Key points from article :
In 2008 archaeologists discovered a human brain dating to the Iron Age.
Brain so-called "Heslington brain" was found in the village of Heslington.
An unknown disease may alter the person's brain proteins before he or she expired.
Scientists think that an acidic fluid invaded the brain and prevented enzymes from causing decay.
Heslington brain was an anomaly, with more filaments in the outer, gray matter areas.
Treatments of diseases that involve protein aggregates need a more long-term approach than previously thought.
