She isn't sure about who she is anymore and here we are sitting and asking questions and forcing her to small-talk. And she keeps asking us

who are you

how do you know me

why are you here

have I met you before?

Over and over.

But she isn't interested in answers.

Hers is a better class of nursing home so I'd hate to see the ones for poor people. You get used to the urine smell, and the floors are all so shiny that it is easily cleaned up. But that smell of food, and the dribbles, is what drives me out.

May is immaculate, I might add, and not just for family pride. She grooms herself well every day and insists on help from the staff when she can't do it. At her ninety fifth birthday party at my mother's house, she looked like a sweet little doll in her best dress, brooch, scarf. Colourful and crisp.

The remembering. The stoppages. She stops herself. That rhythm. In this implausible setting I think of, hear going around in my head, the music of the minimalists. Robert Ashley's ordinary chatter, incessant, in his opera-for-television Improvement (Don leaves Linda).

Behind her bed, hanging on the wall, are framed photographs of sons and grandchildren. These are the only mementos she has carried with her into this final home.When she sits up in bed, as she does for large periods of each day, she looks upon another treasure taken from her former life. It is a glorious portrait of Ingrid Bergman as Joan of Arc: victorious, proud, a perfect Hollywood image from the past.It towers over us. When I ask her who that lady is, she is unsure - mother, sister, daughter. No, she didn't have a daughter.I am sure she wanted to tell me it was May.

The shifting nature of memory, the treasures taken through a life. The family home now sold and its contents disposed of. And this big photograph: a woman burned at the stake. Before the ignominy of this, though; on her horse, in her armour. Beautiful and purposeful.

She is at the end of the line of family, this old, old woman. She is the grandaughter of Brina and Theodore Krakouer. Her final home is the Masonic Nursing Home in a suburb of Perth; she lived her adult life in Collie and Perth. Now she is in this institution which I visit with my mother, her favourite niece. A research visit. The ordinary grotesque: the old men pushing themselves around narrow corridors for exercise and entertainment. I suppose for some to stop is to die. Things growing on their faces, a general decay of bodies and minds. Their memory going, they live quite in the present. I am trying not to make judgements.

When we first arrive, we collide with a tandem team, a husband and wife both in wheelchairs, moving about and arguing, still, in the way you could imagine they have for their life together. My mother helps out by pushing a chair when asked by the woman, and the man is deeply offended. Brooding, dark, emasculated.

May, Aunty May, in a room of her own. You can see the wilful streak still in her face. She has always been a cheeky woman, a stirrer, defiant. I've never been sure what she has been defiant about. She has dementia, Alzheimer's. Looks you straight in the face and repeats every question you ask her. Throws it right back.

To interrogate an octogenarian with dementia about her childhood and her family: I must be stupid. I have come, earnestly, with the tools to stimulating memory: photographs and stock phrases, names and relationships. Between answering her questions of who we both are, which come every couple of minutes, there is lucidity. I have a photograph of her as a little girl, five years old, with her parents, some siblings. We ask her about her childhood: trying to tap into those images and memories of far away that may hold more significance than the place she is trapped in right now, this delusional space where she can't hold a thing, not even the last question answered. She identifies everybody in the photographs: Mother, Grandmother Patterson, Father, Grandfather, herself, her sister Fay and brothers Raphael and Abraham, a cousin. I ask her about them - what was your mother like, your father, were you happy?

She tells me, directly, the only direct thing she has to say to me, that it is too late, that she has now forgotten all of that, all of the detail. I have come too late. And that's that. I, of course, try to trick her because I want my visit to yield up something. I want it to be worth my while.

- Do you dream about your Mum and Dad?

- Yes, I do. I still do.

- I want to write a story about our family.

- Oh why? They were very ordinary. Nothing more than that. My mother was kind and good. My father was blind. Yes, he was good too, a kind and gentle man, even after he went blind.

It is too late. There is no such thing as a family receptacle, a place where knowledge is stored. I have to do all of this bloody work myself. Fossicking work and, ultimately, patchwork. Following my own interests and building a family retrospectively. I have to do this, so it's my selection of material.

In other narratives of Perth there are tales of a blind violin player in a small country town, who once needed to travel to Perth to perform his violin on street corners to collect a few morsels to keep on living. In other words, to beg.

The truth is that he was dead at the beginning of the Depression, in 1930, at the age of 61 years. He married at the age of 29.On the death certificate, his father Theodore is named as a storekeeper.I requested the death certificate and read the column 'Cause of Death'.Tabes Dorsalis. Uraemia. Heart failure. I understood the second two ailments, but the primary cause of death was confusing. All I could think of was sharks swimming in the ocean, circling around a target.