metacognition

 A thought is not simply “watched” by another hidden observer in the brain. Metacognition is the brain’s ability to represent and evaluate its own mental processes.

It involves networks across the prefrontal cortex, anterior cingulate cortex, and frontoparietal regions that monitor information such as confidence, errors, attention, and the accuracy of our own decisions. When you recognize “I’m thinking about my thinking,” the brain is generating a higher-order representation of its own cognitive state.

In a sense, the brain becomes both the thinker and the subject being examined.