Isolated brain refers to keeping a brain alive in-vitro. This is done either by perfusion by a blood substitute, often an oxygenated solution of various salts, or by submerging the brain in oxygenated artificial cerebrospinal fluid (CSF). It is the biological counterpart of brain in a vat. A related concept, attaching the brain or head to the circulatory system of another organism, is called a head transplant. An isolated brain however is more typically attached to an artificial perfusion device rather than a biological body.
The brains of many different organisms have been kept alive in-vitro for hours, or in some cases days. The central nervous system of invertebrate animals is often easily maintained as they need less oxygen and to a larger extent get their oxygen from CSF, for this reason their brains are more easily maintained without perfusion. Mammalian brains on the other hand have a much lesser degree of survival without perfusion and an artificial blood perfusate is usually used.
For methodological reasons, most research on isolated mammalian brains has been done with guinea pigs. These animals have a significantly larger basilar artery (a major artery of the brain) compared to rats and mice, which makes cannulation (to supply CSF) much easier.
Famous quotes containing the words isolated and/or brain:
“I cant earn my own living. I could never make anything turn into money. Its like making fires. A careful assortment of paper, shavings, faggots and kindling nicely tipped with pitch will never light for me. I have never been present when a cigarette butt, extinct, thrown into a damp and isolated spot, started a conflagration in the California woods.”
—Margaret Anderson (18861973)
“Knowledge of Rome must be physical, sweated into the system, worked up into the brain through the thinning shoe-leather.... When it comes to knowing, the senses are more honest than the intelligence. Nothing is more real than the first wall you lean up against sobbing with exhaustion.”
—Elizabeth Bowen (18991973)