Eating ice cream really does make you happy. Scientists have found that a spoonful of the cold stuff lights up the same pleasure centre in the brain as winning money or listening to your favourite music.

Neuroscientists at the Institute of Psychiatry in London scanned the brains of people eating vanilla ice cream. They found an immediate effect on parts of the brain known to activate when people enjoy themselves; these include the orbitofrontal cortex, the "processing" area at the front of the brain.

The research was carried out by Unilever, using ice cream made by Walls, which it owns. Don Darling of Unilever said: "This is the first time that we've been able to show that ice cream makes you happy. Just one spoonful lights up the happy zones of the brain in clinical trials."

The scientists used a functional magnetic resonance imaging machine to watch blood flowing to activated brain areas when people swallowed ice cream.

Developed to investigate the effects of brain damage and disease, the scanners are being increasingly turned to non-medical uses.

Experts are gathering in Cardiff today to discuss how magnetic resonance imaging could investigate how the brain handles situations including disappointment and loneliness.

Peter Halligan, professor of neuropsychology at the university, is leading the establishment of a £12m centre, opening in January, which will investigate the emerging field of social neuroscience.

He said the centre would use the imaging machine to study brain activity when lies are told, and when people fake illness.

He has already used scans to show activity in regions associated with deception, distinguishing between people hypnotised into being unable to move a leg and others pretending not to be able to do so.