Politically extreme individuals exhibit similar neural processing despite ideological differences

Although liberals and conservatives are often assumed to differ in how they think about politics, growing evidence suggests that what most distinguishes politically extreme individuals from moderates is not the content of their beliefs but the affective intensity with which those beliefs are processed. In a recent functional MRI study, de Bruin and FeldmanHall (2025) scanned US participants while they viewed naturalistic political videos and found that those reporting more extreme ideological positions—on either the left or the right—showed heightened responses in affect-related regions, including the amygdala and anterior insula, as well as greater between-subject neural synchrony with other extreme partisans, regardless of side. Because such convergent neural responses across opposing camps suggest a shared affective mode of engagement, the authors argue that ideological extremity is best understood as an emotionally driven style of political cognition, rather than a difference in factual reasoning. This pattern in turn implies that interventions aimed at reducing polarisation should likely target affective rather than purely informational processes. These conclusions, however, must be qualified: the design is correlational, the sample is restricted to US participants, and ideology was self-reported, so the findings may not generalise to multiparty systems or to non-electoral forms of extremism.