Primary sources
John Crace rounds-up research news from around the globe, this week: the chimpanzees that have developed their own tool kits
Why women have sex
According to a new book, there are 237 reasons why women have sex. And most of them have little to do with romance or pleasure
Working in a team increases human pain threshold
Working as a group thought to boost the rush of endorphins, a feel-good chemical released in brain that helps dampen down feelings of pain
Brain scans can identify the most sociable people
People who value the company of others most have denser grey matter in two brain areas
My virtual support network
Most people with depression need some kind of therapy, but could a computer replace a counsellor? Tim Lott finds out
The truth about lying
Psychologist Paul Ekman tells Jon Henley how 'microexpressions' betray us when we tell a lie
Make me a superhero: The pleasures and pitfalls of body enhancement
We should welcome with open arms the rich possibilities of technologically enhancing our bodies, says Andy Miah. Just so long as we don't all end up looking, thinking and acting the same
A nation running scared
Ed Halliwell: When 77% of Britons say the world has become a more frightening place, it's time to look at how emotions rule our lives
Expand your mind
Further psychology resources: events and seminars, online discussion forums and psychometric tests