(AP) — Autism scientists are seeking more brain samples for research.

They announced Thursday a new network collecting brain specimens around the country. They say the more they get, the better the chances of finding better ways to treat the developmental disorder.

So far the network has four sites: Mount Sinai medical school in New York, the University of California in Davis, the University of Texas Southwestern in Dallas, and McLean Hospital near Boston.

A freezer malfunction damaged many of that Harvard-affiliated hospital’s specimens. Neuroscientist Robert Ring of the advocacy group Autism Speaks says the network was planned before that.

Ring says the network has more than 6,000 people signed up to be donors after death. Brains from people with autism and without are needed.