin to distinguish moral from conventional transgressions at age 3—challenging findings from prior observational studies—it is also possible (as the authors acknowledge) that the task was too demanding for this younger group.
For instance, perhaps 3-year-olds in this study did experience greater internal arousal to moral than conventional transgressions, but this did not manifest itself in their overt behaviors. A more sensitive measure of internal arousal could provide evidence of distinct affective responses to moral versus conventional transgressions even at this young age.
In the present study, therefore, we asked whether moral transgressions elicit different levels of internal arousal at the age when children first begin to make the moral–conventional distinction (3 years) or only after children have had some experience making the moral–conventional distinction on more conceptual grounds (4 years). Furthermore, we asked whether any differences in internal arousal that children show are comparable to those shown by adults in order to chart the developmental trajectory of the affective responses to norm transgressions.
In contrast to previous work, which relied on children’s behavioral or verbal measures of affect (Arsenio and Ford, 1985; Hardecker et al., 2016), we assessed children’s and adults’ internal affective arousal via changes in their pupil dilation. Human pupils dilate in response to affectively charged images and audio stimuli (Partala and Surakka, 2003; Bradley et al., 2008; Henderson et al., 2014).
Greater internal arousal corresponds to increased pupil dilation, which can be measured via slower (tonic) changes and more immediate (phasic) changes (Sirois and Brisson, 2014; Hepach and Westermann, 2016). Children’s tonic pupil dilation increases in response to harm-like situations such as seeing others needing help and children anticipating the correct solution to resolve the situation (Hepach et al., 2016; Hepach and Herrmann, 2019).
An important advantage of pupillometry is that, unlike behavioral or verbal measures, which are often limited in terms of the ages with which they can be used, pupil dilation can be measured and interpreted similarly across ages (Hepach and Westermann, 2016; Krüger et al., 2019).
Past studies on moral development that have relied on behavioral or verbal measures have often included either young children or adults but have not compared young children’s responses to those of adults (Arsenio and Ford, 1985; Nichols, 2002; Rottman and Kelemen, 2012; Hardecker et al., 2016; Rottman et al., 2017; though see Decety et al., 2012).
Our use of pupillometry, on the other hand, allows us to examine internal arousal to norm transgressions across age groups. Specifically, we assessed both tonic and phasic changes in participants’ pupil dilation in response to moral and conventional transgressions.
This allowed us to investigate (1) shifts in children’s arousal state (tonic changes in pupil dilation) as well as (2) time-locked immediate changes in pupil dilation in response to viewing key events in the situations presented to children (phasic changes).
The present study addressed two further questions regarding children’s responses to norm transgressions. The first was whether children and adults pay attention to different aspects of a moral versus a conventional norm violation. Prototypical moral transgressions generally involve victims (because they involve harm or injustice), and so they affect other people, whereas conventional transgressions do not directly harm other people (Turiel, 1983; Smetana, 1985). In fact, prior work indicates that children and adults look more at the victims (people or objects) that are the target of harmful actions than they look at the perpetrators (Decety et al., 2012, p. 216).
We thus hypothesized that victims of moral transgressions should elicit greater attention than bystanders who are present during (but not harmed by) conventional transgressions (see also Vaish et al., 2009). This differential looking would also importantly demonstrate that, in line with prior work, participants did discriminate between the two types of transgressions. We thus used gaze tracking to measure participants’ looking to the victim in the moral transgression as compared to looking to the bystander in the conventional transgression.
Looking time has been long used with infants and children to measure their attention allocation to social stimuli (Aslin, 2007; Gredebäck et al., 2009; Decety et al., 2012). We further assessed whether this differential attention correlates with differences in internal arousal, either because those who focus more on the victim may thereby become more affectively involved in the transgression or, alternatively, those who are more affectively involved in a transgression may attend more to the victim.
A more exploratory question concerned participants’ resource allocation toward the transgressors versus the victim/bystander. Both adults and children show concern and prosocial behavior toward victims of moral transgressions (Vaish et al., 2009; Vaish et al., 2011a; Decety et al., 2012; Leliveld et al., 2012) and punish moral transgressors, such as by taking resources away from them or allocating fewer resources to them (Fehr and Fischbacher, 2004; Leliveld et al., 2012; Reich and Hershcovis, 2015; Smetana et al., 2018).
Smetana et al. (2018) found that children allocated fewer resources to moral than conventional transgressors. Moreover, in interview studies, children judge moral transgressions as more punishable than conventional transgressions (Smetana, 1981).
It is thus possible that children and adults also allocate more resources to the victim of a moral transgression than the bystander in a conventional transgression, and fewer resources to a moral than a conventional transgressor. To explore these possibilities, we ended the study with a resource allocation task wherein participants could distribute three resources between the transgressor and victim/bystander.
Finally, based on a recent study showing a positive association between changes in children’s arousal (measured via tonic changes in pupil dilation) and their motivation to help (Hepach et al., 2018), we assessed whether participants’ pupil dilation correlated with their resource allocations.
Though we did not have strong predictions, we considered that participants (i) may feel more concern for and thus allocate more resources to a victim than a bystander and (ii) may judge moral transgressions more negatively and thus allocate fewer resources to a moral transgressor than a conventional transgressor.
Further, participants who showed greater arousal (pupil dilation) to a transgression may have greater prosocial motivation and thus allocate more resources to the victim/bystander. With these experimental and exploratory goals, we aimed to shed light on the affective, attentional, and behavioral aspects of the moral–conventional distinction in early development.
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Source: University of Virginia