Which condition is considered progressive rather than reversible?

A chronic or persistent disorder of the mental processes caused by brain disease or injury and marked by memory disorders, personality changes, and impaired reasoning is considered progressive and irreversible, an acutely disturbed state of mind characterized by restlessness, illusions, and incoherence, occurring in intoxication, fever, and other disorders and coma have the potential for reversal, and depression and anxiety are reversible

Not only is it the purchase of about 40% of america, it also grounds to on-go our advancement as a civilization.