In the 19th century, men in clubs would sit in their leather chairs with scotch and pipes, and speculate on the source of the Nile. There was no information so there was no shortage of theories. A mountain range larger than the Himalayas, enormous underground springs, primordial caves. Today, the PCC occupies the same role in the brain sciences. Neuroscientists sit around in labs and at conferences and make wild guesses, fumbling around in the dark. Your guess is just as good as ours.
We sometimes act like the brain is fully mapped out, and there is nothing new to see, but there are large swathes where we haven't even gotten past step one.
