Lover's touch is special

A passionate touch generates specialised sensations

Scientists say they have proved that the touch of a loved one is indeed special.

They have found that tender caresses stimulate a different part of the nervous system than that activated by the everyday sensation of touch.

Researchers have long suspected that that specialised nerves are involved in transmitting information to the brain when the skin is being touched in a passionate or sensitive way.

This is because these type of touches generate such a different response.

However, it has proved very difficult to stand up this theory because the sense of touch is highly complex and triggers a multitude of nervous responses.

Scientists have finally been able to prove the existence of an "emotional touch" system by carrying out tests on a 54-year-old Swedish woman who has no normal sense of touch.

Illness

An illness at the age of 31 left the woman's main touch nerves - a variety known as large myelinated afferent fibres - unable to function properly.

In lab tests when a probe was drawn across the woman's skin she was unable to tell in which direction it was moving.

However, the women still retained full use of a type of touch fibres known as CT afferents.

When her arm was stroked lightly with a soft paintbrush, mimicking the tender touch of a lover, she could feel a slight, but pleasant sensation.

Next the researchers carried out a brain scan which revealed that the CT nerves stimulated parts of the brian known to process emotions.

The researchers, from Sahlgrenska University Hospital in Sweden, believe this shows that it is the CT nerves that are stimulated by a tender caress.

Lead researcher Dr Håkan Olausson told BBC News Online: "We have discovered a new sensory system in man that transmits information about touch with a slow speed to the brain.

"This slow touch system does not signal what we mean by touch in daily life.

"Instead it signals the pleasant aspects that can be evoked by touch stimulation."

Dr Olausson said the slow touch system had first been identified 10 years, but its function was not previously known.

The research is published in the journal Nature Neuroscience.