Politicians, medical experts, coaches and sports fans will gather at Sonoma State University on Tuesday for a community symposium on athletic concussions. Congressman Mike Thompson, D-St. Helena, will be among the participants.

More than 3.8 million sports and recreation-related concussions occur in the U.S. each year and the frequency of head injuries increasing. The meeting is from 6:30 to 8 p.m. in The Commons at SSU, 1801 E. Cotati Ave., Rohnert Park.