It's common to read about the damaging effects of video games, quite often without any supporting evidence whatsoever (hello Baroness Greenfield!). It was refreshing therefore to hear Dr Jane McGonigal at SXSW yesterday talking about the positive effects of gaming.

McGonigal is a game designer, researcher and author and her talk at SXSW was based on her book, Reality is Broken: Why Games Make Us Better and How They Can Change the World. For me it was the highlight of the conference so far; McGonigal is an inspiring and engaging speaker and what she had to say was fascinating.

The central thrust of her talk was that play is essential to our psychological wellbeing. Humans love to play games and McGonigal quoted philosopher Bernard Suits, who describes games as "unnecessary obstacles we volunteer to tackle".

Before you become enraged at the prospect that video games might actually be a good thing and not a blight upon civilisation, I should point out that this applies to any game. McGonigal gave golf as an example: the object is to get the ball into the hole but the most sensible way to do that is to pick it up and put it in, not to attempt to lob it in from hundreds of yards away by hitting it with a stick.

We set these unnecessary obstacles for ourselves because overcoming them is fun. It creates a positive kind of stress, called eustress, which is actually good for us. It gives us a sense of achievement, makes us more ambitious and more likely to succeed.

Here are some of the positive effects of gaming that researchers have uncovered:

• Children who play cooperative games for just 25 minutes per week are more likely to cooperate with and help others in real life
• Almost three quarters of people who own a musical instrument report spending more time playing it after playing a music video game
• Just 90 seconds of playing a video game with an avatar that you consider 'sexy' will boost your confidence for the rest of the day
• Research by the US Army has found that three to four hours of video gaming per day reduces the effects of post-traumatic stress disorder. Perhaps surprisingly, more violent video games are more effective
• Gamers have fewer nightmares than non-gamers and are more likely to have lucid dreams that they can control

McGonigal acknowledged that there is a limit. Positive effects of gaming are seen in those who spend anything up to 21 hours per week playing video games. Between 21 and 28 hours per week has less positive effects and anything over 28 hours can tip you into addiction and can have negative effects. That said, watching 28 hours of television per week is probably not that good for you either.

Unlike many of gamings critics (hello Baroness Greenfield!), McGonigal offered sources for these claims and you can read more about them in her book. I certainly intend to.