Life has never been ordinary for 27-year-old Natasza Hickmore. Born 70 per cent deaf, she has lived life in a cocoon, unable to participate fully in her social life or job. But last month she became one of the first people in the country to receive a revolutionary hearing aid and it has changed her life.

"I'd never heard a bird sing properly before," explains Natasza, an IT consultant from Reading. "I could hear some sound but now I can hear the melodies. It might not be what the average 27-year old listens to but for me it's incredible. "I've always used a variety of hearing aid devices which meant I could communicate but my hearing wasn't normal."

Until she was given her new digital hearing aid Natasza, like 2.5 million people in the UK, had been using an analogue system. But analogue can never translate sound the way an ordinary person would hear it. "Noise comes in a selection of frequencies," says audiologist Adam Shulberg, managing director of hearing aid specialists Cubex, which has developed the new system. "When you're deaf you can't hear one of those frequencies and that makes sound hard to identify. Someone who can't hear high-frequency sounds, for example, won't be able to hear many of the consonant letters used in speech. Traditionally, hearing aids artificially pick up the missing frequency, completing the noise pattern we hear. But they can't distinguish between what you want to hear and all the other noise at that frequency."

Natasza says: "The noise level in some pubs would be painful. I couldn't focus on one person speaking as the background noise drowned them out, so I couldn't participate. In the end I gave up going to crowded noisy places."

But then Natasza's specialist suggested she try the new digital system. "Digital hearing aids interpret information in the same way computers do," explains Adam Shulberg. "They look at sound waves to determine which ones are important. For example, if you're walking down a busy road and someone is speaking to you the aid is programmed to prioritise speech over traffic - in the same way the brain does normally." So Natasza can now participate in group conversations.

Mary McFadyen, spokeswoman for the RNID, says: "The analogue system is like wearing glasses with tar on them. Remove the tar and everything becomes clear - that's what digital hearing aids do. Digital technology is the biggest advance for deaf people in years."

The device, worn in each ear, has to be customised to the specific frequencies the person is unable to pick up - with volumes that they can deal with. This process can be very difficult to adjust to. "I felt I was living in a bubble, like everything was dampened down; it was exceptionally frightening," says Natasza of the first couple of weeks. "Before, I felt I was in control of my surroundings. With the first sets of new hearing aids I tried that security left me. I couldn't tell where things were or who was around. But eventually we got the right settings."

Natasza says the aids have changed her life. "Before I could hear but I couldn't listen. Now conversations are totally different as I can appreciate the nuances in words and participate more.

"I'm a team leader for an IT company. Meetings were hard as I'd know there were undercurrents going on, that people were having conversations around a subject, but I couldn't pick up on them. I'd always been a shy child and the deafness made that worse. I was confident inside but didn't feel I could express that in case I misheard something and made a fool of myself - now I know exactly what's going on and I'm coming out of my shell.

"My husband Daniel thinks it's fantastic. We met at university nine years ago and he's developed this huge booming voice to make himself heard. Now we can communicate through more subtle verbal signals - which has added a whole new dimension to our relationship." The NHS is launching 20 pilot centres fitting digital hearing aids. Ask your specialist for details. For more information on the Phonak Claro system that Natasza uses (available privately), contact Cubex on 020 7935 5511. Hers cost £3,800. Royal National Institute for Deaf People, tel: 0808 808 0123; textphone: 0808 808 9000.