How to make the earth move with a wooden board and two simple notes

Michael Church didn't think 'monochord' therapy would work. Then he climbed on...

'Get up on that and lie down." What, on a bare wooden board like a mortuary slab? Well, I've no particular ailment, but I'll try anything which promises, without drugs, to do me good. Underneath the board is a barrel-shaped belly along which 50 metal strings are stretched, and with the aid of these Sonia Slany proposes to work a spell.

'Get up on that and lie down." What, on a bare wooden board like a mortuary slab? Well, I've no particular ailment, but I'll try anything which promises, without drugs, to do me good. Underneath the board is a barrel-shaped belly along which 50 metal strings are stretched, and with the aid of these Sonia Slany proposes to work a spell.

The board is uncomfortable, and I'm aware of strenuous work on the strings below. I concentrate, and wonder what on earth I'll find to say about this transparent piece of hokum. No images come to my mind, no out-of-body ecstasy. It's banal, a con. Better get up, apologise for wasting her time, and go home.

Then something odd happens: I wake up. Not fully, but enough to realise I've been in a trance from which I now have no desire to emerge. I've been hypnotised before, and recognise the symptoms: the wooden board is now quite comfortable. I still see no images, but I lie there luxuriating in an interesting sensation: as though I were floating over water, cocooned in sound. And the sound, which initially seemed risible, has become a miasma of melodies and cross-rhythms. One simple instrument producing just two notes, but in reality more like a symphony orchestra. It feels infinitely relaxing, and I'm sorry when it finally dies away.

Did the earth move? Yes, but why should it have done so? This young woman's answer is part-biographical, part-musicological, and partly medical in a way I only dimly understand. Sonia Slany is a concert violinist who tours with Ryuichi Sakamoto, a jazzer with her own band, and a music-therapist with this strange instrument which goes by the misleading name of "monochord". It was the need to heal her own inner conflicts which propelled her into music-healing: she likes to use the monochord in tandem with a therapist using massage or acupuncture. She talks a lot about "chakras" and "meridians", about the body releasing its toxins.

The power of the monochord, with 25 strings tuned to one note and 25 to the fifth above, lies in the overtones it generates: it shares this capacity with the gong, the didgeridoo, the Alpine horn, and the Tibetan temple bowl. As a jazz instrument (she and her group are playing this week in the London Jazz Festival) it makes a wonderfully effective drone. But as a therapeutic tool, its career has only just begun. There are only four others in Britain.

On the other hand, Pythagoras and Hildegard of Bingen were on to the principle underlying it: the idea goes right back, as does the concept of music as a healing agent. Theophrastus, in the third century BC, noted the flute as a cure for sciatica; the Romans believed it could cure snake-bite. Current research linking music, mood-swings, and brain function suggests that such beliefs may not have been entirely far-fetched. In Awakenings, Oliver Sacks records the amazing therapeutic power which music has for patients with neurological disease.

Whatever music actually is - and philosophers are forever trying to penetrate the mystery - it's transmitted by means which are unmysteriously physical. So it should come as no surprise that its effects are also physical, and that animals respond to it, too. Think of birds and hump-backed whales, of snake-charming, and of the custom - observed by Thomas Hardy - whereby farmers sang to their cows to get a better yield of milk.

Good vibes are more than a figure of speech.

Sonia Slany's 'Monochord Music' (Village Life, 2CDs), is available from 020 8360 4975; £16. She performs at London Jazz Festival, Purcell Room, SE1 (020 7960 4242), 17 Nov