JOAN Brosnan-Walsh is telling a sweet and funny story about the young actor who played her grandson on the RTE soap Fair City. As you would expect from an actress, she gesticulates gracefully and uses her eyes expressively throughout the three or four minute tale. But at times it can still be a little difficult to catch everything she says.

'People tell me my speech hasn't got any worse over the last six months,' she says. 'But I think myself it has because I have to make a greater effort and the muscles get tired. After doing the Late Late Show I was exhausted. But getting the feedback afterwards, people did understand what I was saying.'

It was while she was on holidays with her next door neighbour in October 2007 that Joan first began to slur her words. 'It was as if I was drunk and we were kidding that I had too much the night before,' she explains. 'But it didn't go away.'

It took almost eight months for the actress to be finally diagnosed with Motor Neuron Disease, (MND) a degenerative condition that destroys the cells that control voluntary muscles and can affect speaking, walking, breathing, swallowing and general movement.

But in the meantime she had to cope with continuing to work as her ability to talk was steadily and mysteriously deteriorating. Given her high-profile role as Mags Kelly in Fair City, a part she played for twenty years before retiring just before Christmas, it was, to put it mildly, a somewhat embarrassing not to mention very public episode.

'I was mortified,' she says with impressive candour. 'So they wrote in that I was having dental problems. At one stage they had my grandson say: "Granddad, what's wrong with granny's voice?" And Charlie (her on-screen husband played by Tom Jordan) replied: "She's having trouble with her teeth."

'I had to change some of the words in my script because there were certain words I couldn't say, people were looking at me and wondering what was wrong with me. I heard a rumour that they thought I was inebriated on the set.'

Joan laughs out loud at the memory of her confused co-stars. Dressed casually in blue jeans and a deep-purple top with a scarf knotted elegantly around her neck, she still looks far younger than the seventy years she happily admits to being. 'Well, I stick on a lot of slap,' she smiles. 'And before this, I guess I was very healthy and fit for my age. Also I've lost a bit of weight, they (the doctors) don't like you to do that but swallowing becomes difficult, you literally get tired of chewing and swallowing so you start eating less but I have to watch that. There's also probably some muscle wastage.'

Perched on the sofa in the comfortable sitting room of her home in Malahide, north Dublin, she is chatty and open about her condition. Approximately one in 50,000 Irish people develop MND each year and around 250 people are being treated at any one time. Life expectancy for sufferers varies from three to five years (or occasionally longer) after onset, depending on the activity of the disease and the particular muscle groups affected.

Last year the association raised over E1.5million, only one third of this amount was awarded by the state. The funds are used for research, to find causes and cure, and also to improve the quality of life for the person with MND so that they may retain independence and live at home.

'I want to try and help raise the profile of MND,' Joan explains. 'When they told me I had it, I knew absolutely nothing about it. I knew Stephen Hawkings had it and I think David Niven had it too, but apart from that - nothing. Imagine, I spent my adult life worrying about cancer and Alzheimer's and then suddenly this appeared out of the blue.'

Picturing the gnarled and twisted body of the theoretical physicist Stephen Hawkings in his wheelchair cannot have been easy for Joan.

'Well, I think you can only take in only so much at a time,' she says. 'I thought of him all right, but it's kind of unreal. I knew what was going to happen but I think your mind closes down to try and protect you, I accepted that I was ill and wasn't going to get better.'

Born in Greystones, Co Wicklow, Joan met her husband Willie when they were both working for Aer Lingus. They celebrated their golden wedding anniversary last October and have three daughters, Helen, 46, Ingrid, 43 and Ruth 41 and four grandchildren. Ruth is expecting their fifth grandchild in just a couple of weeks.

Joan studied drama at the Brendan Smith Academy but as her children were born she gave up the classes and joined a local amateur group instead. 'I hated being at home with babies, so every evening when Willie came home from work the kids were in bed by seven and I was gone,' she explains. 'As the kids got older I started trying to get into the professional theatre. I was forty when I started to act full-time, I always wanted to do it but in the 50s we were a working class family and back then you got a good pensionable job, there was none of that singing and dancing nonsense.'

She was fifty when she got the role of Mags Kelly in Fair City, a job she enjoyed for twenty years. But two years ago, things started getting harder for Joan.

'I remember feeling tired and I wonder now was it this (the MND) starting,' she says. 'I suddenly thought: "I'm sick of this commute." I always loved the job but I was thinking I was getting too old, I cut back my weeks in Fair City back to ten weeks a year. And I wanted to go on these two holidays we had always promised ourselves, to China and the Canadian Rockies. Maybe on subconscious level I knew something was wrong, we never got to China or Canada.'

It was nine months ago that Joan finally found out what was wrong with her.

'Willie was with me when the doc told me, I was very calm. They tell you it's degenerative and there isn't a cure. But they also tell you that everyone is different. You could live two years, you could live twenty. But I was very calm, in fact for the first few weeks I felt a sense of relief. You see I'm a worrier, I'm a cheerful kind of person on the outside but I worry. I'd spent all my life worrying but suddenly here was something presented to me so I could stop worrying.

Just three weeks after she was diagnosed she bumped into an acquaintance at a friend's party.

'I only half knew her really and we started talking, she was asking about Fair City and I told her I was giving it up because of my speech. She asked me why and I told her I had MND. "So have I," she said. There was absolutely nothing wrong with her speech, so I saw how everyone who suffers with MND is different. She only had a leg brace and maybe a bit more discomfort. She'd had it for eight years and she'd written a history book, she gave me such hope.'

Joan is still able to get around quite well with the help of a very sophisticated looking walker and a chair lift gets her up the stairs of her home to where she has a little studio.

'I've always painted but now my right hand is going and I can't hold a blooming brush so I've started doing abstracts with my left hand in chalk and squeezing the acrylic paint onto the canvas. They're silly really but I enjoy it,' she smiles. 'I think because I'm an actress it was particularly tough the way it affected my speech but the worst thing is my singing voice I sang all my life. I did musicals and was in the local choir, it's a wonderful way to get rid of tension. But now I can't sing a note and I miss it so much.'

Yet despite what she has lost and the uncertainty of what lies ahead, Joan is remarkably up-beat and there is not a hint of self-pity.

'I have down days,' she insists. 'And with this condition your emotions are more to the fore. I don't remember crying much before, once of twice when I had real cause to. But I never cried much, I always laughed a lot, now I find I cry easier. But with the muscles in my face I can't even cry comfortably, I'm like a Banshee. But after a few minutes it's over. Most of the time I'm good.

'I don't let myself think too much and if I'm awake at night, which is always the worst time to think about anything, I read. I've never thought it was unfair, I've been angry but angry at nothing in particular, little things like if I can't put on my shoe.

'I fluctuate between thinking maybe it would be better if I went quicker rather than slower because then it wouldn't be long and drawn out with me ending up in a wheelchair helpless. But then I think life is still so interesting. But honestly, I don't get too depressed about it, and my family and friends are marvellous, they're all lined up to bring me to the movies and the art galleries, places I always want to go. And I can still drive my car, it's automatic.

'Besides people are making it wonderfully easy for me. Willie is fantastic, all my friends are hovering waiting to help. Orla Hardiman at Beaumont Hospital is a wonderful woman and her whole team are exceptional. And there's the local occupational therapist, Roisin Nolan, she's with the HSE and I never had a good word for the HSE but I'm changing my tune. I only have to lift the phone and tell Roisin what I need, like a grab rail in the bathroom, within a week it'll be there. I have a new scooter in the garage that I haven't had a chance to take out yet. That will give me great freedom, I'll be able to go down to the sea.'

Yet for all her positiveness, Joan is only too aware of the seriousness of MND.

'I know I can't be cured and that's all I really know but I'm seventy. I heard of a young man of 32 who was diagnosed and yesterday I heard of a man of fifty, that's tragic.

'I don't seem to be too afraid,' she says with a small smile. 'I'm not scared yet.'

* For further information about MND you can log on to www.imnda.ie or contact the Irish Motor Neurone Disease Association at 1800 403 403.