In my experiments I’ve found that the most rigid thinkers have genetic dispositions related to how dopamine is distributed in their brains.
Rigid thinkers tend to have lower levels of dopamine in their prefrontal cortex and higher levels of dopamine in their striatum, a key midbrain structure in our reward system that controls our rapid instincts. So our psychological vulnerabilities to rigid ideologies may be grounded in biological differences.
In fact, we find that people with different ideologies have differences in the physical structure and function of their brains. This is especially pronounced in brain networks responsible for reward, emotion processing, and monitoring when we make errors.
For instance, the size of our amygdala — the almond-shaped structure that governs the processing of emotions, especially negatively tinged emotions such as fear, anger, disgust, danger and threat — is linked to whether we hold more conservative ideologies that justify traditions and the status quo.
Thinking patterns are reinforced physically, makes sense.
Outside of topical debates, the key difference between conservatism and progressivism is risk taking vs risk avoidance.