Even as the NFL continues to make rule changes in an attempt to protect its players from concussions, the concussions still happen—and they happen often.

With the help of @NFLConcussions, which monitors media and league injury reports throughout the season, we've compiled the available video of the concussions in the NFL in the first half of the season. The list is below, but it's by no means complete—some of the concussions, especially from the preseason, are based off of media reports and not the league's official Injury Report. If you've got any additions, please let us know.

2011 NFL Concussions

Preseason: David Vobora (then with Rams), Michael Hoomanawanui (Rams), Ben Watson (Browns), Mike Johnson (Falcons), Eugene Sims (Rams), Lawrence Guy (Packers), Art Hicks (Redskins), Edgar Jones (Redskins), Ramon Foster (Steelers), Jason Campbell (Raiders), Jahvid Best (Lions), Evan Moore (Browns), David Bruton (Broncos), C.J. Wilson (Packers), John Parker Wilson (Falcons), Joe McKnight (Jets), Derrick Ward (Texans), Cheta Ozougwu (Texans), Rashad Jennings (Jaguars), Zackary Bowman (Bears), Clint Session (Jaguars), Anthony Levine (Packers), Malcolm Floyd (Chargers), Donald Jones (Bills), Deji Karim (Jaguars), Jeremy Mincey (Jaguars), Tony Fiammetta (then with Panthers), Chris DeGeare (Vikings), Jason Phillips (Ravens), Marcus Gilbert (Steelers), Rich Ohrnberger (Patriots), Terrence Toliver (Texans), Evan Royster (Redskins)

Week 1: Mike Wright (Patriots), Jeff Otah (Panthers), Harry Douglas (Falcons)

Week 2: Michael Vick (Eagles)*, Terrence Cody (Ravens)*, Charles Godfrey (Panthers)*, Mario Manning (Giants)*, Kyle Arrington (Patriots)*, Alex Smith (49ers)

Week 3: Kerry Collins (Colts)*, Geno Hayes (Bucs)*, Michael Huff (Raiders)*, Riley Cooper (Eagles)*, David Thomas (Saints)*, Chris Gamble (Panthers), Jason Snelling (Falcons), Justin Durant (Lions), Ricky Brown (Raiders)

Week 4: Gerald Sensabaugh (Cowboys)*, Mike Williams (Seahawks)*, Tom Zbikowski (Ravens), Jeremy Shockey (Panthers), Garrett McIntyre (Jets)

Week 5: Tony Scheffler (Lions)*, Christopher Owens (Falcons)*, Zach Miller (Seahawks)*, Mike Tolbert (Chargers)*, Drew Coleman (Jaguars), Donald Strickland (Jets), Daryl Smith (Jaguars), Chris Snee (Giants), Matt Giordano (Raiders), Zak DeOssie (Giants), Darren Colledge (Cardinals), Jahvid Best (Lions)

Week 6: Troy Polamalu (Steelers)*, Sam Shields (Packers)*, Jamarca Sanford (Vikings)*, Jordan Pugh (Panthers)*, Thomas Williams (Panthers)*, AJ Edds (Colts), Scott Fujita (Browns), Ryan Pickett (Packers, in practice)

Week 7: Mohamed Massaquoi (Browns)*, Kevin Boss (Raiders)*, Jason Smith (Rams)*, Darrell Scott (Rams)*, Kris Dielman (Chargers)*, Ben Watson (Browns), Jacob Tamme (Colts)

Week 8: Husain Abdullah (Vikings), Quinton Carter (Broncos)

*Included in video.

2010 Concussions: The Year In NFL Concussions (So Far): A Horrifying Video Compilation