Answer and Explanation:
Through many media sources, it is seen that people can "override" the human reflex action.
The way those people are able to be seemingly unaffected by actions and objects that would normally make others flinch or react is by training themselves to be unaffected. They may still feel pain but won't instantly react to the pain.
For example, everyone will feel pain to a boiling hot mug of tea. For many, when they touch the mug, they will pull their hand/finger away due to the intense heat the mug has. For those who trained to not reflex, they may be able to hold on longer than most others to the mug of tea. Even so, they may still pull away from the mug as it is hurting their hand.
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