Substance use disorders, commonly called drug addictions, are defined by persistent use of a substance impairment resulting from the substance (Diagnostic and Statistical Manual of Mental Disorders, 2022). Drug addictions are present in about 5% of the US adult population (Sussman et al., 2011). While addiction symptomatology can vary, addiction is typically characterized by risk-taking behaviour and cravings (Diagnostic and Statistical Manual of Mental Disorders, 2022). Symptoms differ based on the specific substance. For example, psychotic or bipolar disorder symptoms may be associated with stimulants like amphetamines but not opioid or caffeine addictions (Diagnostic and Statistical Manual of Mental Disorders, 2022). Despite differences in symptomatology, it appears as though most drug addictions are related to the same brain system dysfunction (Koob et al., 1998).
While researchers have struggled to isolate genes responsible for addiction (Volkow & Muenke, 2012), there is little doubt that addictions have a hereditary component (Li & Burmeister, 2009; Volkow & Muenke, 2012). Twin studies suggest that the genetic risk for addiction is especially relevant in early adulthood (Vrieze et al., 2012).
Despite the increasing amount of research on the biological causes of addiction, individuals with addictions are stigmatized. Individuals with addiction are subject to negative prejudice from their family, friends, coworkers, and even healthcare workers (Earnshaw et al., 2013). Depictions of addiction in the media contribute to this stigma (Cohn et al., 2020; McGinty et al., 2019). In media, addiction is often depicted as affecting individuals who are violent or criminal, reducing sympathy toward individuals with addiction (McGinty et al., 2019). Addiction is also often framed as a choice which increases the perception that addiction is a sign of weak character (McGinty et al., 2019). The insinuation that adduction is a personal failing is often internalized by individuals with addiction (Matthews et al., 2017). Individuals who self-stigmatize feel deep shame about their condition, and may pursue drugs to avoid feelings of shame, exacerbating the addiction (Matthews et al., 2017). Additionally, people who self-stigmatize are less likely to seek treatment (Earnshaw et al., 2013). Taken together, it is clear that addressing addiction stigma is an important part of improving health outcomes for people with addiction.
An open question is how beliefs about the biological bases of addiction contribute to or mitigate addiction stigma. Addiction specialists have argued that knowledge of the biological bases of addiction will increase advocacy for evidence-based medical treatment for addiction (Richter et al., 2019). However, research has not tested how believing in a biological basis to addiction affects stigma. To address this question, we take an essentialist perspective.
Essentialism as a Mechanism for Understanding Addiction Stigma
Essentialism is the perception that category membership is caused by an inherent invisible essence (Gelman, 2003; Medin & Ortony, 1989). This essence grants individuals’ category membership and category-specific features (Medin & Ortony, 1989). For example, when thinking of a “tiger”, it is not the orange-and-black stripes that cause a tiger to be a tiger. Rather, it is an invisible tiger essence that grants category membership, and is also causally responsible for the orange-and-black stripes (Gelman, 2004). Our representations of categories are tied to essences (Medin & Ortony, 1989). People understand both natural kinds (Gelman & Hirschfeld, 1999; Taylor et al., 2009) and social categories (Hirschfeld, 1995; Hussak & Cimpian, 2019; Siddiqui et al., 2020; Siddiqui & Rutherford, 2021) in an essentialist manner.
Essentialism creates the percept that category members are similar to one another (Gelman, 2004) and as such it is often associated with stereotyping and prejudice. Various studies have found that essentialism correlates with stereotype endorsement (Bastian & Haslam, 2006; Keller, 2005). Essentialism is also associated with prejudice in the domains of race (Williams & Eberhardt, 2008), sexual orientation (Haslam et al., 2002), and in minimal groups paradigms (Rhodes et al., 2018). Children shared fewer resources with a novel social outgroup if that outgroup was described in essentialist terms (Rhodes et al., 2018).
Haslam et al. (2000, 2002) divided essentialism into two subfactors: entitavity and natural kindness. Entitavity refers to how coherent categories are. Entitative categories are uniform, informative, and exclusive (Haslam et al., 2000). Natural kindness refers to how biological a category is perceived to be. Natural kind categories are perceived as immutable, natural, and discrete (Haslam et al., 2000). Combined, an essentialist view of categories involves a perception that category membership is fixed at birth, and that category members are inherently similar to one another (Gelman, 2003).
The biological basis subfactor of essentialism is causally implicated in prejudice. In a study by Williams & Eberhardt (2008), participants read one of two news articles that detailed a fake, recent scientific study. In the essentialism condition, they read about a study that found the genetic basis of race. In the anti-essentialism condition, they read about a study that definitively found that there was no genetic basis to race. Participants who read the essentialist article were less willing to interact with Black individuals, and were more willing to accept racial inequities (Williams & Eberhardt, 2008). These findings have been replicated with other paradigms (Andreychik & Gill, 2015) as well as across other social categories (Haslam & Levy, 2006). For example, having a biological view of mental illness is associated with desires for social distance from those with mental health disorders (Haslam, 2011). This set of results suggests that having a biological view of a social group may promote prejudice against that group. However, it is unknown whether this extends to individuals with addiction, especially given that addiction researchers have argued that a biological view of addiction reduces stigma about addiction and its treatment (Richter et al., 2019).
The Current Study
The current study adopts an essentialist framework for understanding how a biological view of addiction affects addiction stigma. Using fictional news articles modified from Williams & Eberhardt (2008), participants either read an article highlighting a genetic explanation for addiction (pro-essentialism), denying a genetic explanation for addiction (anti-essentialism), or a control article. Participants then completed an essentialism scale adapted from Bastian & Haslam (2008) as well as an addiction stigma scale based on items from Kennedy-Hendricks et al. (2017) and Barry et al. (2014). If having a biological view of addiction increases stigma, participants in the pro-essentialism condition will have the highest stigma scores, and participants in the anti-essentialism condition will have the lowest stigma scores. If having a biological view of addiction decreases stigma, participants in the pro-essentialism condition will have the lowest stigma scores, and participants in the anti-essentialism condition will have the highest stigma scores.