Unexplainable.Net

1989 BrainTheory Proven True

This news article was taken from the Dallas Times Herald, Wednesday,

November 1, 1989. The article originated from the Los Angeles Times.

SCIENTISTS PROVE BRAIN THEORY

(Computer-like `hard-wiring’ allows cells to store memories)

LOS ANGELES – Researchers at the University of Southern

California and the University of Illinois Have for the first time

experimentally confirmed the longstanding theory that the brain stores

memories by “hard-wiring” new connections between groups of brain

cells.

Their results, to be reported today at a meeting of the Society

for Neuroscience in Phoenix, Ariz. are the culmination of decades of

research for the physical mechanisms underlying the mysterious process

by which the brain stores memories.

In two separate sets of experiments involving rats and rabbits,

the researchers clearly identified memory-related changes in the

physical links among groups of brain cells, or neurons. The changes

occurred when the animals learned specific physical activities, such

as blinking an eye in response to the ringing of a bell or learning to

walk along an elevated pathway.

The experiments offer an explanation for why some types of

learned behavior, such as the ability to ride a bicycle, are never

forgotten. The reason is that the necessary muscle commands for

riding a bicycle, for instance, are hard-wired into brain cells in the

same way that some commands for operating a computer are permanently

stored by wiring transistors together.

“In terms of vertebrates, we really haven’t had any direct

information about anatomical changes related to specific learning

events,” said neuroscientist Lawrence R. Squire of the Veterans

Affairs Hospital in San Diego. “This will greatly increase our level

of certainty” about how memories are formed, he added.

Psychobiologists Richard F. Thompson of USC and William Greenough

of Illinois have been studying a so-called Pavlovian response in

rabbits. The technique is named after Russian physiologist Ivan

Pavlov, who rang a bell every time he fed a group of dogs. After

training, the dogs began to salivate evert time the bell was rung,

even if they were not given food.

Thompson rang a bell every time he directed a mild puff of air

into one eye of rabbits, causing them to blink. After training, the

rabbits would blink every time the bell was rung.

Implanting microelectrodes throughout the brain, Thompson and his

colleagues found that the learned blinking was controlled by a small

group of cells, called Purkinje cells, in the cerebellum, which is the

brain’s coordinating center for muscular activity. When they

surgically removed the small group of Purkinje cells, the animals no

longer blinked.

Thompson then turned the trained animals over to Greenough, whose

specialty is looking for signs of increased connections between brain

cells.

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In previous studies with rats, Greenough had shown that rats

raised in an “enriched” environment – one with lots of toys and other

mentally stimulating objects – have a much greater number of

intercellular connections then those raised in a more sterile

environment. In those cases, however, the increased connections could

not be associated with specific memories.

In the new study, Greenough and his students studied the number

of intercellular connections in the specific area of the cerebellum

that Thompson had shown controlled the eye-blink behavior. They

compared the number of connections in this area to the number on the

opposite side of the cerebellum, controlling the eyelid that was not

trained, and found a significant difference.

In the 15 rabbits studied over a two-year period,

“The differences were statistically reliable and clearly visible,”

Greenough said. “We really have isolated a case where, in brain

cells that are clearly involved in the performance of a task, we

have crystal clear [structural] change that indicated a change in

anatomical circuitry.”

The discovery of altered numbers of connections, Thompson added,

“is not surprising, in that it fits theory, but there has been no

particular evidence [to support the theory] before. We were

convinced there would be something like this because memories are

never forgotten.”

The cerebellums of all mammals are remarkably similar, Greenough

noted, and researchers are confident that discoveries made in animal

brains are applicable to humans. They also believe that the mechanism

used for storing memories involved with muscle movements will be

similar, if not identical to, those involved in storing other types of

memories.

Thompson noted that the brain has the potential for “trillions

and trillions” of such physical connections, so that the physical

structure of the brain does not limit the number of things that can be

remembered.

Both Thompson and Greenough caution that researchers are only

beginning to unravel the mechanism of memory formation. “This is a

major advance,” Greenough said, “but it is only a first step that

leads to a lot more research rather then a last step that wraps

everything up.”

{Gee Wiz it’s amazing how medical science is advancing! Just

think that maybe they will discover that magnetic energies can

effect the BRAIN !!! }

R.B.