Brain scans of happy people help explain their ‘rose-tinted’ outlook

The brains of people with a happy disposition seem to respond more strongly to positive things in their environment

Female orgasm captured in series of brain scans

The animation will help scientists understand how the female brain conducts the symphony of activity that leads to an orgasm

Mirror therapy may help to reduce the pain of arthritis

An optical illusion involving a mirror can trick the brain into reassessing a hand with arthritis as healthy and pain-free

UK’s oesophageal cancer rate is worst in Europe

Cancer charity attributes Britain's poor global placing – equal with Rwanda – to high alcohol intake and growing obesity

Heavy drinking in pregnancy can alter unborn babies’ brains, study shows

People born to alcoholic mothers at risk of problems ranging from poor brain development to loss of hearing and vision

Multiple gene test allows more targeted treatment of cancer

SNaPshot test looks for mutations in key genes of patients with cancer so they can be given the most effective drugs

Resveratrol pills may mimic effects of exercise and low-calorie diet

A small study suggests the grape extract resveratrol has similar metabolic effects to exercise and calorie restriction

Yoga may work better for lower back pain than conventional treatments

Patients with lower back pain who did yoga showed bigger improvements in their ability to perform everyday physical tasks

The world is home to 7 billion people, but how far have we come?

Babatunde Osotimehin: The population milestone is a reminder that there is much work to do on sexual and reproductive health and HIV if we are to meet the millennium development goals by 2015

Zanzibar’s Islamic scholars tackle sex, contraception, and HIV and Aids

Damian Carrington: Religious leaders are behind a shift in attitudes that could reduce HIV infection, improve maternal health and curb population growth