Finding #3: People rationalize their happiness.

Reasons: Studies indicate we hate to regret our decisions, and regret inaction more than poor actions. We are good at rationalizing reasons for the latter to make ourselves feel better. Conversely, we don't like having good things that happen to us explained, as we like the freedom to indulge in all sorts of rationalizations for how we caused some sort of good luck.

Application: While the lesson here seems similar to the last one, exceeding player expectations is slightly more interesting. When I played Mass Effect and chose an "evil" response in a conversation, I was happily surprised when my character didn't just spit out a canned angry line, but threw the poor alien against a wall and held a gun to its head. I felt like I had cleverly chosen a line that perfectly matched my alignment.

Be careful not to abuse this phenomenon. Too much surprise becomes confusion. Most feedback should still be a direct acknowledgment of player skill or dedication, or just as a reaction to input. Designers already know that.

However, when the situation is right, give them positive feedback that allows an open interpretation, such that they can ruminate on whatever vainglorious achievement they did that was responsible. Pick a random player stat like number of bunnies slain, slap it on an [insert weapon] of Bunny-slaying, and give it to the player. They will brag to everyone about what they think they did to deserve it.

Finding #4: People tend to experience loss twice intensely as gain.

Reason: Scientists believe we are biologically primed to have greater loss aversion than a desire for gains. Why do we hold on to losing stocks, telling ourselves it's not a loss until you sell it? There are innumerable theories as to why we have evolved this way, but so strong is this factor that we also tend to expect greater rewards for delayed gratification. Would you rather have $50 now, or $60 next year (forget inflation for a moment)?

Application: Ameliorate and justify punishments. Similar to the presentism finding, people tend to remember their recent experiences more strongly, and that affects their happiness more. Filmmakers discovered that whether or not someone liked the last scene of a film is highly influential in how much they liked the whole film in retrospect. Similarly, the hype surrounding a film quickly causes a so-so movie to become a terrible one when it fails to match expectations.

Two games that handle the design taboo of frequent deaths well are Super Smash Bros. and Resident Evil, where dying is almost as much fun as succeeding because the player is primed for it. In the first, the player becomes part of the hilarious chaos onscreen, and in the second, it fits the survival theme.

It is worse to set-up an exciting situation and not resolve it satisfyingly than to have never set it up in the first place. Imagine being told you won the lottery, but then it turned out it was a mistake! You get an apologetic $100 only to find out the winner was your neighbor. You had a net gain, but you aren't going to be very happy since "losing" the lottery is you present state.

Another tactic to reduce pain is to do what casinos do and surround loss with pleasure. See -- there is a use for pleasure! They surround players with a rewarding environment (comps, drinks, sounds, showgirls, etc.) that acts to positively reinforce financial loss. That's why modern digital slot machines emit clinking sounds despite how gamblers swipe a credit card through now.

Big gory deaths in your typical FPS stimulate the nucleus accumbens, the part of our brain that gives us dopamine-powered orgasms, and it also happens to be activated by the anticipation of pleasure. Stimulating it can prime players into accepting more risk.

Failure in WarioWare is just as fun as winning, more so when you make a fool out of yourself doing it.