The digital gauge on the long, waist-high freezer reads an astonishing -75C. Standing before it, University of Auckland medical school technical officer Jocelyn Bullock pulls two sets of gloves on to each of her tiny hands, the first set grey thermal, the second yellow latex.

She lifts the fridge lid, hauling out a long metal holder resembling a compact disc rack, its shelves holding square cardboard boxes.

Opening a box, she picks out a tinfoil-wrapped lump no bigger than her palm, unpeels a lettered adhesive label and carefully removes two layers of foil.


There, covering half her palm, lies a hard, egg-shaped slice of brain less than a centimetre thick. It's mostly beige with a darker core and frilled edges, bearing coral-like patterns of folds and fissures and threads of red blood vessels. This, she says, is a cross-section of the globus pallidus, involved with processing movement control. There is one on each side of the brain, both deeply buried in its centre.

The slice of tissue forms one piece of a collective 400 brains stored in New Zealand's only brain bank, a crucial tool in the fight against degenerative diseases such as Huntington's, Alzheimer's, Parkinson's and epilepsy.

The bank, now 12 years old, is spread across three lockable, alarmed freezers in the Grafton medical school, two in a small laboratory, the other squatting in a nearby hallway.

The plain surroundings belie the value of the bank to researchers all over the world - and to those who live with brain disease. In a filing cabinet in Ms Bullock's meticulously ordered office sit the permissions of about 100 people who want their brains to go to science when they die.

Among them are Pukekohe's Margaret Horne, 63, and her 51-year-old brother, Doug, who suffers from Huntington's.

Mrs Horne, who does not carry the faulty gene that causes the illness, says she was motivated to donate by her appreciation of the work brain researchers do.

"I decided I wanted to help, and Doug did too. This research will be too late for Doug, but if it can help in some other way, it's really important."

Although she has the word "donor" on her driver's licence, Mrs Horne wanted her wishes to be clear, having seen the "sadness" in her family when her grandmother's wish to donate her eyes after death was discovered only at her will reading.

From the moment a donor dies, the bank has only 24 hours to get a brain treated and stored. Each is split into hemispheres. One half is medically pickled, the other dissected into about 60 component parts, each frozen by having layers of artificial snow sifted over it.

Later, Ms Bullock will shave the tissue into such microscopically thin strips that on slides it will appear almost transparent.

And always, she is respectful. Researchers must sign a document pledging their dignified use of what she calls a "huge, wonderful gift".