WE ARE OUR BRAINS - CHAPTER 11
REPAIR AND ELECTRIC STIMULATION
MACULAR DEGENERATION
The most common form of age-related blindness. New blood vessels form right under the yellow spot, macula of the retina, where you see your best. That destroys the retina, and you start to lose your sight, starting from the middle of the field of vision: first you see distorted images, and then a black spot in the middle, which becomes larger. Antibodies are injected every month into the eyes to prevent growth of new blood vessels.
DEPTH ELECTRODES
Are used for obesity, reduction of Parkinson's tremors, tinnitus.
HAPPINESS
"Happiness is nothing more than good health and a poor memory."
It doesn't depend on having a goal, in the end life itself just came to be randomly. But enjoying life is more important because it is closely related to eating and reproducing and therefore promotes survival. However, if it is done too much, it can lead to obesity and overpopulation.
Hearing and vision are being improved by electrical implants in the brain. Paralysis may be treated with prosthetics in the future: they will read the intended actions of the brain and then carry them out.
PARKINSON'S DISEASE
Characterised by the death of domaine-producing cells located in the part of the brain called the substrata nigra-black substance, because it shows up black in autopsies due to the dark pigmentation of dopamine-producing neurons. When they die, they can't control the motor area in the middle of the brain: striatum and this leads to movement impairment.
So transplants of brain tissue can help restore the dopamine producing cells. But they are hard to find because you need four embryos for one transplant, and if you just use embryonic stem cells, they can grow into tumours. In two years however, there is no difference between the patients who had and didn't have the transplant.
Even pig brain cells have been transplanted into Parkinson's patients, however most cells died.
HUNTINGTON'S DISEASE
An inherited condition causing movement problems where brain cells in the striatum waste away. Later, dementia ensues. Also treated with foetal brain cell transplant.
GENE THERAPY
Pieces of DNA are inserted into a cell which then produces medicine in the form of a protein. Already used for eye disorders, Alzheimer's. A modified virus acts as a vector: it is able to penetrate the cell, but no longer multiply and cause disease.
ALD
A hereditary condition in which people lack the ALD protein that breaks down fatty acids. These then build up in the myelin sheath that coats nerve fibres, which then lose their function: causing progressive physical and mental disability.