Concussions have been in the news lately especially as it relates to football; however, cyclists are susceptible to concussions. Concussions are a form of Traumatic Brain Injury (TBI). This article provides some resources on concussions and brain trauma. It is not meant to serve as the final word on the topic. If you suspect that you have suffered a concussion, please seek medical attention; if you think a friend, teammate, child, partner or just the guy down the street might have suffered a concussion, please encourage (or drag them if it is your kid) to the doc for evaluation.
Bernard Condevaux, PT gave a presentation on concussions at the USA Cycling Coaching Summit in October 2010. He was kind enough to repeat the presentation as a webinar. A recording of the webinar is available along with the handouts.
In addition to the webinar, a group of physicians created a document for coaches and team managers that covers many of the same issues in the above webinar.
National Federation of High Schools also provides a free informational webinar.
ImPACT (TM) has a lot of resources as well.