A psychiatrist says a phenomenon called earthquake brain is affecting the ability of some people in the Christchurch to think clearly.
Caroline Bell said it comes from a build-up of the stress hormone cortisol.
Ms Bell said people are now less worried about actual earthquakes and more concerned about how the disaster has affected their day-to-day lives.
She warned the worst could be yet to come for those suffering quake-related anxiety, depression and stress.
The third year after a natural disaster is often considered the worst if outstanding matters such as insurance payouts are still unresolved.