Extremism describes the adoption of beliefs or actions that reject the norms, institutions, or values of a broader society, often accompanied by a willingness to use or endorse violence in pursuit of ideological goals. It spans the political spectrum and crosses cultural boundaries, showing up in religious militancy, ethno-nationalist movements, far-left insurrection, and newer online subcultures built around grievance. What makes extremism difficult to pin down is that no single factor explains it. Research over the past two decades points to a convergence of personal psychology, group dynamics, structural inequalities, and digital ecosystems that together push ordinary people toward radical positions and, in some cases, violence.
Why Individuals Radicalize
One of the most influential frameworks in radicalization research is the significance quest theory, which proposes that violent extremism is fundamentally about the desire to matter. According to this model, three components interact to push a person toward violence: a motivational need for personal significance, an ideological narrative that frames violence as a legitimate path to that significance, and a social network that reinforces both the narrative and the commitment to act on it.1Political Psychology. The Psychology of Radicalization and Deradicalization: How Significance Quest Impacts Violent Extremism The theory’s shorthand is “need, narrative, and network,” and it applies across ideological lines, from jihadist fighters to far-right lone actors.2Review of General Psychology. The Making of Violent Extremists
The “need” component is triggered by experiences that threaten a person’s sense of worth. Losing a job, suffering humiliation, feeling culturally displaced, or enduring personal trauma can all create a vacuum that extremist ideologies are designed to fill. The narrative then reframes that personal pain as part of a larger collective struggle, turning an individual wound into a cause worth fighting for. And the network provides the social reinforcement, the sense of belonging and validation, that makes the ideology feel real and the violence feel justified. None of these three elements is sufficient on its own. A person can feel deeply insignificant without ever picking up a weapon; it takes a narrative that channels that feeling toward a target and a community that normalizes violent action.
The Role of Perceived Inequality
Beyond individual psychology, structural conditions set the stage for radicalization at a population level. Researchers have increasingly focused on relative deprivation, the feeling that you or your group is unfairly worse off than others, as a driver of extremist endorsement. This is not about absolute poverty. It is about the perception of unfairness, which is why extremism flourishes in wealthy societies as well as poor ones. Relative deprivation can motivate disadvantaged groups to violently challenge the status quo, but it also motivates privileged groups to violently defend their position when they perceive their status as threatened.3PubMed. Understanding violent extremism in the 21st century: the (re)emerging role of relative deprivation
A series of studies across multiple Western countries found that Western-born Muslims scored higher on predictors of extremist endorsement compared to other populations, and that group-based relative deprivation accounted for the difference.4PubMed. Group-Based Relative Deprivation Explains Endorsement of Extremism Among Western-Born Muslims That finding is worth unpacking carefully: it does not mean that being Muslim predisposes someone to extremism. It means that when members of a minority group consistently perceive that their group faces unjust treatment compared to the majority, that perception fuels sympathy for radical responses. The same mechanism operates in white-identity movements, where a perceived loss of social standing and cultural dominance generates the grievance that extremist narratives exploit. Relative deprivation, in other words, is ideologically agnostic. It is about felt unfairness, and different ideologies compete to be the explanation for that feeling.
How Groups Amplify Commitment
Individual grievance and structural inequality create vulnerability, but groups are where radicalization accelerates. The concept of identity fusion describes a state where a person’s sense of self becomes deeply entangled with a group to the point where any attack on the group feels like a personal attack. Among highly fused individuals, group identity taps directly into personal agency, motivating a willingness to fight and possibly die as a defensive response.5PubMed Central. Exploring the Pathways Between Transformative Group Experiences and Identity Fusion This helps explain why extremist violence so often looks self-sacrificial. From the outside, a suicide attack appears irrational. From the inside, when your personal identity is fused with a group under perceived threat, it can feel like self-defense.
Research conducted in Spanish prisons with jihadist inmates illustrates this process in a specific context. Admiration for radical Islamist groups increased identity fusion with religion, which in turn amplified willingness to engage in costly sacrifices.6Humanities and Social Sciences Communications. Admiration for Islamist groups encourages self-sacrifice through identity fusion The prison environment, with its intense social pressure and limited outside contact, acts as a hothouse for this kind of fusion. But the same dynamic plays out in less confined settings: online communities, tightly knit activist cells, and even extended families in conflict zones can all generate the shared experiences that fuse individual and group identity together.
What Happens in the Brain
Neuroscience research has started to reveal what radicalization looks like at the level of brain activity. An fMRI study of supporters of a radical Islamist group in Barcelona measured brain responses as participants indicated their willingness to fight and die for values they considered sacred versus values they did not. When participants expressed willingness to fight for sacred values, activity dropped in regions of the prefrontal cortex associated with calculating costs and consequences.7PubMed Central. Neuroimaging ‘will to fight’ for sacred values: an empirical case study with supporters of an Al Qaeda associate In plain terms, the brain’s usual brake pedal, the part that weighs whether an action is worth the risk, appeared to disengage when deeply held values were at stake.
But the same study offered a more hopeful finding. When participants saw that their peers rated sacred values differently than they did, the cost-calculating region reactivated, especially among participants who were sensitive to social influence. This suggests that “devoted actors” motivated by sacred values are not entirely beyond reach. Peer disagreement, delivered in the right context, may be able to reintroduce the kind of flexible thinking that sacred commitment tends to shut down. The study is small, and it examined only one population, so it would be reckless to generalize too broadly. Still, it offers a neurological window into something practitioners working with radicalized individuals have observed for years: social connections that challenge extremist norms can be powerful tools for pulling people back.
The Biology of Us Versus Them
Extremism depends on a sharp division between in-group and out-group, and some of the biological machinery for that division is older than ideology itself. Oxytocin, the hormone commonly associated with bonding and trust, turns out to play a more complicated role than its popular image suggests. Experimental research has shown that oxytocin promotes in-group favoritism and, to a lesser extent, out-group derogation, creating intergroup bias rather than universal warmth.8PubMed Central. Oxytocin promotes human ethnocentrism A related study found that oxytocin drives what researchers called a “tend and defend” pattern: it boosted trust and cooperation within a group while increasing defensive aggression toward competing groups.9PubMed. The neuropeptide oxytocin regulates parochial altruism in intergroup conflict among humans
This does not mean oxytocin causes extremism. But it does mean that the neurochemistry of human bonding comes with a built-in dark side. The same feelings of warmth and loyalty that bind people to their families and communities can, in the wrong context, intensify hostility toward outsiders. Extremist groups are extraordinarily good at exploiting this. They create conditions of intense in-group bonding through shared rituals, shared suffering, shared identity, and then direct the resulting defensiveness outward toward a dehumanized enemy. Understanding this dual nature of social bonding chemistry doesn’t excuse extremist violence, but it does help explain why tribal loyalty can shade into something much more dangerous so easily.
Online Radicalization and Radical Content
The internet has not invented extremism, but it has changed the landscape of recruitment and radicalization in ways that are still being measured. A systematic review that pooled findings across multiple studies found that passive and active exposure to radical content online showed small but meaningful associations with both cognitive radicalization (adopting extremist beliefs) and behavioral radicalization (taking extremist actions). Passive exposure to radical content online showed a correlation of roughly 0.24 with cognitive radicalization, and active engagement with such content showed a similar-sized relationship of about 0.22.10Campbell Systematic Reviews. What are the effects of different elements of media on radicalization outcomes? A systematic review For behavioral radicalization, the numbers were comparable: around 0.23 for passive and 0.28 for active exposure. Traditional media like television, by contrast, showed essentially no relationship.
These are not large effect sizes in isolation, but they matter at scale. When hundreds of millions of people scroll through platforms where radical content circulates, even a modest increase in radicalization risk across the population translates to thousands of individuals pushed further along a path they might not have traveled otherwise. The distinction between passive and active exposure also matters. Simply encountering extremist content in a feed is associated with roughly the same level of risk as actively seeking it out, which challenges the assumption that only people who are already radicalized go looking for this material.
The same review noted that experimental evidence for mere exposure to media theorized to increase cognitive radicalization showed only a very small effect overall, but a somewhat larger effect among people already high in trait aggression.11Campbell Systematic Reviews. What are the effects of different elements of media on radicalization outcomes? A systematic review So online radical content doesn’t radicalize everyone who sees it. But among people who already carry certain vulnerabilities, the effect is real and measurable. This pattern fits the broader picture of radicalization as a convergence of factors rather than a single cause.
How Language Primes Violence
The pathway from holding extreme beliefs to committing extreme acts is not automatic, and language plays a critical role in bridging that gap. Research on far-right social media has found that dehumanizing rhetoric, language that strips the humanity from targeted groups by comparing them to animals, insects, or diseases, both legitimizes political violence and stirs negative emotions that increase motivation for violent action.12New Media & Society. Dynamics of violent and dehumanizing rhetoric in far-right social media This is not a phenomenon unique to any one ideology. Dehumanization has preceded mass violence throughout history, from genocides to lynchings. What digital platforms have done is speed up the cycle. In earlier eras, dehumanizing propaganda required printing presses and broadcast towers. Today it requires a social media account and a few minutes.
The mechanism is psychological as much as rhetorical. When an out-group is consistently described in subhuman terms, the moral barriers to harming its members erode. People who would never endorse killing a fellow human being can be led to endorse killing a “cockroach” or a “virus,” because those categories don’t trigger the same moral inhibitions. Extremist movements across the spectrum understand this intuitively, which is why so much of their communication effort goes into constructing dehumanizing vocabularies for their targets before any call to action is issued.
Misogyny as Extremism
One of the newer and less widely recognized forms of extremism is rooted in misogyny. A scoping review of the research found that misogynistic extremism is most frequently studied in the context of involuntary celibate (“incel”) subcultures, male supremacism, and its overlap with far-right movements and black pill ideology.13PubMed. Misogynistic Extremism: A Scoping Review Several mass-casualty attacks in the past decade have been carried out by perpetrators who explicitly cited incel ideology, and security agencies in multiple countries have begun classifying certain forms of misogynistic violence as ideologically motivated extremism.
What makes this category tricky is that misogynistic attitudes are far more widespread than misogynistic violence. The line between holding sexist views and endorsing violence is the same line that separates any prejudice from any extremism: it’s the adoption of a narrative that frames violence as justified and a community that normalizes acting on it. Incel forums, for instance, function much like other extremist networks in the significance quest model. They offer a narrative that explains members’ pain (rejection by women), a target to blame (women and “normies”), and a community that validates escalating hostility. The ideology differs from jihadism or ethno-nationalism in content, but the radicalization pathway looks remarkably similar.
Environmental Stress and Conflict
Extremism is typically discussed as a product of psychology and ideology, but environmental conditions are increasingly recognized as accelerants. Research on sub-Saharan Africa found that drought led to roughly an eight percent decrease in expected economic activity at the district level, and that affected districts could then expect about 29 percent more extremist attacks compared to the average district.14World Development Perspectives. Arid fields where conflict grows: How drought drives extremist violence in Sub-Saharan Africa The mechanism is not mysterious: when livelihoods collapse, governance weakens, and competition for scarce resources intensifies, the conditions that produce relative deprivation and group grievance multiply. Extremist organizations step into the vacuum, offering resources, protection, and a sense of purpose to people who have lost all three.
As climate change increases the frequency and severity of drought in vulnerable regions, this link between environmental stress and extremist violence is likely to grow stronger. It also means that seemingly unrelated policy domains, agricultural development, water management, disaster relief, have counterterrorism implications whether or not policymakers think of them that way. Addressing the conditions that make people vulnerable to recruitment may ultimately do more to reduce extremism than targeting the organizations that recruit them.
What Works in Prevention
Given the complexity of radicalization, prevention efforts have to operate on multiple levels. One promising approach borrows from public health: psychological inoculation. The idea is to expose people to weakened versions of extremist persuasion techniques so they can recognize and resist them when encountered in the wild. A study testing a game called Radicalise, which walks players through the manipulative tactics extremist recruiters use, found that playing the game significantly improved participants’ ability and confidence in spotting manipulative messages and the characteristics associated with vulnerability.15Behavioural Public Policy. Active inoculation boosts attitudinal resistance against extremist persuasion techniques: a novel approach towards the prevention of violent extremism
Inoculation works because it gives people a framework for recognizing what is being done to them before they are emotionally invested in the message. Most extremist recruitment does not begin with explicit calls to violence. It begins with content that validates grievances, builds trust, and gradually introduces more radical framings. By the time overtly violent rhetoric appears, the target has already been primed to accept it. Teaching people to see the pattern early, before emotional investment sets in, disrupts the process at its most vulnerable point.
Other approaches target the structural and social conditions that feed radicalization. Community-level programs that address social isolation, provide mentoring for at-risk youth, and create channels for nonviolent political expression have shown promise in multiple contexts. Deradicalization programs that work with individuals already committed to extremist ideologies tend to focus on the network component of the significance quest model: building new social connections that provide meaning and belonging without the ideology. None of these approaches is a silver bullet. The evidence base is still developing, and programs that work in one cultural context may not transfer easily to another. But the research increasingly points in the direction of early, broad-based prevention rather than narrow, reactive security measures as the more effective long-term strategy.
When Extremism Hides in Plain Sight
One of the most persistent misconceptions about extremism is that it looks like what we see in the news: masked fighters, manifestos, mass-casualty attacks. In reality, most extremism operates well below that threshold. It lives in the gradual normalization of dehumanizing language in political discourse, in the quiet acceptance of conspiracy theories that blame identifiable groups for society’s problems, and in the slow erosion of the belief that political disagreements can be resolved without force. By the time violence occurs, a long process of radicalization has already taken place, much of it invisible to outsiders and sometimes invisible even to the person undergoing it.
This is why researchers increasingly focus on cognitive radicalization, the adoption of extremist beliefs, as distinct from behavioral radicalization, the move to violent action. Most people who hold extreme views never commit violence, but the population of people who hold extreme views is the pool from which violent actors are drawn. The size of that pool, and the speed at which people move through it, depends on the social and informational environments they inhabit. A society saturated in dehumanizing rhetoric, sharp in-group and out-group divisions, widespread feelings of relative deprivation, and easy access to radicalizing content online is a society that will produce more extremists, even if the vast majority of its citizens never intend harm. Understanding that broader ecosystem, rather than focusing only on the individuals who cross the line into violence, is where the most productive thinking about extremism is happening today.