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Scientists have been able to virtually transport a man back in time - simply by stimulating parts of his brain.

A 22-year-old man reported seeing scenes from his family's pizzeria as well as his local train station, all while sitting in a medical room.

Researchers hope the discovery could help them better understand areas of the brain used to retrieve information on locations.

Dr Mégevand at the Feinstein Institute in New York first scanned the volunteer's brain using functional MRI while he looked at images of different objects and scenes. Activity from the implanted electrodes was then recorded as the patient looked at a similar set of pictures

The halluciations appeared after Pierre Mégevand at the Feinstein Institute in New York implanted electrodes into the young man's brain in search of the origin of his epilepsy.

This involved drilling tiny holes in the skull through which doctors inserted 2 inch-long (5cm) electrodes and guided them to specific points in the brain tissue.

Dr Mégevand first scanned the volunteer's brain using functional MRI while he looked at images of different objects and scenes, according to a report by Helen Thomson in New Scientist.

Activity from the implanted electrodes was then recorded as he looked at a similar set of pictures.

The halluciations appeared after Pierre Mégevand implanted electrodes into the young man's brain in search of the origin of his epilepsy. This involved drilling tiny holes in the skull through which doctors inserted 2 inch-long (5cm) electrodes and guided them to specific points in the brain tissue

The team found that an area of the cortex around the hippocampus was activated when the subject looked at images of places.

'There are these little spots of tissues that seem to care about houses and places more than any other class of object,' team member Ashesh Mehta at the Feinstein Institute told the New Scientist.

The implanted electrodes were used to stimulate the brain in this area which triggered a series of visual hallucinations.

The young man initially described seeing a familiar railway station and later a part of his home, but no smells or sounds were associated with the scenes.

When stimulation of these brain areas was repeated, the same hallucinations occurred.

And when the researchers stimulated electrodes in a slightly different area, in the inferior temporal gyrus (ITG), the volunteer said that faces suddenly became distorted.

'Maybe a specific group of neurons encodes a memory of a person wearing an apron, another group encodes an oven or a street, and when you stimulate them altogether it evokes a familiar memory of that place where all those things were,' said Dr Mehta.

Dr Mehta said the experiments may eventually help people who who suffer from conditions such as autism or Alzheimer's disease.

The research follows a study at Stanford University, which two years ago revealed that electrodes placed another area in the brain were vital in a person's ability to process faces.

When the researchers stimulated electrodes in a slightly different area, in the inferior temporal gyrus (ITG) shown here in yellow, the volunteer said that the doctor's faces suddenly became distorted