Mapping the Social-Norms Literature: An Overview of Reviews

The concept of social norms, commonly understood as the unwritten rules shared by members of the same group or society, is cross-disciplinary. Reflective of that diversity, the theoretical literature on social norms is multifaceted and at times contradictory. In an attempt to give those engaged in cross-disciplinary conversations a common language and understanding, this study provides a map of the social-norms literature by comparing existing reviews and highlighting areas of agreement and disagreement.

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the researchers obtained 22 studies for inclusion in this qualitative synthesis. (Table 1 in the paper provides an overview of these studies as an indication of the discipline from which they originated and the aim to which they were written. They identified 4 theoretical spaces of inquiry that were common across the reviews:

1. What are social norms?
   • Table 2 summarises the areas of implicit and explicit consensus and debate about what social norms are and are not. There are 3 main points of consensus: Most reviews agree that social norms must be "social" in some sense (although they disagree on what this means - see below); most agree that social norms inform action-oriented decision making in some way; and most mention that social norms can affect people's health and well-being (in both positive and negative ways).
   • Six reviews focus on theories that define social norms as individual constructs (psychological states of individuals, such as beliefs or emotions); 10 privilege theories of social norms as collective constructs (external (as opposed to internal) forces affecting people's actions). The researchers find advantages of using norms as individual constructs in public-health research and action as well as in targeted behaviour change interventions in international development. On the other hand, theories that define social norms as collective constructs may be helpful to those investigating how norms operate and diffuse through time at the population level. Integrating the two approaches might be helpful in uncovering their dialectically reciprocal influence.
2. What relationship exists between social norms and behaviour? There is disagreement related to:
   • Whether reviewers consider one or multiple pathways of influence from norm to action - Reviews that consider one normative pathway include, for example, the suggestion that social norm compliance is exclusively motivated by the presence or anticipation of positive or negative sanctions or by the simultaneous presence of both empirical and normative expectations (concepts not too conceptually distant from, respectively, descriptive and injunctive norms). Other reviewers suggest multiple pathways to compliance, recognising that norms can translate into action in a variety of situations and under different conditions. Some look at descriptive and injunctive norms as two pathways of influence.
   • Whether they understand norms as "direct" or "indirect" sources of influence - Norms are direct sources of influence when they alone are sufficient to direct behaviour; by contrast, when a norm is an indirect source of influence, it intersects with one or multiple intermediary factors (e.g., behavioural, individual, and/or contextual) that can either strengthen or reduce the influence of a norm. When a norm exerts indirect influence, changing norms may not be sufficient to change behaviour because the ecology of factors sustaining that behaviour might still hold.
   • The specific pathways that lead from norm to action - Three pathways in particular emerged from the analysis, which the researchers argue are actually intersecting and nonexclusive. According to these pathways, norms affect behaviour by:
     • Providing value-neutral information: indicating practical or efficient courses of action for what the individual had set out to do.
     • Creating external obligations: exerting pressure through role modeling, social pressure, or anticipation of (as opposed to actual) rewards and penalties. Relevant here in the literature is the term pluralistic ignorance, which refers to cases in which most people disagree with a norm but comply with it because they do not know the extent to which others also disapprove of it.
     • Becoming internal obligations: whereby people comply with a norm because of the value they attach to it rather than because they anticipate consequences for complying with it or not.
3. How do social norms evolve? Three stages of a norm's life cycle surface as common themes across the reviews (though reviewers describe the key stages in different ways and break them down into different substages - see Table 4 in the text):
   • Emergence, when a norm comes into being - e.g., on one interpretation, the more regular a behaviour becomes in a population, the more individuals will believe there is a norm, and the more individuals believe that a norm exists, the more they will comply with it. As a result, the behaviour becomes more common in the population.
   • Maintenance, when an established norm continues to influence behaviour and practices over time - there is recognition across reviews that norms persist, although much of the literature does not address the processes and forces sustaining norms.
   • Change and disappearance, when a norm ceases to exist or to exert influence - a tipping point is the specific moment when enough people hold attitudes against the existing norm and are ready to change; norm cascades are the process of norm change after a tipping point has been reached as more and more people start imitating those who are changing their behaviour; and punctuated equilibria is an overall description of the evolution of norms.

   Five key mechanisms are identified that facilitate the movement of a norm across these life stages:

   • Correction of misperceptions - e.g., using interpersonal communication, mass media, informational campaigns, small focus-group interventions, observation of others, or online platforms and video games;
   • Structural changes - ecological, historical, economic;
   • Legal reforms - not always effective in changing the norm;
   • Role models - exert social influence and persuasion through emotions, social attachment, personal connections, institutionally or socially conferred authority, or ease of personal identification; and
   • Power dynamics - requires understanding the ways in which groups and individuals can affect norm dynamics on the basis of the place they occupy in the social hierarchy.

   The researchers suggest that efforts to change social norms should look at how these five together interact and overlap rather than investing time and resources into only one of them.

4. What categories of actors must be considered in the study of social norms? The term reference group refers to the relevant others whose behaviour and (dis)approval matter in sustaining the norm; however, the reviews included several, sometimes conflicting, uses of the term. Three (often overlapping) categories of people are key to understanding how social norms are sustained (see Table 5): (i) norm targets, the people who comply with the norm; (ii) norm drivers, the people who exert influence over the norm's life cycle; and (iii) norm beneficiaries and victims, the people who are affected by the social norm, including when they are neither actors nor influencers.

The researchers suggest two lines of enquiry for future research:

• Map out what specific mechanisms are relevant to particular stages and substages in the life cycle of a norm.
• Investigate the relations and transitions between the normative pathways (providing information, creating external obligations, and becoming internal obligations) - e.g., how and when are norms internalised, how and when do changes in individuals' preferences weaken social norms, and how do people navigate conflicting influences from different normative pathways?

In conclusion, they call for "greater cross-disciplinary work to extend and improve our understanding of the rules that bind us, expanding what may be one of the oldest research trajectories in the history of human thought."